Definitions

syndrome

toxic shock syndrome

Bacterial disease caused by a toxin produced by the bacterium Staphylococcus aureus. It was first recognized in 1978 in women using superabsorbent tampons. High fever, diarrhea, vomiting, and rash may progress to abdominal tenderness, drop in blood pressure, shock, respiratory distress, and kidney failure. The syndrome also has other causes, including postsurgical infection. Antibiotics are not effective. With intensive supportive therapy, most patients recover in 7–10 days, but 10–15percnt die. Many patients have a milder recurrence within eight months.

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or crib death

Unexpected death of an apparently well infant. It occurs almost always during sleep at night and usually at 2–4 months of age. Sleeping facedown and exposure to cigarette smoke have been implicated. It is more common in cases of premature birth, low birth weight, and poor prenatal care. Many cases that would once have been labeled SIDS prove to be due to suffocation in bedding or overheating. Some babies who die of SIDS have been found to have brain stem abnormalities that interfere with their response to high levels of carbon dioxide in the blood.

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in full severe acute respiratory syndrome

Highly contagious respiratory illness characterized by a persistent fever, headache, and bodily discomfort, followed by a dry cough that may progress to great difficulty in breathing. SARS appeared in November 2002 in Guangdong province, China, and was brought to Hong Kong in February 2003. As it spread from there to other countries of East Asia and the world, health authorities instituted an unprecedented series of control measures, including quarantines and prohibitions on travel, and in June 2003 the global outbreak was declared to be contained. By that time more than 8,000 cases had been reported, and some 800 people had died. SARS is believed to be caused by a mutant coronavirus, a type usually associated with pneumonia and the common cold. A specific vaccine has not been developed. Treatment is usually restricted to easing the patient's symptoms—providing mechanical ventilation if necessary—until the illness has run its course.

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or hyaline membrane disease

Common complication in newborns, especially after premature birth. Symptoms include very laboured breathing, bluish skin tinge, and low blood oxygen levels. Insufficient surfactant in the pulmonary alveoli raises surface tension, hampering lung expansion. The alveoli collapse (see atelectasis), and a “glassy” (hyaline) membrane develops in the alveolar ducts. Once the leading cause of death in premature infants, the syndrome is now usually treated for a few days with a mechanical ventilator (see respiratory therapy), with no aftereffects. An adult respiratory distress syndrome (ARDS) can follow lung injury.

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Variable group of symptoms occurring before menstruation in 40percnt of women, severe in about 10percnt of those. Physical symptoms may include headache, cramps, bloating, and constipation or diarrhea. Emotional symptoms range from irritability, lethargy, and mood swings to hostility, confusion, and depression. Theories as to the cause centre on hormones, nutrition, and stress (known to affect severity). Depending on the symptoms, treatment may involve exercise, stress management, nutritional therapy, or drugs. Dietary measures include low sodium and high protein and complex carbohydrate intake and avoidance of xanthines (including caffeine). Increasing calcium intake has been shown to prevent or reduce cramps, which are best treated with ibuprofen.

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Psychological reaction occurring after a highly stressful event and typically characterized by flashbacks, recurrent nightmares, and avoidance of reminders of the event; depression and anxiety are often present. Traumatic events that can lead to PTSD include automobile accidents, rape or assault, military combat, torture, and such natural disasters as floods, fires, or earthquakes. Long-term effects can include marital and family problems, difficulties at work, and abuse of alcohol and other drugs. Antidepressant medication and psychotherapy, including group therapy, are used in treating the disorder.

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or polycystic ovary syndrome (PCOS)

Endocrine disorder in women, characterized by high levels of male hormones (androgens) and infrequent or absent ovulation (see reproductive system). It causes a high proportion of female infertility cases. Symptoms vary but often include increased serum concentrations of androgens, insulin resistance, hirsutism, acne, and obesity. Menstruation may be irregular, absent, or excessive. The ovaries are usually enlarged and contain cysts. The disease may remain undiagnosed until a woman tries to conceive. The underlying cause is not fully understood, and no genetic mutations have been associated with the syndrome. Many women with Stein-Leventhal syndrome are at an increased risk of developing metabolic disorders such as type II diabetes or lipid disorders such as atherosclerosis at an unusually young age. Treatment attempts to reduce androgen production. Infertility may be treated with clomiphene citrate or gonadotropins to induce ovulation.

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The ability to feel sensations and pain in a limb or limbs that no longer exist. Phantom limb syndrome experienced by amputees is generally characterized by nonpainful sensations, such as the perception of movement and reception of external stimuli (e.g., touch, pressure, itch), and by painful sensations, such as the perception of burning, tingling, or shooting pains. The syndrome can be explained by map expansion neuroplasticity, in which the local brain region that once specialized in controlling the function of the amputated limb and that is reflected as a discrete “map” in the cerebral cortex of the brain is taken over by an adjacent brain map such as the face map, thereby expanding the face map. The acquisition of a part of the unused phantom map by the face map results in the perception of sensation in the amputated limb when the face is touched. Treatment of the syndrome may employ pain-relieving medications, coping techniques, nonsurgical treatments (including shock therapy and acupuncture), and implantable treatments, such as deep brain stimulation and spinal cord stimulation. Mirror box therapy has been successful in a small number of patients, primarily those who experienced paralysis of a limb prior to amputation and thus suffer from a condition known as “learned paralysis.”

