SA node:
Sinoatrial node. The pacemaker of the heart, located in the
right atrium (upper chamber of the heart). The electrical
signals initiated in the SA node are transmitted throuhg the
atria and the ventricles to stimulate heart muscle
contractions (heartbeats).
Sabin vaccine: Oral Polio virus Vaccine (OPV). The polio virus
in OPV is attenuated (weakened). The Sabin vaccine is named
after the American virologist Albert Sabin. See Immunization,
polio.
Sagittal: A vertical plane passing through the body which
divides it into left and right sides.
Salivary: Glands in the mouth that produce saliva. The salivary
glands can become inflamed in diseases, such as Sjogren's
syndrome and mumps.
Salk vaccine: Inactivated Polio Vaccine (IPV). The polio virus
in IPV has been inactivated (killed). The Salk vaccine is named
after the American physician-virologist Jonas Salk. See
Immunization, polio.
Salpingo-oophorectomy: Removal of the fallopian tubes and
ovaries.
Sapphism: Female homosexuality. Named after the poet Sappho who
lived on the Greek island of Lesbos (circa 600 BC). She was a
lesbian by geography and sexual orientation. Also called
lesbianism.
Sarcoma: A type of cancer that starts in bone or connective
tissue.
Satellite DNA: DNA that contains many tandem (not inverted)
repeats of a short basic repeating unit. Satellite DNA is
located at very specific spots in the genome (on chromosomes 1,
9, 16 and the Y chromosome, the tiny short arms of chromosomes
13-15 and 21 and 22, and near the centromeres of chromosomes).
Scalded skin syndrome: A potentially serious side effect of
infection with the Staph (Staphylococcus) bacteria that produces
a specific protein which loosens the "cement" holding the
various layers of the skin together. This allows blister
formation and sloughing of the top layer of skin. If it occurs
over large body regions it can be deadly (just like a large
surface area of the body having been burned). It is necessary to
treat scalded skin syndrome with intravenous antibiotics and to
protect the skin from allowing dehydration to occur if large
areas peel off. The disease occurs predominantly in children
under 5 years of age. It is known formally as Staphyloccoccal
scalded skin syndrome and as Ritter disease.
Schistosoma haematobium: A species of trematode worm that
parasitizes humans and causes urinary tract disease. See
Schistosomiasis.
Schistosoma japonicum: A species of trematode worm that
parasitizes humans and that (like S. mansoni) causes liver and
gastrointestinal tract disease. See Schistosomiasis.
Schistosoma mansoni: A species of trematode worm that
parasitizes humans and that (like S. japonicum) causes liver and
gastrointestinal tract disease. See Schistosomiasis.
Schistosomiasis: Disease of liver, gastrointestinal tract and
bladder caused by trematode worms that parasitize people. The
infection is acquired from infested water. Three main species of
these trematode worms (flukes)--Schistosoma haematobium, S.
japonicum, and S. mansoni—cause disease in humans. Larval forms
of the parasite live in freshwater snails. The cercaria (form of
the parasite) is liberated from the snail burrow into skin,
transforms to the schistosomulum stage, and migrates to the
urinary tract (S. haematobium), liver or intestine (S. japonicum,
S.mansoni) where the adult worms develop. Eggs are shed into the
urinary tract or the intestine and hatch to form miracidia (yet
another form of the parasite) which then infect snails,
completing the life cycle of the parasite. Adult schistosome
worms can seriously damage tissue. Schistosome species which
cannot live in man cause swimmer’s itch. Schistosomiasis is also
called bilharzia after the shortlived German physician Theodor
Bilharz (1825-1862)
Schizophrenia: The most common form of psychosis, characterized
by partial or total withdrawal of interest in the world outside
of oneself and loss of intellectual and emotional function.
Sciatica: Pain resulting from irritation of the sciatic nerve,
typically felt at the back of the thigh. The sciatic nerve is
the largest nerve in the body and begins from nerve roots in the
lumbar spinal cord in the low back and extends through the
buttock area to send nerve endings down the lower limbs. While
sciatica is most commonly a result of a disc herniation directly
pressing on the nerve, any cause of irritation or inflammation
of this nerve can reproduce the symptoms of sciatica.
Sclerencephaly: A general term for scarring and shrinkage of the
substance of the brain. Sclerencephaly occurs because of chronic
inflammation of the brain matter.
Sclerosis, multiple (MS): The National Multiple Sclerosis
Society says of MS that it is "a disease that randomly attacks
your central nervous system, wearing away the control you have
over your body. Symptoms may range from numbness to paralysis
and blindness. The progress, severity and specific symptoms
cannot be foreseen. You never know when attacks will occur, how
long they will last, or how severe they will be. Most people are
diagnosed with MS between the ages of 20 and 40...." In medical
terms, MS involves demyelinization of the white matter sometimes
extending into the gray matter. Demyelinization is loss of
myelin, the coating of nerve fibers composed of lipids (fats)
and protein that serves as insulation and permits efficient
nerve fiber conduction. The "white matter" is the part of the
brain which contains myelinated nerve fibers and appears white,
whereas the gray matter is the cortex of the brain which
contains nerve cell bodies and appears gray. When myelin is
damaged in MS, nerve fiber conduction is faulty or absent.
Impaired bodily functions or altered sensations associated with
those demyelinated nerve fibers give rise to the symptoms of MS.
Recent research (1998) has also identified nerve cell death as
part of the nervous system injury in MS.
Scoliosis: Sideways (lateral) curvature of the spine. Scoliosis
is usually an incidental and harmless finding. When severe,
scoliosis can be improved by surgical correction.
Score, Apgar: A practical method to assess a newborn infant, the
Apgar score is a number arrived at by scoring the heart rate,
respiratory effort, muscle tone, skin color, and response to a
catheter in the nostril. Each of these objective signs can
receive 0, 1, or 2 points. An Apgar score of 10 means an infant
is in the best possible condition.. The Apgar score is done
routinely 60 seconds after the complete birth of the infant. An
infant with a score of 0-3 needs immediate resusitation. The
Apgar score is commonly repeated 5 minutes after birth and in
the event of a difficult resusitation, the Apgar may be done
again at 10, 15, and 20 minutes. An Apgar score of 0-3 at 20
minutes of age is predictive of high morbidity (disease) and
mortality. The score is named for the American anesthesiologist
Virginia Apgar (1909-1974) at Columbia University in New York
who originated the scoring method.
Scrape: Abrasion. Washing a cut or scrape with soap and water
and keeping it clean and dry is all that is required to care for
most wounds. Putting alcohol, hydrogen peroxide, and iodine into
a wound can delay healing and should be avoided. Seek medical
care early if you think that you might need stitches. Any delay
can increase the rate of wound infection. Any puncture wound
through tennis shoes has a high risk of infection and should be
seen by your healthcare professional. Any redness, swelling,
increased pain, or pus draining from the wound may indicate an
infection that requires professional care.
Scrotum: A pouch of skin which contains the testes, epididymides,
and lower portions of the spermatic cords.
Scrub typhus: A mite-borne infectious disease caused by a
microorganism, Rickettsia tsutsugamushi, characteristically with
fever, headache, a raised (macular) rash, swollen glands (lymphadenopathy)
and a dark crusted ulcer (called an eschar or tache noire) at
the site of the chigger (mite larva) bite. This disease occurs
in the area bounded by Japan, India, and Australia. Known also
as Tsutsugamushi disease, mite-borne typhus, and tropical
typhus.
Sebaceous cyst: A sebaceous cyst is a rounded swollen area of
the skin formed by an abnormal sac of retained excretion (sebum)
from the sebaceous follicles.
Sebaceous gland: A normal gland of the skin which empties an
oily secretion into the hair follicle near the surface of the
skin.
Seborrhea: A accumulation of scales of greasy skin, often on the
scalp. Dandruff.
Seborrheic keratosis: A benign skin lesion resulting from
excessive growth of the top layer of skin cells. It usually is
found in persons over 30 years old and may be few or numerous.
Sebum: An oily secretion of the sebaceous gland which helps to
preserve the flexibility of the hair.
Secretin: Hormone made by glands in the small intestine that
stimulates pancreatic secretion. The word "hormone" was coined
by the English physiologists Wm. M. Bayliss and Ernest H.
Starling in connection with their discovery of secretin, the
first hormone, in 1902.
Section (anatomic): A slice of tissue. A biopsy obtained by
surgery is usually sectionned (sliced). And all the "sections"
under the microscope might, for example, reveal entirely benign
cells with no hint of cancer.
Section (obstetrical): Short for a Caesarian section. In
surgery, the word "section" refers to the division of tissue.
Here, the division of tissue involves the abdominal wall of the
mother and the wall of the uterus which are "sectionned" in
order to deliver the baby from the uterus (womb).
Section, Caesarian: Procedure in which an infant, rather than
being born vaginally, is surgically removed from the uterus. As
the name "Caesarian" suggests, this is not a new procedure. it
was done in ancient civilizations upon the death of a pregnant
woman near term to salvage the baby. Julius Caesar (or, more
likely, one of his predecessors) was born by this procedure. The
term "section" in surgery refers to the division of tissue. What
is being divided here is the abdominal wall of the mother and
the wall of the uterus in order to extract the baby. In
Shakespeare’s "Macbeth" the Witches’ prophecy was that "...none
of woman born/ Shall harm Macbeth" (IV.i). Unfortunately for
Macbeth, the Scottish nobleman Macduff was "from his mother’s
womb/ Untimely ripped." and thus not naturally "born of
woman"(V.vii). Macduff is the only agent capable of destroying
Macbeth. He kills Macbeth in battle.
Section, cross: A transverse cut through a structure. The
opposite is a longitudinal section.
Section, longitudinal: A cut along the long axis of a structure
Sedimentation rate: A sedimentation rate, or "sed rate", is a
blood test that detects and monitors inflammation activity. It
is measured by recording the rate at which red blood cells (RBCs)
sediment in a tube over time. It increases (the RBCs sediment
faster) with more inflammation.
