Syndrome

• ALSO KNOWN AS: Condition, disease, disorder
• ANATOMY OR SYSTEM AFFECTED: All

DEFINITION: A group or pattern of recognizable symptoms or conditions that occur together and indicate a specific disease, psychological disorder, or other abnormal condition

Causes and Symptoms

A syndrome is a collection of symptoms that characterize a disorder. For example, metabolic syndrome is the name given to a group of symptoms that warn of potential heart disease, stroke, or diabetes. The symptoms of metabolic syndrome are obesity, high blood pressure, low levels of insulin, and high cholesterol.

Syndromes are generally classified either by cause or by the body system affected. Etiological categories include genetic or congenital syndromes, environmental syndromes from toxins or pollutants, infectious syndromes caused by bacteria, viruses, fungi, or parasites, iatrogenic syndromes resulting from medical treatment, neoplastic syndromes associated with benign or malignant tumors, and idiopathic or medically unexplained syndromes. Syndromes may also be grouped by the organ system primarily involved, such as cardiovascular, pulmonary, gastrointestinal, renal or urogenital, endocrine or metabolic, neurological, musculoskeletal, or psychiatric.

The causes of syndromes vary. Some come from a single, clear source. For example, toxic shock syndrome is caused by the bacterium Staphylococcus aureus. The bacterium enters the body through wounds from injuries or surgical incisions. It also breeds in superabsorbent tampons and contraceptive sponges. Symptoms of this syndrome include fever, headache, vomiting, diarrhea, and muscle aches.

Some syndromes result from any one of an array of causes. Fanconi syndrome, for instance, activates the release of certain substances from the kidney into the urine instead of the bloodstream. It can be caused by genetic defects, inherited diseases, exposure to heavy metals, a kidney transplant, or any number of medicines or diseases that damage the kidneys.

Other syndromes, such as carpal tunnel syndrome, arise from a combination of causes. This syndrome stems from increased pressure on certain nerves and tendons in the carpal tunnel in the wrist. Most people prone to carpal tunnel syndrome are born with a comparatively small carpal tunnel. This condition is complicated by injury to the wrist, an overactive pituitary gland, an underactive thyroid, rheumatoid arthritis, repeated use of vibrating hand tools, or overuse of the hands for activities such as typing.

The causes of some syndromes remain uncertain. For example, Reye's syndrome is a rapidly appearing, deadly disorder that affects all body organs, most seriously the brain and liver. It attacks adults but is primarily a children’s disease. Symptoms include personality changes, seizures, and loss of consciousness. There is no cure. The cause is unknown, but there seems to be a link to the use of aspirin taken for a previous viral disease.

Restless legs syndrome is the nighttime twitching of the legs that often leads to insomnia. The cause is unknown, but there seems to be some connection to a family history of the disorder. Also associated with this syndrome are anemia, diabetes, kidney failure, and certain prescription and nonprescription medicines.

Just as the causes vary, so too do the number and severity of symptoms, depending on the syndrome. Barrett’s esophagus, for example, is a condition in which the esophagus (the tube that carries food to the stomach) develops new cells similar to those found in the intestines. Symptoms are nonexistent, and the cause is unknown. It can, however, lead to a deadly type of esophageal cancer.

The symptoms of premenstrual syndrome vary widely in number and severity from woman to woman. Some women experience few symptoms; others need several days of bed rest. Symptoms include irritability, headache, backache, weight gain, swelling or tenderness of the breasts, depression, fatigue, and loss of sex drive.

Some fifty different symptoms, or characteristics, are associated with Down syndrome. Characteristics include intellectual disabilities; short stature; slow physical growth; weak muscles; short, stocky arms and legs; a wide space between the big toe and second toe; small, low-set ears; a narrow roof of the mouth; crooked teeth and other dental problems; heart defects; an underactive thyroid; and hearing problems. So many symptoms require a lifetime of care.

Asperger syndrome produces no symptoms that require medical attention, but people with this autism spectrum disorder display abnormal behaviors and have limited social skills that can bring on unwanted consequences, such as being shunned by others. Some people with this syndrome seem “normal” most of the time. Others just seem odd or different from other people, quieter and disinterested. Still others exhibit somewhat bizarre, or at least socially unacceptable, behaviors, such as inflexible routines, a narrow but intense focus of interests, an inability to empathize with other people, and difficulty understanding some types of humor, especially teasing and sarcasm. Yet they are often above average in intelligence and do no more harm than so-called normal people. The odd behaviors lead people to think that Asperger syndrome is a mental disorder. In fact, it is a type of autism, a developmental disability that affects how the brain processes information. The cause is unknown.

Treatment and Therapy

Treatment of a syndrome depends on the underlying causes and the severity and number of symptoms. Because syndromes run the full range of medical problems, treatments run the full range as well. Drugs, surgery, physical therapy, diet and lifestyle changes, alternative medicine, and psychotherapy are all used to treat syndromes.

Perspective and Prospects

Both Western and Eastern medical practitioners have long recognized that a set of symptoms can describe an abnormal condition. Syndromes are researched, diagnosed, and treated no differently than individual diseases are.

Bibliography

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Kirmayer, Laurence, et al. “Explaining Medically Unexplained Symptoms.” Canadian Journal of Psychiatry, vol. 49, no. 10, Oct. 2004, pp. 663–72.

McConnaughy, Rozalynd. “Asperger Syndrome: Living Outside the Bell Curve.” Journal of the Medical Library Association, vol. 93, no. 1, Jan. 2005, pp. 139–40.

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Rice, Shirley. “Reye’s Syndrome Isn’t Just Child’s Play.” Nursing, vol. 33, no. 9, Sept. 2003, pp. 32hn1–32hn4.

“What Is the Difference between a Syndrome and a Disorder?” Igenomix, 20 Sept. 2020, www.igenomix.net/blog/what-is-the-difference-between-a-syndrome-and-a-disorder/. Accessed 18 Sept. 2025.