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or IBS

Chronic disorder characterized by abdominal pain, intestinal gas, and diarrhea, constipation, or both. Other symptoms may include abdominal pain that is relieved after defecation or a sensation of incomplete rectal evacuation. IBS is caused by a motility disturbance of the intestines that may result from increased intestinal sensitivity to distension. Stress or the consumption of fatty foods, milk products, certain fruits or vegetables (e.g., broccoli and cabbage), alcohol, or caffeine may cause similar symptoms. Treatment includes relaxation, exercise, and avoidance of aggravating foods. Antidiarrheal medications or fibre supplements may help lessen symptoms. Although IBS may cause discomfort and emotional distress, the disorder does not result in any permanent intestinal damage.

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Various congenital disorders in a newborn caused by the mother drinking alcohol during pregnancy. The main symptoms are retarded growth, abnormalities of the central nervous system, and certain face and head abnormalities. The child may be mentally retarded. Behavioral problems (e.g., poor concentration, impulsiveness) are sometimes the only obvious symptoms. The syndrome is common in babies born to chronic alcoholics, but health care organizations now commonly recommend that women cease drinking alcohol entirely while pregnant. Other disorders have been linked to alcohol in breast milk.

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Sudden debilitating fatigue of unknown cause. It may follow a nonspecific illness with mild fever, tender lymph nodes, sore throat, headaches, weakness, muscle and joint pain, and confusion or difficulty in concentrating. To meet the criteria of CFS, the syndrome must be new, with a definite point of onset, and must persist more than six months. Once dismissed as imaginary, CFS remains controversial. Many authorities question whether it is a distinct disorder, since there is considerable overlap with other conditions such as fibromyalgia and Gulf War syndrome. No diagnostic test for CFS exists. Although a number of theories about the cause of CFS have been advanced, none has been proved. No cure has been found, but most patients improve gradually.

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Painful condition caused by repetitive stress to the wrist over time. The median nerve and the tendons that bend the fingers pass through the carpal tunnel on the inner side of the wrist, between the wrist (carpal) bones on three sides and a ligament on the fourth. Repetitive finger and wrist movements rub the tendons against the walls of the carpal tunnel and may make the tendons swell, squeezing the nerve. Numbness, tingling, and pain in the wrist and hand may progress to loss of muscle control. CTS is most common in assembly-line workers and computer keyboard users. Treatment may include avoidance of the causative activity, ergonomic workplace design, anti-inflammatory drugs, brace or splint use, and surgery.

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Crime of inflicting physical or emotional injury on a child. The term can denote the use of inordinate physical violence or verbal abuse; the failure to furnish proper shelter, nourishment, medical treatment, or emotional support; incest, rape, or other instances of sexual molestation; and the making of child pornography. Child abuse can cause serious harm to its victims. Estimates of the numbers of children who suffer physical abuse or neglect by parents or guardians range from about 1 percent of all children to about 15 percent, and figures are far higher if emotional abuse and neglect are included. In many cases, the abuser himself suffered abuse as a child. When abuse results in death, evidence of child abuse or battered-child syndrome (e.g., broken bones and lesions, either healed or active) is often used to establish that death was not accidental.

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in full acquired immunodeficiency syndrome

Transmissible disease of the immune system caused by HIV. AIDS is the last stage of HIV infection, during which time the individual develops frequently fatal infections and cancers, including Pneumocystis carinii pneumonia, cytomegalovirus (CMV), lymphoma, and Kaposi sarcoma. The first AIDS cases were identified in 1981, HIV was isolated in 1983, and blood tests were developed by 1985. According to the UN's 2004 report on AIDS, some 38 million people are living with HIV, approximately 5 million people become infected annually, and about 3 million people die each year from AIDS. Some 20 million people have died of the disease since 1981. Sub-Saharan Africa accounts for some 70 percent of all HIV infections. Rates of infection are lower in other parts of the world, but the epidemic is spreading rapidly in eastern Europe, India, South and Southeast Asia, Latin America, and the Caribbean.

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Chromosomal disorder (from the presence of only one sex chromosome, X, in all or some of the body's cells) that causes abnormal sexual development in females. The syndrome may include absent or undeveloped ovaries, underdeveloped secondary sex characteristics, low hairline, webbed neck, shield-shaped chest with wide-spaced nipples, and kidney and heart malformations with coarctation (narrowing) of the aorta. It may not be recognized until a girl fails to undergo puberty at a normal age. Estrogen treatment results in puberty, adult appearance, and normal sex drive but not fertility. Surgery can correct malformations.