Segawa’s dystonia: An important variant of dopa-responsive
dystonia (DRD). Typically, DRD begins in childhood or
adolescence with progressive difficulty in walking and, in some
cases, spasticity. In Segawa’s dystonia, the symptoms fluctuate
during the day from relative mobility in the morning to
increasingly worse disability in the afternoon and evening as
well as after exercise.
Seizure: A seizure is a sudden attack of epileptic convulsion.
It is a result of involuntary electrical activity in the brain.
It can be associated with uncontrolled motor (movement) or
sensory system action. Accordingly, a patient suffering a
seizure may experience uncontrollable body movements, unusual
smells or tastes and have loss of consciousness (awareness of
surroundings).
Seizure, causes of: Known causes of seizures include head
injuries, brain tumors, lead poisoning, maldevelopment of the
brain, genetic and infectious illnesses. But in fully half of
the patients with seizures, no cause can be found.
Selective Estrogen-Receptor Modulator (SERM): A "designer
estrogen" which possesses some, but not all, of the actions of
estrogen. For example, raloxifene (trade name EVISTA) is
classified as a SERM because it prevents bone loss (like
estrogen) and lowers serum cholesterol (like estrogen) but
(unlike estrogen) does not stimulate the endometrial lining of
the uterus.
Selenium: An essential mineral that is a component of a key
antioxidant enzyme, glutathione reductase, in tissue
respiration. Deficiency of selenium causes Keshan disease, a
fatal form of cardiomyopathy (disease of the heart muscle) first
observed in Keshan province in China and since found elsewhere.
According to the National Academy of Sciences, the Recommended
Dietary Allowances of selenium are 70 milligrams per day for men
and 55 milligrams per day for women. Food sources of selenium
include seafoods, some meats such as kidney and liver, and some
grains and seeds. Too much selenium may cause reversible changes
in the hair (balding) and nails, garlic odor to the breath,
intestinal distress, weakness and slower mentation (slowed
mental functioning).
Selenium deficiency: Deficiency of the essential mineral
selenium causes Keshan disease, a fatal form of cardiomyopathy
(disease of the heart muscle) first observed in Keshan province
in China and since found elsewhere. According to the National
Academy of Sciences, the Recommended Dietary Allowances of
selenium are 70 milligrams per day for men and 55 milligrams per
day for women. Food sources of selenium include seafoods, some
meats such as kidney and liver, and some grains and seeds
Selenium excess: Too much of the mineral selenium may cause
reversible changes in the hair (balding) and nails, garlic odor
to the breath, intestinal distress, weakness and slower
mentation (slowed mental functionning). According to the
National Academy of Sciences, the Recommended Dietary Allowances
of selenium are 70 milligrams per day for men and 55 milligrams
per day for women.
Seminal vesicles: Two structures about 5 cm long behind the
bladder and above the prostate gland which contribute fluid to
the ejaculate.
Septal defect, atrial (ASD): A hole in the septum, the wall,
between the atria, the upper chambers of the heart. Commonly
called an ASD. ASDs are a major class of heart deformity that is
present at birth (congenital cardiac malformation).
Septal defect, ventricular (VSD): A hole in the interventricular
septum, the wall between the ventricles, the lower chambers of
the heart. Commonly called a VSD. VSDs are a common class of
heart deformity that is present at birth (congenital cardiac
malformation)..
Septate: Divided: A septate uterus is a one that is divided.
Septate vagina: A vagina that is divided, usually
longitudinally, to create a double vagina. This situation can be
easily missed by the patient and even by the doctor on exam. If
the patient becomes sexually active prior to diagnosis, one of
the vaginas stretches and becomes "dominant". The other vagina
slips slightly upward and flush and is a little difficult to
enter.
Septic bursitis: A bursa is a closed fluid-filled sac that
functions as a gliding surface to reduce friction between
tissues of the body. When the bursa becomes inflamed, the
condition is known as "bursitis." When the bursa is infected
with bacteria, the condition is called septic bursitis.
Septum: A word borrowed from the Latin "saeptum" meaning a
"dividing wall or enclosure."
Septum, interatrial: The wall separating the upper chambers (the
atria) of the heart. A hole in the interatrial septum is termed
an atrial septal defect (ASD).
Septum, interventricular: The wall separating the lower chambers
(the ventricles) of the heart. A hole in the interventricular
septum is termed a venticular septal defect (VSD).
Septum, nasal: The dividing wall that runs down the middle of
the nose so that there are normally two sides to the nose, each
ending in a nostril.
Sequence, complementary: Nucleic acid sequence of bases that can
form a double- stranded structure by matching base pairs. For
example, the complementary sequence to C-A-T-G (where each
letter stands for one of the bases in DNA) is G-T-A-C.
Sequence, conserved: A base sequence in a DNA molecule (or an
amino acid sequence in a protein) that has remained essentially
unchanged throughout evolution.
Sequence, regulatory: A sequence of bases in DNA that controls
the expression of a gene.
Sequence tagged site (STS): A short (200 to 500 base pairs) DNA
sequence that occurs but once in the human genome and whose
location and base sequence are known. Detectable by polymerase
chain reaction, STSs are useful for localizing and orienting the
mapping and sequence data reported from many different
laboratories and serve as landmarks on the developing physical
map of the human genome. Expressed sequence tags (ESTs) are STSs
derived from comlementarty DNAs (cDNAs).
Sequencing: Learning the order of nucleotides (base sequences)
in a DNA or RNA molecule or the order of amino acids in a
protein.
SERM: Selective Estrogen-Receptor Modulator.
Serositis: Inflammation of the serous tissues of the body. The
serous tissues line the lungs (pleura), heart (pericardium), and
the inner lining of the abdomen (peritoneum) and organs within.
Serotonin: A chemical in the brain involved in the transmission
of nerve impulses. Serotonin.can trigger the release of
substances in the blood vessels of the brain that in turn cause
the pain of the migraine.
Serum: The clear liquid that separates from clotted blood. Serum
differs from plasma, the liquid that separates from unclotted
blood. "Serum" is the Latin word for "whey", the watery liquid
that separates from the curds in > cheesemaking.
Serum hepatitis: An obsolete term. See Hepatitis B.
Sexually transmitted disease (STD): Any disease transmitted by
sexual contact. Examples: gonorrhea, syphilis, AIDS.. The older
term was venereal disease.
Sexually transmitted diseases in women: Gonorrhea and chlamydia
are bacterial sexually transmitted diseases (STDs) frequently
found together. Gonorrhea is NOT transmitted from toilet seats.
Women infected with it may not have any symptoms but can end up
later with severe pelvic infection. Early syphilis causes a
mouth or genital ulcer (chancre) and later can cause hair loss,
headaches, sore throat, and skin rash. Even later, syphilis can
lead to heart and brain damage. Genital herpes is a viral
infection that can cause painful genital sores. Genital warts
are caused by viruses and can increase a woman’s risk for cancer
of the cervix. AIDS is caused by the human immunodeficiency
virus (HIV). Hepatitis B is a virus that causes liver
inflammation and can lead to cirrhosis and cancer of the liver.
Hepatitis B can now be prevented with a vaccine. There is no
"safe" sex. Condoms do not necessarily prevent STDs.
Shell shock: The World War I name for what is known today as
post-traumatic stress, this is a psychological disorder that
develops in some individuals who have had major traumatic
experiences (and, for example, have been in a serious accident
or through a war). The person is typically numb at first but
later has symptoms including depression, excessive irritability,
guilt (for having survived while others died), recurrent
nightmares, flashbacks to the traumatic scene, and overreactions
to sudden noises. Post-traumatic stress became known as such in
the 70s due to the adjustment problems of some Vietnam veterans.
Shin bone fever: A louse-borne disease first recognized in the
trenches of World War I, again a major problem in the military
in World War II, seen endemically in Mexico, N. Africa, E,
Europe, and elsewhere. The cause, Rochalimaea quintana, is an
unusual rickettsia that multiplies in the gut of the body louse.
Transmission to people can occur by rubbing infected louse feces
into abraded (scuffed) skin or conjunctiva (whites of the eyes).
Onset of symptoms is sudden, with high fever, headache, back and
leg pain and a fleeting rash. Recovery takes a month or more.
Relapses are common. Also called trench fever, Wolhynia fever,
quintan fever, five-day fever, Meuse fever, His’ disease,
His-Werner disease, Werner-His disease.
Shingles: Shingles is an acute infection by a virus called
Herpes zoster, which causes an eruption of vesicles in the skin.
The eruption is usually distributed along the area of the skin
that is innervated by a nerve that supplies sensation. The pain
associated with shingles is, in part, related to inflammation of
the associated sensory nerve.
Shock: In medicine, shock is a critical condition brought on by
a sudden drop in blood flow through the body. There is failure
of the circulatory system to maintain adequate blood flow. This
sharply curtails the delivery of oxygen and nutrients to vital
organs. It also compromises the kidney and so curtails the
removal of wastes from the body. Shock can be due to a number of
different mechanisms including not enough blood volume (hypovolemic
shock) and not enough output of blood by the heart (cardiogenic
shock). The signs and symptoms of shock include low blood
pressure (hypotension), overbreathing (hyperventilation), a weak
rapid pulse, cold clammy grayish-bluish (cyanotic) skin,
decreased urine flow (oliguria), and mental changes (a sense of
great anxiety and forboding, confusion and, sometimes,
combativeness). Shock is a major medical emergency.
Shock, cardiogenic: Shock caused by heart failure. The heart
fails to pump blood effectively. For example, a heart attack (a
myocardial infarction) can cause an abnormal ineffectual heart
beat (an arhythmia) with very slow, rapid, or irregular
contractions of the heart, impairing the heart’s ability to pump
blood, lowering the volume of blood going to vital organs.
Cardiogenic shock can also be due to drugs that reduce heart
function or an abnormally low level oxygen in the blood
(hypoxemia) caused, for instance, by lung disease. Whatever be
the cause, blood vessels constrict and adrenalin-like substances
are secreted into the bloodstream, increasing the heart rate.
Treatment of cardiogenic shock is aimed at improving the heart’s
function. Shock after a heat attack is extremely serious. The
mortality rate is over 80%.
Shock, hypovolemic: Shock due to a decrease in blood volume.
This is the #1 cause of shock. It can be due to loss of blood
from bleeding, loss of blood plasma through severe burns, and
dehydration. The treatment, first and foremost, is prompt
intravenous administration of fluid.
Shock, psychologic: Trauma due to psychological events, as in
"shell shock" (now known as post-traumatic stress disorder).
Shock, shell: The World War I name for what is known today as
post-traumatic stress, this is a psychological disorder that
develops in some individuals who have had major traumatic
experiences (and, for example, have been in a serious accident
or through a war). The person is typically numb at first but
later has symptoms including depression, excessive irritability,
guilt (for having survived while others died), recurrent
nightmares, flashbacks to the traumatic scene, and overreactions
to sudden noises. Post-traumatic stress became known as such in
the 70s due to the adjustment problems of some Vietnam
veterans.Shots, allergy: Known medically as allergy
desensitization or allergy immunotherapy, the injections are
designed to stimulate the immune system with gradually
increasing doses of the substances to which a person is
allergic, the aim being to modify or stop the allergy "war" (by
reducing the strength of the IgE and its effect on the mast
cells). This form of treatment is very effective for allergies
to pollen, mites, cats, and especially stinging insects (eg,
bees, hornets, yellowjackets, wasps, velvet ants, fire ants).
Allergy immunotherapy usually takes 6 months to a year to become
effective and injections are usually required for 3-5 years.
Shock, toxic: See Syndrome, toxic shock.
Shots, allergy: Known medically as allergy desensitization or
allergy immunotherapy, the injections are designed to stimulate
the immune system with gradually increasing doses of the
substances to which a person is allergic, the aim being to
modify or stop the allergy "war" (by reducing its effect on the
mast cells). This form ofhe strength of the IgE and its
treatment is very effective for allergies to pollen, mites,
cats, and especially stinging insects (eg, bees, hornets,
yellowjackets, wasps, velvet ants, fire ants). Allergy
immunotherapy usually takes 6 months to a year to become
effective and injections are usually required for 3-5 years.
Shoulder bursitis: A bursa is a fluid-filled sac that functions
as a gliding surface to reduce friction between moving tissues
of the body. There are two major bursae of the shoulder.
Bursitis is usually not infectious, but the bursa can become
infected. Treatment of non-infectious bursitis includes rest,
ice, and medications for inflammation and pain. Infectious
bursitis is treated with antibiotics, aspiration, and surgery.
Show: An appearance.
Show, bloody: Literally, the appearance of blood. The bloody
show consists of blood-tinged mucus created by extrusion and
passage of the mucous plug that filled the cervical canal (the
canal between the vagina and uterus) during pregnancy. The
bloody show is a classic sign of impending labor. The same term,
bloody show, can be applied to the beginning of menstruation.
Shprintzen syndrome: Congenital malformation (birth defect)
syndrome with cleft palate, heart defect, abnormal face, and
learning problems. The condition is also called the velo-cardio-facial
(VCF) syndrome. (The velum is the soft palate). Other less
frequent features include short stature, small-than-normal head
(microcephaly), mental retardation, minor ear anomalies, slender
hands and digits, and inguinal hernia. The cause is usually a
microdeletion in chromosome band 22q11.2, just as in DiGeorge
syndrome. Shprintzen and DiGeorge syndromes are different
clinical expressions of essentially the same chromosome defect.
Shulman’s syndrome (Eosinophilic fasciitis): A disease which
leads to inflammation and thickening of the skin and fascia.
(The fascia is a lining tissue under the skin that covers a
surface of underlying tissues. When the fascia is inflamed, the
condition is referred to as "fasciitis.") In eosinophilic
fasciitis, the involved fascia is inflamed with the eosinophil
white blood cells. There is progressive thickening, and often
redness and warmth, and hardness of the skin surface.
Shunt: A catheter (tube) that carries cerebrospinal fluid from a
ventricle in the brain to another area of the body.
Side effects: Problems that occur when treatment affects healthy
cells. Common side effects of cancer treatment are fatigue,
nausea, vomiting, decreased blood cell counts, hair loss, and
mouth sores.
SIDS (Sudden Infant Death Syndrome): The sudden and unexpected
death of a baby with no known illness, typically affecting
infants from 2 weeks to 6 months of age while sleeping. At
elevated risk for SIDS are children with a brother or sister who
died of SIDS; babies whose mothers smoked or used heroin,
methadone, or cocaine during pregnancy; infants born weighing
less than 4.4 pounds (2000 grams); children with an abnormal
breathing pattern with long periods without taking a breath
(apnea); and babies who sleep on their stomachs. Since babies
who sleep on their stomachs are at least 3 times more likely to
die of SIDS than babies who sleep on their backs, children’s
health authorities such as the American Academy of Pediatrics
recommend always placing infants on their backs to sleep.
Sigmoidoscope: A lighted instrument used to view the inside of
the lower colon.
Sigmoidoscopy: Sigmoidoscopy is a procedure whereby a doctor
inserts a viewing tube (sigmoidoscope) into the rectum for the
purpose of inspecting the lower colon (sigmoid colon) and
rectum. If an abnormal area is detected, a biopsy can be
performed.
Sign: Any abnormality, such as a change in appearance,
sensation, or function, observed by a physician when evaluating
a patient which indicates a disease process.
Single-gene diseases: Hereditary disorders caused by a change
(mutation) in a single gene. There are thousands of single-gene
diseases including achondroplastic dwarfism, Huntington disease,
cystic fibrosis, sickle cell disease, Duchenne muscular
dystrophy, and hemophilia. Single-gene diseases typically
describe classic simple Mendelian patterns of inheritance (as
autosomal dominant, autosomal recessive, and X-linked traits) by
comparison with polygenic diseases.
Sino-atrial node: See SA node.
Sinus tachycardia: Fast heartbeat (tachycardia) occurring
because of rapid firing by the SA node, the natural pacemaker of
the heart. Electrical signals initiated in the SA node are
transmitted to the atria and the ventricles to stimulate heart
muscle contractions heartbeats. Sinus tachycardia is usually a
rapid contraction of a normal heart in response to a condition,
drug, or disease as, for examples, pain, fever, excessive
thyroid hormone, exertion, excitement, low blood oxygen level
(hypoxia), or stimulant drugs such as caffeine, cocaine, and
amphetamines. However, in some cases, it can be a sign of heart
failure, heart valve disease, or other illness.
Sinusitis: Sinusitis is inflammation of the lining membrane of
any of the hollow areas (sinuses) of the bone of the skull
around the nose. The sinuses are directly connected to the nasal
cavities.
Situs inversus totalis: A condition in which there is complete
transposition (right to left reversal) of the thoracic and
abdominal organs. The heart is not in its usual position in the
left chest but is on the right. Specifically related to the
heart, this is referred to as dextrocardia (literally,
right-hearted). And the stomach, which is normally in the left
upper abdomen, is on the right. In patients with situs inversus
totalis, all of the chest and abdominal organs are reversed and
appear in mirror image when examined or visualized by tests such
as x-ray filming. Situs inversus totalis has been estimated to
occur once in about 6-8,000 births. Situs inversus occurs in a
rare abnormal condition that is present at birth (congenital)
called Kartagener’s syndrome.
Sixth disease: A viral disease of infants and young children
with sudden onset of high fever which lasts several days and
then suddenly subsides leaving in its wake a fine red rash. The
causative agent is herpesvirus type 6 so the disease is known as
Sixth Disease. Also known as Exanthem subitum (sudden rash),
Pseudorubella, Roseola, Roseola infantilis, and Roseola infantum.
Skeletal dysplasia: One of a large contingent of genetic
diseases in which the bony skeleton is abnormally formed during
development. For example, achondroplasia (achondroplastic
dwarfism).
Skeletal muscle: One of three types of muscle tissue in the body
(skeletal, smooth, cardiac) which represents the majority of the
muscular tissue in the body. Skeletal muscle is the type of
muscle which powers movement of the skeleton as in walking and
lifting.
Skeleton: The skeleton is composed of bones and is the framework
of the body.
Skin graft: Skin that is moved from one part of the body to
another.
Skin, scalded, syndrome: See Scalded skin syndrome.
Skin test for allergy: Test done on the skin to identify the
allergy substance (allergen) triggering the allergic reaction. A
small amount of the suspected allergy substance is placed on the
skin. The skin is then gently scratched through the small drop
with a special sterile needle. If the skin reddens and, more
importantly, swells, then allergy to that substance is probable.
Skull: The skull is a collection of bones which encases the
brain and gives form to the head and face. These bones include
the following - frontal, parietal, occipital, temporal,
sphenoid, ethmoid, zygomatic, maxilla, nasal, vomer, palatine,
inferior concha, and mandible.
Slanted ear: An ear that is slanted more than usual.
Technically, an ear is slanted when the angle of the slope of
the auricle is more than 15 degrees from the perpendicular.
Considered a minor anomaly. The presence of 2 or more minor
anomalies in a child increases the probability that the child
has a major malformation.
Sleep apnea: Temporary stoppage of breathing during sleep, often
resulting in daytime sleepiness.
Small cell lung cancer: A type of lung cancer in which the cells
are small and round. Also called oat cell lung cancer.
Small intestine: The part of the digestive tract that extends
from the stomach to the large intestine.
Smoldering leukemia: A condition in which the bone marrow does
not function normally. It does not produce enough blood cells.
This condition may progress and become acute leukemia.
Smoldering leukemia also is called myelodysplastic syndrome or
preleukemia.
Smooth muscle: One of the three types of muscle tissue in the
body (skeletal, smooth, cardiac). Generally forms the supporting
tissue of blood vessels and hollow internal organs such as the
stomach, intestine, and bladder. So named because of the absence
of microscopic lines called "cross-striations" which are seen in
the other two types.
Snoring: During normal breathing, air passes through the throat
en route to the lungs and travels by the tongue, soft palate
(the back of the roof of the mouth), uvula (the prominent
anatomic structure dangling downward visibly at the back of the
mouth), and tonsils. When a person is awake, the muscles in the
back of the throat tighten to hold these structures in place and
prevent them from collapsing and vibrating in the airway. During
sleep, the uvula and soft palate frequently vibrate causing the
sounds of snoring.