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Acute neurological illness in children, following influenza, chickenpox, or other viral infections. Vomiting, lethargy, and confusion begin as the child appears to be recovering. These symptoms are followed hours or days later by drowsiness, disorientation, seizures, respiratory arrest, and coma. At worst, the syndrome includes fatty liver degeneration and potentially fatal brain swelling. There is no specific cure, but treatment of imbalances helps over 70percnt of patients survive (some with brain damage). The incidence has decreased since the recognition that it often follows use of aspirin or other salicylic acid derivatives in children during a viral illness. It can also result from aflatoxin or warfarin poisoning.

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Rare hereditary disorder of connective tissue. Affected persons are tall, with long, thin limbs and spiderlike fingers (arachnodactyly). The lens of the eye is dislocated, and many have glaucoma or detached retina. Heart muscle abnormalities and various malfunctions and malformations occur; rupture of the aorta is the most common cause of death. Severity varies; affected individuals may die young or live essentially normal lives. The underlying abnormality cannot be cured, but some of the defects can be surgically corrected.

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Cluster of illnesses in veterans of the Persian Gulf War (1990–91). These illnesses are characterized by variable and nonspecific symptoms such as fatigue, muscle and joint pains, headaches, memory loss, and posttraumatic stress reactions. It is believed to be caused by exposure to chemicals called anticholinesterases, which are found in nerve toxins, insecticides, and prophylactic anti-nerve toxin drugs. The disorder does not appear to be fatal but can be associated with considerable distress and disability.

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or trisomy 21

Congenital disorder caused by an extra chromosome (trisomy) on the chromosome 21 pair. Those with the syndrome may have broad, flat faces; up-slanted eyes, sometimes with epicanthal folds (whence its former name, mongolism); intellectual disability (usually moderate); heart or kidney malformations; and abnormal fingerprint patterns. Many persons with Down syndrome can live and work independently or in a sheltered environment, but they age prematurely and have a short (55-year) life expectancy. The risk of bearing a child with the disorder increases with the mother's age; it can be detected in the fetus by amniocentesis.

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In medicine and psychology, the term syndrome refers to the association of several clinically recognizable features, signs (observed by a physician), symptoms (reported by the patient), phenomena or characteristics that often occur together, so that the presence of one feature alerts the physician to the presence of the others. In recent decades the term has been used outside of medicine to refer to a combination of phenomena seen in association.

In technical medical language, a syndrome refers only to the set of detectable characteristics. A specific disease, condition, or 'disorder may be identified as the underlying cause. Once a physical cause has been identified, the word "syndrome" is sometimes kept in the name of the disease.

The term syndrome derives from the Greek and means literally "run together", as the features do. It is most often used when the reason that the features occur together (the pathophysiology of the syndrome) has not yet been discovered. A familiar syndrome name often continues to be used even after an underlying cause has been found, or when there are a number of different primary causes that all give rise to the same combination of symptoms and signs. Many syndromes are named after the physicians credited with first reporting the association; these are "eponymous" syndromes (see also the list of eponymous diseases, many of which are referred to as "syndromes"). Otherwise, disease features or presumed causes, as well as references to geography, history or poetry, can lend their names to syndromes.

A culture-bound syndrome is a set of symptoms where there is no evidence of an underlying biological cause, and which is only recognized as a "disease" in a particular culture.

Syndromes and associated conditions

The description of a syndrome usually includes a number of essential characteristics, which when concurrent lead to the diagnosis of the condition. Frequently these are classified as a combination of typical major symptoms and signs - essential to the diagnosis - together with minor findings, some or all of which may be absent. A formal description may specify the minimum number of major and minor findings respectively, that are required for the diagnosis.

In contrast to the major and minor findings which are typical of the syndrome, there may be an association with other conditions, meaning that in persons with the specified syndrome these associated conditions occur more frequently than would be expected by chance. While the syndrome and the associated conditions may be statistically related, they do not have a clear cause and effect relationship - i.e. there is likely to be a separate underlying problem or risk factor that explains the association. An example would be Down syndrome which has the associated condition of diabetes mellitus. A knowledge of associated conditions would dictate that they are specifically looked for in the management of the syndrome.

Case studies

One recent case study is Acquired Immune Deficiency Syndrome (AIDS), so named because most syndromal immune deficiencies are either genetically precoded, or secondary to either metabolic disorders or hematological disease.

AIDS was originally termed "Gay Related Immune Disease" (or GRID), a name which was revised as the disease turned out to also affect heterosexuals. Several years passed after the recognition of AIDS before HIV (human immunodeficiency virus) was first described, finally explaining the hitherto mysterious "syndrome".

SARS (severe acute respiratory syndrome) is an even more recent example of a syndrome that was later explained with the identification of a causative coronavirus.

See also

External links

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