Soft palate: The muscular part of the roof of the mouth. The
soft palate is directly behind the hard palate. It lacks bone
and so is soft.
Soft tissue sarcoma: A sarcoma that begins in the muscle, fat,
fibrous tissue, blood vessels, or other supporting tissue of the
body. Not a type of bone cancer.
Somnoplasty: A surgical treatment for snoring. Somnoplasty uses
heat energy to remove tissues of the uvula and soft palate.
(See: Snoring). Somnoplasty is usually done as an office
procedure with local anesthesia. It is not indicated for the
treatment of sleep apnea.
Spasmodic dysphonia: Involves the muscles of the throat that
control speech. Also called spastic dysphonia or laryngeal
dystonia, it causes strained and difficult speaking or breathy
and effortful speech.
Spastic colitis: See Syndrome, irritable bowel.
Spastic pseuodoparalysis: Better known as Creutzfeldt-Jakob
disease (CJD). A dementing disease of the brain. It is believed
due to an unconventional (not a bacteria or virus),
transmissible agent called a prion. Symptoms of CJD include
forgetfulness, nervousness, jerky trembling hand movements,
unsteady gait, muscle spasms, chronic dementia, balance
disorder, and loss of facial expression. CJD is classified as a
spongiform encephalopathy. Most cases occur randomly
(sporadically), but inherited forms exist. There is neither
treatment nor cure for CJD. Other names for CJD include
Creutzfeldt-Jakob syndrome and Jakob-Creutzfeldt disease.
Speculum: An instrument used to widen the opening of the vagina
so that the cervix is more easily visible.
Speech pathologist: A specialist who evaluates and treats people
with communication and swallowing problems. Also called a speech
therapist.
Sperm: A sperm is the male "gamete" or sex cell. It combines
with the female "gamete," called an ovum, to form a zygote. The
formation process is called "fertilization." (see ovum, zygote).
Spermatic cord: A group of structures which go through the
inguinal canal to the testis. The structures include the vas
deferens, arteries, veins, lymphatic vessels, and nerves.
Spina bifida: A bony defect in the vertebral column through
which the meningeal membrane and spinal cord may protrude (spina
bifida cystica) or may not protrude so that the defect remains
hidden, covered by skin (spina bifida occulta). Spina bifida
cystica, also known as meningomyelocele (MM), is due to failure
of closure during embryonic life of bottom end of the neural
tube, the structure which gives rise to the central nervous
system (the brain and spinal cord). The term spina bifida refers
specifically only to the bony defect in the vertebral column
but, through usage, the term spina bifida is gradually becoming
synonymous with MM. The risk of spina bifida (and all neural
tube defects) can be decreased by the mother eating ample folic
acid during pregnancy.
Spina bifida cystica: A bony defect in the vertebral column
through which the meningeal membranes that cover the spinal cord
and part of the spinal cord protrude. An alternative term is
meningomyelocele.
Spina bifida occulta: Literally, a hidden cleft in the spine. A
bony defect in the vertebral column which remains hidden,
covered by skin
Spine: Commonly, a reference to the bony building blocks of bone
(vertebral column) surrounding and protecting the spinal cord.
The spine can be categorized according to level of the body,
i.e., cervical spine (neck), thoracic spine (upper and
mid-back), and lumbar spine (low back). A spine also refers to a
short prominence of bone. It is the spines of the vertebrae that
we can feel protruding at the base of the back of our neck and
in the middle of our backs. These spines protect our spinal cord
from injury from behind.
Spirochete: A microscopic bacterial organism, a spirochete
apperars worm-like, spiral-shaped, and wiggles vigorously when
viewed under a microscope. Treponema pallidum, the cause of
syphilis, is a particularly well-known member of the Spirochaeta
family. The term spirochete is an odd hybrid of Greek and Latin
roots, the Latin "spira" for "coil" and the Greek "chaite" for
"long flowing hair," formed because the spirochete looked like a
coil of hair.
Spleen: The spleen is a blood vessel filled organ located in the
upper left abdominal cavity. It is a storage organ for red blood
cells and contains many specialized white blood cells called
"macrophages" which act to filter blood.
Spleen, ruptured: Rupture of the capsule of the spleen, an organ
in the upper left part of the abdomen, is a potential
catastrophe that requires immediate medical and surgical
attention. Splenic rupture permits large amounts of blood to
leak into the abdominal cavity which is severely painful.and
life-threatening. Shock and, ultimately, death can result.
Patients typically require an urgent operation. Rupture of a
normal spleen can be caused by trauma, for example, in an
accident. If an individual’s spleen is enlarged, as is frequent
in mononucleosis, most physicians will not allow activities
(such as major contact sports) where injury to the abdomen could
be catastrophic.
Splenectomy: An operation to remove the spleen.
Splenic fever: Known also as anthrax, splenic fever is a serious
bacterial infection. It is not primarily a human disease but
rather an infection of animals. Cattle, sheep, horses, mules,
and some wild animals are highly susceptible. Humans (and swine)
are generally resistant to anthrax. Anthrax can take different
forms. With the lung form of the disease. People inhale the
anthrax spores and, if untreated, are likely to die. An
intestinal form is caused by eating meat contaminated with
anthrax. But most human anthrax comes from skin contact with
animal products. Cutaneous (skin) anthrax was once well known
among people who handled infected animals, like farmers, >
woolsorters, tanners, brushmakers and carpetmakers in the days
when the brushes and carpets were animal products. The hallmark
of skin anthrax is a carbuncle, a cluster of boils, that
ulcerates in an ugly way. Typically, this lesion has a hard
black center surrounded by bright red inflammation. This
accounts for its name, "anthrax", the Greek word for "coal."
Spondylolisthesis: Forward movement of one building block of the
spine (vertebra) in relation to an adjacent vertebra.
Spotted fever: Rocky Mountain spotted fever (RMSF):, an acute
febrile (feverish) disease initially recognized in the Rocky
Mountain states, caused by Rickettsia rickettsii transmitted by
hard-shelled (ixodid) ticks. Occurs only in the Western
Hemisphere. Anyone frequenting tick-infested areas is at risk
for RMSF. Onset of symptoms is abrupt with headache, high fever,
chills, muscle pain. and then a rash. The rickettsiae grow
within damaged cells lining blood vessels which may become
blocked by clots. Blood vessel inflammation (vasculitis) is
widespread Early recognition of RMSF and prompt antibiotic
treatment is important in reducing mortality. Also called tick
fever, and tick typhus.
Sprue, nontropical: This condition results from an immune
(allergic) reaction to gluten, a protein found in wheat and
related grains and present in many foods that we eat. Sprue
causes impaired absorption and digestion of nutrients through
the small intestine. Symptoms include requent diarrhea and
weight loss. A skin condition called dermatitis herpetiformis
can be associated with celiac sprue. The most accurate
diagnostic test for sprue is a biopsy of the involved small
bowel. Treatment is to avoid gluten in the diet. Medications are
used for refractory (stubborn) sprue. Known under a number of
other names, including celiac sprue.
Spurs, heel: Pointed bony outgrowths at the back of the heel or
under the heel beneath the sole of the foot. Heel spurs at the
back of the heel are associated with inflammation of the
Achilles tendon (tendinitis) and cause tenderness and pain at
the back of the heel made worse while pushing off the ball of
the foot.
Sputum: Mucus from the lungs.
Squamous cells: Flat cells that look like fish scales; they make
up most of the epidermis, the outer layer of the skin.
Squamous cell carcinoma: Cancer that begins in squamous cells,
which are thin, flat cells resembling fish scales. Squamous
cells are found in the tissue that forms the surface of the
skin, the lining of the hollow organs of the body, and the
passages of the respiratory and digestive tracts.
Squamous intraepithelial lesion: A general term for the abnormal
growth of squamous cells on the surface of the cervix. The
changes in the cells are described as low grade or high grade,
depending on how much of the cervix is affected and how abnormal
the cells are. Also called SIL.
Stage: The extent of a cancer, especially whether the disease
has spread from the original site to other parts of the body.
Staging: Doing exams and tests to learn the extent of a cancer,
especially whether it has spread from its original site to other
parts of the body.
STD: Sexually transmitted disease.
STDs in women: See Sexually transmitted diseases in women.
Staph: Very commonly used shortened form of Staphylococcus, a
very common and important group of bacteria. See Staphylococcus.
Staphyloccoccal scalded skin syndrome: See Scalded skin
syndrome.
Staphylococcus: A group of bacteria, familiarly known as Staph,
that can > (and do) cause a multitude of diseases. The name
comes from the Greek staphyle meaning a bunch of grapes + kokkos
meaning berry, and that is exactly what Staph look like under
the microscope, like a bunch of grape or little round berries.
(In technical terms, these are gram-positive, facultative
anaerobic, usually unencapsulated cocci). Staph can cause
illness directly by infection or indirectly through products
they make such as toxins responsible for food poisoning and
toxic shock syndrome.
STAT: A common medical abbreviation which is used to imply
urgent or rush. It is derived from a latin word "statim" which
means immediately.
Stein-Leventhal syndrome: Known descriptively as polycystic
ovarian disease (PCO), this syndrome is basically an hormonal
problem that causes women to have a variety of symptoms
including irregular or no periods, acne, obesity and excessive
hair growth. Women with PCO are at a higher risk for uterine
cancer (endometrial cancer), diabetes, high blood pressure, and
heart disease. With proper treatment, risks can be minimized.
The syndrome is named after the late American gynecologists
Irving F. Stein, Sr. and Michael Leo Leventhal.
Stereotaxis: Use of a computer and scanning devices to create
three-dimensional pictures. This method can be used to direct a
biopsy, external radiation, or the insertion of radiation
implants.
Steroids: A large group of chemical substances classified by
chemical structure. Steroids include drugs used to relieve
swelling and inflammation (such as prednisone), vitamin D, and
sex steroids (such as testosterone).
Still’s disease: Also known as systemic-onset juvenile
rheumatoid arthritis and systemic-onset juvenile chronic
arthritis. Still’s disease presents with systemic (bodywide)
illness including high intermittent fever, a salmon-colored skin
rash, swollen lymph glands, enlargement of the liver and spleen,
and inflammation of the lungs (pleuritis) and around the heart (pericarditis).
The arthritis may not be immediately apparent but it does appear
in time and may persist after the systemic symptoms are gone.
Still’s disease, adult-onset: (See Still’s disease.) Although
Still’s disease was first described in children, it is known to
occur in adults.
Stings, insect: Stings from large stinging insects such as
yellow jackets, bees, hornets and wasps can trigger allergic
reactions varying greatly in severity. Avoidance and prompt
treatment are essential. In selected cases, allergy injection
therapy is highly effective. (The three "A’s" of insect allergy
are Adrenaline, Avoidance and Allergist.)
Stoma: An opening into the body from the outside created by a
surgeon.
Stomach: A muscular pouch that helps in the digestion of food by
mixing it with digestive juices and churning it into a thin
liquid.
Stomach cancer: Cancer of the major organ that holds food for
digestion. Stomach cancer (gastric cancer) can develop in any
part of the stomach and spread to other organs. Stomach ulcers
do not appear to increase a person’s risk of developing stomach
cancer. Symptoms of stomach cancer are often vague, such as loss
of appetite and weight. The cancer is diagnosed with a biopsy of
stomach tissue during a procedure.
Stomach flu: A misnomer that has nothing to do with influenza
(flu) virus, the term "stomach flu" is sometimes used to
describe gastrointestinal illnesses caused by other
microorganisms.
Stomach, Pavlov: A pouch fashioned surgically from part of the
stomach (but isolated from the rest of the stomach) that opens
via a fistula (canal) on to the abdominal wall. At different
points along the dogs’ digestive tracts, the Russian
physiologist Ivan Petrovich Pavlov (1848-1936) surgically
created pockets ("Pavlov pouches") from which he could obtain
secretions, the aim being to study the physiology of the
digestive tract. He did so from the salivary glands down to the
stomach, liver and pancreas with considerable success and in
1904 (the 4th year it was awarded) he received the Nobel Prize
for "his work on the physiology of digestion, through which
knowledge on vital aspects of the subject has been transformed
and enlarged."
Stool: The solid matter discharged in a bowel movement.
Stool test: A test to see whether there is blood in the bowel
movement. Also called a fecal occult blood test: A test to check
for hidden blood in stool. (Fecal refers to stool. Occult means
hidden.)
Strep: Very commonly used shortened form of Streptococcus, a
very common and important group of bacteria. See Streptococcus
Strep throat: An infection caused by a type of bacteria called
streptococcus, which can lead to serious complications if not
adequately treated.
Streptococcus: A group of bacteria, familiarly known as strep,
that can > (and do) cause a multitude of diseases. The name
comes from the Greek strepto- meaning twisted + kokkos meaning
berry, and that is exactly what Strep look like under the
microscope, like a twisted bunch of little round berries. (In
technical terms, these are gram-positive, facultative anaerobic
cocci). Illness caused by strep includes strep throat, strep
pneumonia, scarlet fever, rheumatic fever (and rheumatic heart
valve damage) and > glomerulonephritis.
Stricture, esophagus, acute: A narrowing or closure of the
normal opening of the swallowing tube leading to the stomach,
usually caused by scarring from acid irritation. Acute, complete
obstruction of the esophagus occurs when food (usually meat) is
lodged in the esophageal stricture. Patients experience chest
pain, and are unable to swallow saliva. Attempts to relieve the
obstruction by inducing vomiting at home are usually
unsuccessful. Patients with complete esophageal obstruction can
breathe, and are not at any risk of suffocation. Endoscopy is
usually employed to retrieve the meat and relieve the
obstruction.
Stricture of the esophagus, chronic: A narrowing or closure of
the normal opening of the swallowing tube leading to the
stomach, usually caused by scarring from acid irritation. A
common complication of chronic gastroesophageal reflux disease (GERD).
Several procedures are available for stretching (dilating) the
strictures without having to resort to surgery. One of the
procedures involves placing a deflated balloon across the
stricture at the time of endoscopy. The balloon is then
inflated, thereby opening the narrowingcaused by the stricture.
Another method involves inserting tapered dilators of different
sizes through the mouth into the esophagus to dilate the
stricture.
STS: Sequence tagged site, a short (200 to 500 base pairs) DNA
sequence that occurs but once in the human genome and whose
location and base sequence are known. Detectable by polymerase
chain reaction, STSs are useful for localizing and orienting the
mapping and sequence data reported from many different
laboratories and serve as landmarks on the developing physical
map of the human genome. Expressed sequence tags (ESTs) are STSs
derived from cDNAs (complementary DNAs).
Study, cross-sectional: A study done at one time, not over the
course of time. A cross-sectional study a disease such as AIDS
might be designed to learn its prevalence and distribution
within the population at one point in time. Also known as a
synchronic study.
Study, diachronic: See: Study, longitudinal.
Study, longitudinal: A study done over the passage of time. For
example, a longitudinal study of children with Down syndrome (trisomy
21) might involve the study of 100 children with this condition
from birth to 10 years of age. Also called a diachronic study.
The opposite of a cross-sectional (synchronic) study.
Study, synchronic: See: Study, cross-sectional.
Subglottis: The lower part of the larynx; the area from just
below the vocal cords down to the top of the trachea.
Sublingual gland: The smallest of the three major salivary
glands. It is located. It lies under the floor of the mouth
close to the midline.
Subluxation: Partial dislocation of a joint. A complete
dislocation is a luxation.
Submandibular gland: The second largest of the three major
salivary glands. It is located deep to the mandible (jaw bone).
Submaxillary gland: See Submandibular gland.
Subtotal hysterectomy: The uterus is sugically removed but the
cervix is left is left in place. Also called a partial
hysterectomy.
Succenturiate: In anatomy "succenturiate" means substituting for
or accessory to an organ. For example, see Succenturiate
placenta. Succenturiate placenta: An extra placenta separate
from the main placenta. In anatomy "succenturiate" means
substituting for or accessory to an organ. In this case, a
succenturiate placenta is an accessory placenta.
Succenturiate placenta: An extra placenta separate from the main
placenta. In anatomy "succenturiate" means substituting for or
accessory to an organ. In this case, a succenturiate placenta is
an accessory placenta.
Sudden Infant Death Syndrome (SIDS): The sudden and unexpected
death of a baby with no known illness, typically affecting
infants from 2 weeks to 6 months of age while sleeping. At
elevated risk for SIDS are children with a brother or sister who
died of SIDS; babies whose mothers smoked or used heroin,
methadone, or cocaine during pregnancy; infants born weighing
less than 4.4 pounds (2000 grams); children with an abnormal
breathing pattern with long periods without taking a breath
(apnea); .and babies who sleep on their stomachs. Since babies
who sleep on their stomachs are at least 3 times more likely to
die of SIDS than babies who sleep on their backs, children’s
health authorities such as the American Academy of Pediatrics
recommend always placing infants on their backs to sleep.
Sulcus: From the Latin for a groove, furrow, or trench. In
medicine, there are many sulci (plural of sulcus) as, for
example, the superior pulmonary sulcus.
Sun protection factor (SPF): A number on a scale (from 2
upwards) for rating sunscreens. Sunscreens with an SPT of 15 or
higher provide the best protection from the sun's harmful rays.
Sunscreen: A substance that blocks the effect of the sun's
harmful rays. Using lotions that contain sunscreens can reduce
the risk of skin cancer, including melanoma.
Supernumerary: Beyond the normal number. Anything supernumerary
is extra.
Supernumerary digit: An extra finger or toe.
Supernumerary nipple: An extra nipple.
Supernumerary placenta: A succenturiate or accessory placenta.
Supination: Rotation of the arm or leg outward. In the case of
the arm, the palm of the hand will face forward.
Supine: Lying on the back.
Supportive care: Treatment given to prevent, control, or relieve
complications and side effects and to improve the patient's
comfort and quality of life.
Supraglottis: The upper part of the larynx, including the
epiglottis; the area above the vocal cords.
Suprarenal gland: See adrenal gland.
Suprasternal notch: The V shaped notch at the top of the
breastbone (sternum).
Surgery: An operation.
Suture: This word has several meanings depending on context. 1)
A type of bone joint where two bones are held tightly together
by fibrous tissue as in the skull. 2) Thread-like material used
to sew tissue. 3) To stitch a wound closed.
Swimming pool granuloma: Localized nodular skin inflammation
(small reddish raised areas of skin) caused by a bacterium
called mycobacterium marinum. Swimming pool granuloma is
typically acquired by occupational or recreational exposure to
salt or fresh water, often resulting from minor trauma during
caring for aquariums. The diagnosis is suggested by the history
of exposure and confirmed by culturing tissue specimens which
yield the microscopic organism, mycobacterium marinum. The
infection can be treated with a variety of antibiotics,
including doxycycline, minocycline, clarithromycin, rifampin,
and trimethoprim-sulfamethoxazole. Also called "fish bowl
granuloma."
Sympathetic nervous system: A part of nervous system that serves
to accelerate the heart rate, constrict blood vessels, and raise
blood pressure. The sympathetic nervous system, together with
the parasympathetic nervous system (that slows the heart rate,
increases intestinal and gland activity, and relaxes sphincter
muscles), constitutes the autonomic nervous system.
Symphysiotomy: A surgical procedure to effect an immediate
dramatic increase in the size of the pelvic outlet to permit
delivery of a baby. The cartilage of the symphysis pubis (where
the pubic bones come together) is surgically divided in the
procedure which can be a life-saver for the baby.
Symphysis pubis: The Greek word "symphysis" means growing
together. The "pubis" are the pubic bone. So the symphysis pubis
is where the pubic bones meet (in the front of the pelvis).
Symptom: Any abnormal change in appearance, sensation, or
function experienced by a patient which indicates a disease
process.
Synchronic: From the Greek syn-, together + chronos, time =
together in time. A synchronic study is a study done all
together at one point in time rather than longitudinally over
the course of time.
Syncope: Fainting represented by a partial or complete loss of
consciousness.
Syndrome: A syndrome is the combination of symptoms and signs
which together represent a disease process.
Syndrome, acquired immunodeficiency: AIDS.
Syndrome, antiphospholipid antibody: An immune disorder
characterized by the presence of abnormal antibodies in the
blood associated with certain medical conditions including
abnormal blood clotting, migraine headaches, premature
miscarriage, and low blood platelet counts (thrombocytopenia).
Syndrome, Barlow’s: Barlow’s syndrome is mitral valve prolapse
(also known as "click murmur syndrome"), the most common heart
valve abnormality, affecting 5-10% of the world population. Most
patients have no symptoms and require no treatment. However, the
condition can be associated with fatigue and/or palpitations.
The mitral valve prolapse can often be detected by a doctor
during examination of the heart and can be confirmed with an
echocardiogram. Patients are usually given antibiotics prior to
any procedure which might introduce bacteria into the
bloodstream, including dental work and minor surgery.
Syndrome, Behcet’s: Behcet’s syndrome is classically
characterized as a triad of symptoms that include recurring
crops of mouth ulcers (called apthous ulcers), genital ulcers,
and inflammation of a specialized area around the pupil of the
eye, the uvea. (The inflammation is called uveitis.) The cause
of Behcet’s syndrome is not known. The disease is more frequent
and severe in patients from the Eastern Mediterranean and Asia
than those of European descent.
Syndrome, Bernard: A complex of abnormal findings, namely
sinking in of one eyeball, ipsilateral ptosis (drooping of the
upper eyelid on the same side) and miosis (constriction of the
pupil of that eye) together with anhidosis (lack of sweating)
and flushing of the affected side of the face. Due to paralysis
of certain nerves (specifically, the cervical sympathetic
nerves). Also called Horner-Bernard syndrome, Bernard-Horner
syndrome and Horner’s ptosis but best known today as Horner
syndrome.
Syndrome, Bloch-Sulzberger: Also known as incontinentia pigmenti
(IP). A genetic disease with blisters that develop soon after
birth on the trunk and limbs, then heal, but leave dark (hyperpigmented)
streaks and marble-like whorls on the skin. (The name came from
the erroneous idea that the skin cells were incontinent of
pigment and could not contain it normally.) Other key features
of IP include dental and nail abnormalities, bald patches, and
(in about 1/3rd of cases) mental retardation. IP is an X-linked
dominant with male lethality. The IP gene is in band q28 on the
X chromosome. Mothers with IP have an equal chance of having a
normal or IP daughter or a normal son. The IP sons die before
birth. IP is also known as Bloch-Sulzberger syndrome.
Syndrome, Conn’s: Overproduction of the hormone aldosterone from
a tumor containing tissue like that in the outer portion
(cortex) of the adrenal gland. Excess aldosterone (pronounced
al-do-ster-one) results in low potassium levels (hypokalemia),
underacidity of the body (alkalosis), muscle weakness, excess
thirst (polydipsia), excess urination (polyuria), and high blood
pressure (hypertension). Also called primary aldosteronism and
hyperaldosteronism. Named after the American physician Jerome W.
Conn.
Syndrome, cracked tooth: A toothache caused by a broken tooth
(tooth fracture) without associated cavity or advanced gum
disease. Biting on the area of tooth fracture can cause severe
sharp pains. These fractures are usually due to chewing or
biting hard objects such as hard candies, pencils, nuts, etc.
Sometimes, the fracture can be seen by painting a special dye on
the cracked tooth. Treatment usually is to protect the tooth
with a crown. However, if placing a crown does not relieve pain
symptoms, a root canal procedure may be necessary.
Syndrome, Creutzfeldt-Jakob: Better known as Creutzfeldt-Jakob
disease (CJD). A dementing disease of the brain. It is believed
due to an unconventional (not a bacteria or virus),
transmissible agent called a prion. Symptoms of CJD include
forgetfulness, nervousness, jerky trembling hand movements,
unsteady gait, muscle spasms, chronic dementia, balance
disorder, and loss of facial expression. CJD is classified as a
spongiform encephalopathy. Most cases occur randomly
(sporadically), but inherited forms exist. There is neither
treatment nor cure for CJD. Other names for CJD include
Jakob-Creutzfeldt disease and spastic pseuodoparalysis.
Syndrome, Cushing’s: The constellation of symptoms and signs
caused by an excess of cortisol hormone. Cushing syndrome is an
extremely complex hormonal condition that involves many areas of
the body. Common symptoms are thinning of the skin, weakness,
weight gain, bruising, hypertension, diabetes, thin weak bones
(osteoporosis), facial puffiness, and in women cessation of
periods. Ironically, one of the commonest causes of Cushing’s
syndrome is the administration of "cortisol-like medications"
for the treatment of diverse diseases. All other cases of
Cushing’s syndrome are due to excess production of cortisol by
the adrenal gland including 1) an abnormal growth of the
pituitary gland, which stimulates the adrenal gland, 2) a benign
or malignant growth within the adrenal gland itself, which
produces cortisol and 3) production within another part of the
body (ectopic production) of a hormone that directly or
indirectly stimulates the adrenal gland to make cortisol.
Neurosurgeon Harvey Cushing (1869-1939) described
hyperadrenocorticism (excessive production of cortisol by the
adrenal gland) due quite specifically to an ACTH-secreting
pituitary adenoma, a benign pituitary tumor that puts out ACTH (AdrenoCorticoTropic
Hormone) which, in turn, drives (or overdrives) the adrenal
gland to overproduce cortisol.
Syndrome, DiGeorge (DGS): This disorder is characterized by (1)
low blood calcium levels (hypocalcemia) due to underdevelopment
(hypoplasia) of the parathyroid glands which control calcium;
(2) underdevelopment (hypoplasia) of the thymus, an organ behind
the breastbone in which lymphocytes mature and multiply; and (3)
defects of the heart involving the outflow tracts from the
heart. Most cases of DGS are due to a microdeletion in
chromosome band 22q11.2. A small number of cases have defects in
other chromosomes, notably 10p13. Named after the American
pediatric endocrinologist Angelo > DiGeorge. Other names for DGS
include the third and fourth pharyngeal pouch syndrome and
hypoplasia of the thymus and parathyroids.
Syndrome, Down: A common disorder due to a chromosome
abnormality and specfically due to an extra chromosome number 21
(trisomy 21). Down syndrome includes mental retardation, a
characteristic face, and multiple malformations. It is
associated with a major risk for heart problems, a lesser risk
of duodenal atresia (part of the intestines not developed), and
a minor but still significant risk of acute leukemia. The name
Down syndrome comes from the 19th century English doctor Langdon
Down, a misnomer since he was curiously enough not the first
person to describe the condition and, in great error, attributed
the condition to a "reversion" to the mongoloid race. Hence, the
old name mongolism, now considered slang.
Syndrome, dumping: A group of symptoms that occur when food or
liquid enters the small intestine too rapidly. These symptoms
include cramps, nausea, diarrhea, and dizziness.
Syndrome, Edwards: This is trisomy 18 syndrome. There are three
instead of the normal two chromosomes #18. Children with this
condition have multiple malformations and mental retardation due
to the extra chromosome #18. The children characteristically
have low birth weight, small head (microcephaly), small jaw (micrognathia),
malformations of the heart and kidneys, clenched fists with
abnormal finger positioning, and malformed feet. The mental
retardation is profound with the IQ too low to even test.
Nineteen out of 20 (95%) of these children die before their
first birthday. The condition is named after the British
physician and > geneticist John Edwards who discovered the extra
chromosome in 1960.
Syndrome, fetal alcohol (FAS): The sum total of a person’s
problems caused by maternal alcohol intake during pregancy.
Syndrome, fish-odor: An inborn error of metabolism associated
with an offensive body odor, the smell of rotting fish, due to
the excessive excretion of trimethylaminuria (TMA) in urine,
sweat, and breath. Persons with TMA may experience tachycardia
(fast heart rate) and severe hypertension (high blood pressure)
after eating cheese (which contains tyramine) and after using
nasal sprays containing epinephrine. TMA is caused by a mutation
(change) in the gene for an enzyme, flavin-containing
monooxygenase-3 (FMO3) encoded by a gene on chromosome #1. The
FMO3 enzyme metabolizes tyramine (which is in cheese). The
syndrome is associated with various psychosocial reactions,
including social isolation, clinical depression and attempted
suicide.
Syndrome, floppy baby: Floppy baby syndrome is a general medical
reference to an abnormal condition of newborns and infants
manifest by inadequate tone of the muscles. Hypotonia
(inadequately toned muscles resulting in floppiness) in the
newborn period and infancy can be due to a multitude of
different neurologic and muscle problems.
Syndrome, fragile X: The most common heritable form of mental
retardation. Fragile X syndrome is due to mutation (changes) at
the fragile X site and so perforce is X-linked (carried on the X
chromosome). Although it is usually more severe in males than
females, the syndrome is due to a dynamic mutation (a
trinucleotide repeat) that can change in length and hence in
severity from generation to generation, from person to person,
and even within a given person. The fragile X syndrome is also
known as the Martin-Bell syndrome in honor of their discovery of
it in 1943.
Syndrome, Hecht: Inherited disorder transmitted as an autosomal
dominant trait in which short tight muscles make it impossible
to open the mouth fully or keep the fingers straight when the
hand is flexed back. The small mouth creates feeding problems.
The hands may be so tightly fisted the infant crawls on the
knuckles. Also called the trismus pseudocamptodactyly syndrome.
Syndrome, Horner: A complex of abnormal findings, namely sinking
in of one eyeball, ipsilateral ptosis (drooping of the upper
eyelid on the same side) and miosis (constriction of the pupil
of that eye) together with anhidosis (lack of sweating) and
flushing of the affected side of the face. Due to paralysis of
certain nerves (specifically, the cervical sympathetic nerves).
Also called Horner-Bernard syndrome, Bernard syndrome,
Bernard-Horner syndrome and Horner’s ptosis but far and away
best known as Horner syndrome.
Syndrome, Hurler: A genetic error of metabolism. There is
incomplete breakdown and accumulation of a substance (a
mucopolysaccharide) which is abnormally stored in the brain and
other places. This usually leads to death of the individual with
Hurler syndrome by their early teen years. See gargoylism.
Syndrome, incontinentia pigmenti (IP): A genetic disease with
blisters that develop soon after birth on the trunk and limbs,
then heal, but leave dark (hyperpigmented) streaks and
marble-like whorls on the skin. (The name came from the
erroneous idea that the skin cells were incontinent of pigment
and could not contain it normally.) Other key features of IP
include dental and nail abnormalities, bald patches, and (in
about 1/3rd of cases) mental retardation. IP is an X-linked
dominant with male lethality. The IP gene is in band q28 on the
X chromosome. Mothers with IP have an equal chance of having a
normal or IP daughter or a normal son. The IP sons die before
birth. IP is also known as Bloch-Sulzberger syndrome.
Syndrome, irritable bowel (IBS): A common gastrointestinal
disorder (also called spastic colitis, mucus colitis or nervous
colon syndrome), IBS is an abnormal condition of gut
contractions (motility) characterized by abdominal pain,
bloating, mucous in stools, and irregular bowel habits with >
alternating diarrhea and constipation, symtoms that tend to be
chronic and wax and wane over the years. Although IBS can cause
chronic recurrent discomfort, it does not lead to any serious
organ problems. Diagnosis usually involves > excluding other
illnesses. Treatment is directed toward relief of symptoms and
includes high fiber diet, exercise, relaxation techniques,
avoidance of caffeine, milk products and sweeteners, and
medications.
Syndrome, joint hypermobility: See Syndrome, hypermobility.
Syndrome, Kartagener’s : The trio of sinusitis, bronchitis and
situs inversus (lateral reversal of the position all organs in
the chest and abdomen with the heart and stomach on the right,
the liver on the left, etc.—opposite or "inverted" from their
usual position).
Syndrome, kinky hair: Genetic disorder with fragile twisted
("kinky") hair and progressive deterioration of the brain. Due
to an error in copper transport resulting in copper deficiency.
Females are carriers and their sons with the gene have the
disease. Also known as Menkes syndrome.
Syndrome, Klinefelter: The most common single cause of
hypogonadism (underfunction of the gonads) and infertility in
men, Klinefelter syndrome is due to a chromosome abnormality
with XXY (plus additional X or Y chromosomes). It affects about
1 in 500 males and results in small testes (hypogenitalism),
underproduction of testosterone and infertility (hypogonadism),
and a long-limbed, long-trunked, relatively tall, slim build.
Klinefelter boys tend to have learning and/or behavioral
problems. At adolescence there is little growth of facial hair
and a third of boys develop gynecomastia (enlargement of the
male breast). Named for the physician Harry Klinefelter who with
E.C. Reifenstein, Jr. and Fuller Albright (the founder of modern
endocrinology) described the condition in 1942 long before its
chromosomal basis became known.
Syndrome, Klippel-Feil: The combination of short neck, low
hairline at the nape of the neck and limited movement of the
head. It is due to a defect in the early development of the
spinal column in the neck (the cervival vertebrae). The
condition is also called the Klippel-Feil sequence (referring to
an embryologic or early developmental sequence of events).
Syndrome, Li-Fraumeni: A family tendency to cancers due to a
mutation in a gene that normally serves to curb cancer: the p53
tumor-suppressor gene. Named after Drs. Fred Li and Joe Fraumeni.
Syndrome, Lennnox: See Syndrome, Lennox-Gastaut.
Syndrome, Lennox-Gastaut: A severe form of epilepsy that usually
begins in early childhood and is characterized by frequent
seizures of multiple types, mental impairment, and a particular
brain wave pattern (a slow spike-and-wave pattern). The seizures
that are notoriously hard to treat and may lead to falls and
injuries can be reduced in frequency by treatment with
lamotrigone, a chemically novel antiepileptic drug. The syndrome
is named for W.G. Lennox and H. Gastaut who described it.
Syndrome, Marfan: Inherited disorder with long fingers and toes,
dislocation of the lens, and aortic wall weakness and aneurysm.
(It has been suggested that Abraham Lincoln had Marfan
syndrome.)
Syndrome, Martin-Bell: Better known as the fragile X syndrome,
the most common heritable form of mental retardation. Fragile X
syndrome is due to mutation (changes) at the fragile X site and
so perforce is X-linked (carried on the X chromosome). Although
it is usually more severe in males than females, the syndrome is
due to a dynamic mutation (a trinucleotide repeat) that can
change in length and hence in severity from generation to
generation, from person to person, and even within a given
person. The fragile X syndrome is known as the Martin-Bell
syndrome in honor of their discovery of it in 1943.
Syndrome, mucocutaneous lymph node: A syndrome of unknown
origin, mainly affecting young children, causing fever,
reddening of the eyes > (conjunctivitis), lips and mucous
membranes of the mouth, ulcerative gum disease (gingivitis),
swollen glands in the neck (cervical > lymphadenopathy), and a
rash that is raised and bright red (maculoerythematous) in a
glove-and-sock fashion over the skin of the hands and feet which
becomes hard, swollen (edematous), and peels off. Also called
Kawasaki’s disease.
Syndrome, Munchhausen: Recurrent feigning of catastrophic
illnesses. Named for the fictitious Baron who told tales that
were whopping lies.
Syndrome, myelodysplastic: A condition in which the bone marrow
does not function normally. It does not produce enough blood
cells. This condition may progress and become acute leukemia.
Myelodysplastic syndrome also is called preleukemia or
smoldering leukemia.
Syndrome, nail-patella: Hereditary dominant condition with
abnormally formed (dysplastic) or absent nails and absent or
underdeveloped (hypoplastic) kneecaps (patellae). Other features
include iliac horns (symmetrical bilateral central posterior
iliac processes), abnormality of the elbows interfering with
full range of motion (pronation and supination) and kidney
disease resembling glomerulonephritis which.is often mild but
can be progressive and lead to renal failure. The nail-patella
gene locus found linked genetically to the ABO blood group
in1965 is now known to be in chromosome region 9q34. Also called
onychoosteodysplasia, Turner-Kieser syndrome, and Fong disease.
Syndrome, nervous colon: See Syndrome, irritable bowel.
Syndrome, Pallister-Killian: Condition with multiple
malformations at birth and mental retardation due to
isochromosome 12p mosaicism (an abnormal chromosome #12 in some
cells).
Syndrome, Patau: Trisomy 13 syndrome or three chromosome number
13s instead of the normal two. Children with this condition have
multiple malformations and mental retardation due to an extra
chromosome #13 Named after the late Klaus Patau who described
the extra chromosome in 1960. This is trisomy 13 syndrome. There
are three rather than the normal two chromosomes #13. Children
with this syndrome have multiple malformations and mental
retardation due to the extra chromosome #13. The malformations
commonly include scalp defects, hemangiomas (blood vessel
malformations) of the face and nape of the neck, cleft lip and
palate, malformations of the heart and abdominal organs, and
flexed fingers with extra digits. The mental retardation is
profound. The IQ is untestably low. The majority of trisomy 13
babies die soon after birth or in infancy. Named after the late
Klaus Patau who discovered the extra chromosome in 1960.
Syndrome, Pickwickian: The combination of obesity, somnolence,
hypoventilation (underbreathing), and plethoric (red) face named
after the "fat and red-faced boy in a state of somnolency" in
Charles Dickens’ novel The Pickwick Papers. (The same boy is
thought by some to have had Prader-Willi syndrome).
Syndrome, popliteal pterygium: An inherited condition with a web
behind the knee. (A pterygium is a winglike triangular
membrane.)
Syndrome, Prader-Willi: A condition in children with floppiness
(hypotonia), obesity, small hands and feet and mental
retardation. It is due to loss of part or all of chromosome 15,
specifcally the chromosome 15 from the father. The "fat and
red-faced boy in a state of somnolency" described by Charles
Dickens in his novel The Pickwick Papers is thought by some to
have had Prader-Willi syndrome. (The same boy inspired the
naming of the Pickwickian syndrome).
Syndrome premenstrual (PMS): A combination of emotional,
physical, psychological, and mood disturbances that occur after
ovulation and normally end with the onset of the menstrual flow.
Syndrome, Proteus: A disturbance of cell growth including benign
tumors under the skin, overgrowth of the body, often more on one
side than the other (hemihypertrophy), and overgrowth of fingers
(macrodactyly). The syndrome is named after the Greek god
Proteus the polymorphous who could change his appearance. The
"elephant man" (John MerricK) of 19th century England who was
thought to have had neurofibromatosis probably had Proteus
syndrome.
Syndrome, radial aplasia-thrombocytopenia: See Syndrome, TAR.
Syndrome, reflex sympathetic dystrophy (RSDS): A condition that
features a group of typical symptoms, including pain (often
"burning" type), tenderness, and swelling of an extremity
associated with varying degrees of sweating, warmth and/or
coolness, flushing, discoloration, and shiny skin.
Syndrome, Reiter’s: A chronic form of inflammatory arthritis
wherein the following three conditions are combined: (1)
arthritis; (2) inflammation of the eyes (conjunctivitis); and
(3) inflammation of the genital, urinary or gastrointestinal
systems.
Syndrome, Reye’s: A sudden, sometimes fatal, disease of the
brain > (encephalopathy) with degeneration of the liver, occurs
in children (most cases 4-12 years of age), comes after the
chickenpox (varicella) or an influenza-type illness, is also
associated with taking medications containing aspirin. The child
with Reye’s syndrome first tends to be unusually quiet,
lethargic (stuporous), sleepy, and vomiting. In the second
stage, the lethargy deepens, the child is confused, combative
and delirious. And things get worse from there with decreasing
consciousness, coma, seizures, and eventually death. The
prognosis (outlook) depends on early diagnosis and control of
the increased intracranial pressure. Reye’s syndrome is a good
reason to have your child immunized against chickenpox and not
give a child aspirin for fever.
Syndrome, scalded skin: See Scalded skin syndrome.
Syndrome, Shprintzen: Congenital malformation (birth defect)
syndrome with cleft palate, heart defect, abnormal face, and
learning problems.The condition is also called the velo-cardio-facial
(VCF) syndrome. (The velum is the soft palate). Other less
frequent features include short stature, small-than-normal head
(microcephaly), mental retardation, minor ear anomalies, slender
hands and digits, and inguinal hernia. The cause is usually a
microdeletion in chromosome band 22q11.2, just as in DiGeorge
syndrome. Shprintzen and DiGeorge syndromes are different
clinical expressions of essentially the same chromosome defect.
Syndrome, Stein-Leventhal: Known descriptively as polycystic
ovarian disease (PCO), this syndrome is basically an hormonal
problem that causes women to have a variety of symptoms
including irregular or no periods, acne, obesity and excessive
hair growth. Women with PCO are at a higher risk for uterine
cancer (endometrial cancer), diabetes, high blood pressure, and
heart disease. With proper treatment, risks can be minimized.
The syndrome is named after the late American gynecologists
Irving F. Stein, Sr. and Michael Leo Leventhal.
Syndrome, Shulman’s (Eosinophilic fasciitis): A disease which
leads to inflammation and thickening of the skin and fascia.
(The fascia is a lining tissue under the skin that covers a
surface of underlying tissues.) When the fascia is inflamed, the
condition is referred to as "fasciitis." In eosinophilic
fasciitis, the involved fascia is inflamed with the eosinophil
white blood cells. There is progressive thickening, and often
redness and warmth, and hardness of the skin surface.
Syndrome, TAR: TAR stands for Thrombocytopenia (low blood
platelets) and Aplasia (absence) of the Radius (the long bone on
the thumb-side of the forearm), features characterizing this
syndrome. There is phocomelia > (flipper-limb) with the thumbs
always present. The fibula (the smaller bone in thye lower leg)
is often absent. The risk of bleeding from too few platelets is
high in early infancy but lessens with age. The condition is
inherited in an autosomal recessive trait with one gene (on a
non-sex chromosome) coming from each parent to the TAR child.
Alternative names include > thrombocytopenia-absent radius
syndrome, radial aplasia-thrombocytopenia syndrome, and
tetraphocomelia-thrombocytopenia syndrome.
Syndrome, tempero-mandibular joint: Disorder of the
temporo-mandibular joint(TMJ) causing pain usually in front of
the ear. Pain in the TMJ can be due to trauma (such as a blow to
the face), inflammatory or degenerative arthritis, or by the
mandible being pushed back towards the ears whenever the patient
chews or swallows. Sometimes, muscles around the TMJ used for
chewing can go into spasm, causing head and neck pain and
difficulty opening the mouth normally.
Syndrome, tetraphocomelia-thrombocytopenia: See Syndrome, TAR.
Syndrome, third and fourth pharyngeal pouch: See Syndrome,
DiGeorge.
Syndrome, thoracic outlet: Condition due to compromise of blood
vessels or nerve fibers between the armpit (axilla) and base of
the neck.
Syndrome, thrombocytopenia-absent radius: See Syndrome, TAR.
Syndrome, TMJ: Disorder of the temporo-mandibular joint (TMJ)
causing pain usually in front of the ear. Pain in the TMJ can be
due to trauma (such as a blow to the face), inflammatory or
degenerative arthritis, or by the mandible being pushed back
towards the ears whenever the patient chews or swallows.
Sometimes, muscles around the TMJ used for chewing can go into
spasm, causing head and neck pain and difficulty opening the
mouth normally.
Syndrome, toxic shock: A grave condition occurring predominantly
in menstruating women using tampons, toxic shock is
characterized by a highly toxic state (with sudden high fever,
vomiting, diarrhea, muscle aching) followed by low blood
pressure (hypotension) which can lead to shock (and death).
There may be a rash resembling sunburn with peeling of skin. The
Channing Laboratory in Boston under Dr. Edw. Kass discovered
that toxic shock was due to a toxin produced by Staph
(Staphylococcus) aureus bacteria growing under conditions with
little or no oxygen. The syndrome occurs rarely in women not
using tampons and in men.
Syndrome, trisomy 13: Condition with three rather than the
normal two chromosomes #13. Children born with this syndrome
have multiple malformations and mental retardation due to the
extra chromosome #13. The congenital malformations (birth
defects) commonly include scalp defects, > hemangiomas > (blood
vessel malformations) of the face and nape of the neck, cleft
lip > and palate, malformations of the heart and abdominal
organs, and flexed fingers with extra digits. The mental
retardation is profound. The IQ is untestably low. The majority
of trisomy 13 babies die soon after birth or in infancy. The
condition is also called Patau syndrome after the late
geneticist Klaus Patau > (at the University of Wisconsin) who
discovered the extra chromosome in 1960.
Syndrome, trisomy 18: There are three instead of the normal two
chromosomes #18. Children with this condition have multiple
malformations and mental retardation due to the extra chromosome
#18. The children characteristically have low birth weight,
small head (microcephaly), small jaw (micrognathia),
malformations of the heart and kidneys, clenched fists with
abnormal finger positioning, and malformed feet. The mental
retardation is profound with the IQ too low to edven test.
Nineteen out of 20 (95%) of these children die before their
first birthday. The condition is also called Edwards syndrome in
honor of the British physician and geneticist John Edwards who
discovered the extra chromosome in 1960.
Syndrome, trisomy 21: A common chromosome disorder due to an
extra chromosome number 21 (trisomy 21). The syndrome causes
mental retardation, a characteristic face, and multiple
malformations. It is associated with a major risk for heart
problems, a lesser risk of duodenal atresia (part of the
intestines not developed), and a minor but still significant
risk of acute leukemia. Trisome 21 syndr0ome is also commonly
called Down syndrome after the 19th century English doctor
Langdon Down who was curiously enough not the first person to
describe the condition, added little to knowledge and, in great
error, attributed the condition to a "reversion" to the
mongoloid race. The disorder was also once called mongolism, a
term now considered slang.
Syndrome, Turner-Kieser: See nail-patella syndrome Turner in
1933 described two families with the disease. The name Turner is
more closely associated with the XO syndrome.
Syndrome, yeast: The yeast Candida has been thought to cause a
syndrome with a number of nonspecific problems including
fatigue, loss of appetite, headache, short-attention span,
depression and all manner of intestinal irregularities. There is
no scientific evidence to support the existence of the yeast
syndrome (also called the yeast connection).
Synovia: The joint fluid. The term synovia was invented in 1520
by the Swiss physician (and alchemist) Paracelsus who combined
the Greek syn-(together) and oon (egg) to create a name for any
body fluid that looked like the white of an egg. Today, synovia
is restricted to the fluid that lubricates joints.
Synovial cyst, popliteal: A swelling in the space behind the
knee (the popliteal space). The swelling is composed of a
membrane-lined sac filled with synovial fluid that has escaped
from the joint. Commonly called Baker’s cyst.
Synovial fluid: The slippery fluid in joints. Also called the
synovia.
Synovial lining: The lining of the joint.
Synovitis: Inflammation of the synovial membrane, the lining of
the joint.
Syphilis: A sexually transmitted disease (STD) that has been
around for centuries and is caused by Treponema pallidum, a
microscopic organism called a spirochete, a worm-like
spiral-shaped organism that infects by burrowing into the moist
mucous membranes of the mouth or genitals. From there, the
spirochete produces the classic non-painful ulcer known as a
chancre. There are three stages of syphilis. The first
("primary") stage is formation of the chancre. It is highly
contagious and can last 1-5 weeks. The disease can be
transmitted from any contact with one of the ulcers, which are
teeming with spirochetes. If the ulcer is outside of the vagina
or on the scrotum of the male, the use of condoms may not help
in preventing transmission of the disease. Likewise, if the
ulcer is in the mouth, merely kissing the infected individual
can spread syphilis. Even without treatment, the early infection
resolves on its own in most women. However, 25% will proceed to
the next stage of the disease called "secondary" syphilis, which
lasts 4-6 weeks. This secondary phase can include hair loss, a
sore throat, white patches in the nose, mouth, and vagina,
fever, headaches, and a skin rash. There can be lesions on the
genitals that look like genital warts but are caused by
spirochetes rather than the wart virus. These wart-like lesions,
as well as the skin rash, are highly contagious. The rash can
occur on the palms of the hands and the infection can be
transmitted by casual contact. The third (‘tertiary") stage of
the disease involves the brain and heart and is usually no
longer contagious. At this point, however, the infection can
cause extensive damage to the internal organs, such as the
brain, and can lead to death.
System, autonomic nervous: Part of the nervous system once
thought functionally independent of the brain. The autonomic
nervous system regulates key functions including the activity of
the cardiac (heart) muscle, smooth muscles (e.g., of the gut),
and glands. The autonomic nervous system has two divisions: (1)
the sympathetic nervous system that accelerates the heart rate,
constricts blood vessels, and raises blood pressure; and (2) the
parasympathetic nervous system slows the heart rate, increases
intestinal and gland activity, and relaxes sphincter muscles.
System, parasympathetic nervous: A part of nervous system that
slows the heart rate, increases intestinal and gland activity,
and relaxes sphincter muscles. The parasympathetic nervous
system together with the sympathetic nervous system (that
accelerates the heart rate, constricts blood vessels, and raises
blood pressure) constitute the autonomic nervous system.
System, sympathetic nervous: A part of nervous system that
accelerates the heart rate, constricts blood vessels, and raises
blood pressure. The sympathetic nervous system together with the
parasympathetic nervous system (that slows the heart rate,
increases intestinal and gland activity, and relaxes sphincter
muscles) constitute the autonomic nervous system.
Systemic-onset juvenile chronic arthritis: See: Systemic-onset
juvenile rheumatoid arthritis (Still’s disease).
Systemic-onset juvenile rheumatoid arthritis (Still’s disease):
Also known as systemic-onset juvenile chronic arthritis. Still’s
disease presents with systemic (bodywide) illness including high
intermittent fever, a salmon-colored skin rash, swollen lymph
glands, enlargement of the liver and spleen, and inflammation of
the lungs (pleuritis) and around the heart (pericarditis). The
arthritis may not be immediately apparent but, once apparent, it
may persist after the systemic symptoms are gone.
Systemic therapy: Treatment that reaches cells throughout the
body by traveling through the bloodstream. |