RHEUMATIC FEVER
DEFINITION
Rheumatic fever (RF; pronounced roo-MAT-ic FEE-ver) is a disease caused by a group of bacteria known as Group A streptococcus (pronounced STREP-tuh-cac-us). The exact conditions that lead to rheumatic fever are not well understood. However, the condition often follows a case of strep throat that was not treated or not treated correctly. Rheumatic fever can seriously damage the valves of the heart.
DESCRIPTION
Streptococcal infections of the throat and ear are common in young children. These infections can be treated efficiently with antibiotics. When so treated, the infections clear up in about a week. Patients seldom experience complications.
Some streptococcal infections are very mild, however. Children may experience no symptoms, so their parents do not seek medical advice. Also, patients sometimes do not take their full course of medication. They stop taking pills when their symptoms are gone. But streptococcal bacteria may still be present. In either of these cases, complications may develop. One of the most serious complications is rheumatic fever.
Children between the ages of five and fifteen are at greatest risk for RF. The rate of RF in the United States has dropped dramatically. Today, it is rarely seen in this country. It continues to be widespread in developing nations, however. Poverty, overcrowding, and lack of access to proper medical care contribute to the high rate of RF in these areas.
CAUSES
There is still some debate as to how rheumatic fever develops. The most popular theory is that the condition is caused by the body's own immune system. The immune system consists of organs, tissues, cells, and chemicals designed to attack foreign invaders, such as bacteria or viruses. One way the immune system protects the body is with antibodies. Antibodies are chemicals produced to fight off specific foreign agents. There is a specific type of antibody, for example, for every bacterium and virus that can invade the human body.
But the immune system sometimes makes mistakes and produces antibodies that attack the body's own cells. The antibodies kill cells and cause a type of disease known as an autoimmune ("against itself") disorder. Rheumatic fever is thought to be an autoimmune disorder (see autoimmune disorder entry).
SYMPTOMS
In addition to fever, there are five main symptoms of RF. One symptom is arthritis (see arthritis entry). Arthritis is an inflammation of the joints that causes severe pain and swelling. In the case of RF, arthritis produces red, hot, swollen, shiny, and very painful joints of the ankles, knees, elbows, and wrists. The joints may become so sore that even the touch of bed sheets or clothing is too painful to endure.
A second symptom of RF is chorea (pronounced co-REE-uh). Chorea is a disorder of the nervous system. It causes a patient to lose coordination and develop jerky movements of the arms and legs. The patient may also develop emotional problems. He or she may become angry or sad for no reason at all. The chorea that occurs as a result of RF is called Syndenham's chorea. At one time, the condition was known as St. Vitus's Dance.
A third symptom of RF is a rash. The rash consists of pink splotches on the body that are not itchy. The medical term for this rash is erythema marginatum (pronounced air-uh-THEE-muh MAR-gin-ay-tum). Along with the rash there may be small bumps just under the skin. The bumps are hard to the touch but not painful. They occur most commonly over the knee and elbow joints. The bumps constitute the fourth symptom of RF. They are also known as subcutaneous nodules (pronounced sub-CYOO-taynee-us NOD-yools).
Rheumatic Fever: Words to Know
- Antibodies:
- Chemicals produced by the body's immune system to fight off very specific foreign invaders, such as bacteria and viruses.
- Arthritis:
- Inflammation of the joints.
- Autoimmune disorder:
- A medical condition in which the body's immune system mistakes the body's own tissues for foreign invaders and attempts to destroy those tissues.
- Carditis:
- Inflammation of the heart.
- Chorea:
- Involuntary movements that may cause the arms or legs to jerk about uncontrollably.
- Immune system:
- A system of organs, tissues, cells, and chemicals that work together to fight off foreign invaders, such as bacteria and viruses.
- Inflammation:
- The body's response to tissue damage that includes heat, swelling, redness, and pain.
The fifth and most serious symptom of rheumatic fever is called carditis (pronounced car-DIE-tis). The term "carditis" means an inflammation of the heart. About 40 percent to 80 percent of all patients with rheumatic fever develop carditis. It is the most serious complication associated with RF.
One common effect of carditis is damage to the heart valves. The heart valves are flaps of tissue that control the flow of blood in the heart. They ensure that blood always flows in the right direction as it passes through the heart.
If heart valves are damaged, one of two things can happen. First, the flow of blood reverses direction. Second, the valves become so stiff that it is difficult for blood to get through them. Either way, the heart has to work unusually hard to keep blood moving properly. In some cases, the heart has to work so hard that it becomes weakened or fails. The patient develops chronic (long-term) heart disease or dies of a heart attack.
DIAGNOSIS
Diagnosis of rheumatic fever can be difficult because patients may have one, two, or more of the five symptoms listed above. The five symptoms for which a doctor looks include arthritis, chorea, carditis, erythema marginatum, and subcutaneous nodules. Fever is also present. However, fever by itself is not of much use in making a diagnosis. Many kinds of medical disorders have fever as a symptom.
GERHARD DOMAGK
Gerhard Domagk was a German biochemist who was born on October 30, 1895. He earned his medical degree in 1921 and then took a job with a large company, Farbenindustrie. Farbenindustrie manufactured industrial dyes.
Domagk was interested in finding out whether any of the dyes produced by Farbenindustrie had biological effects on animals. In one study, he injected a dye called Prontosil Red into a group of experimental mice. The mice had been given a streptococcus infection. Domagk was amazed to discover that the mice were cured of their disease by the dye.
That discovery might have lead nowhere except for a terrible event in Domagk's life. His daughter Hildegarde pricked herself with a knitting needle and developed a streptococcal infection herself. In desperation, Domagk injected Prontosil Red into his daughter. Again, the dye seemed to work miracles. Hildegarde quickly recovered from the disease.
Shortly after these events, the French chemist Daniele Bovet explained how Prontosil Red works. He showed that only one part of the compound was involved in killing bacteria. That part was a molecule called sulfanilamide. Sulfanilamide was the first of a large group of related compounds, called sulfanamides (or "sulfa drugs") to be used against bacterial infections.
A number of laboratory tests are also used to diagnose RF. For example, a throat smear can be taken to look for the presence of streptococcal bacteria. In a throat smear, a cotton swab is rubbed across the back of the patient's
throat. The material collected on the swab is then placed in a warm, moist environment for twenty-four to seventy-two hours. Any bacteria present in the material begin to grow during that period. If streptococcal bacteria are present, they can be seen with a microscope.
Laboratory tests can also be used to look for antibodies to the streptococcal bacteria. Blood taken from the patient's arm can be treated with chemicals that make these antibodies show up. The presence of the antibodies means that the patient has been infected with the streptococcal bacteria.
An electrocardiogram (ECG; pronounced ih-LEK-tro-KAR-dee-o-gram) can also be used to diagnose RF. An electrocardiogram is a test that measures the electrical activity of the heart. If the heart has been damaged by carditis, its electrical rhythms will be different from those of a healthy heart.
All of these symptoms and tests taken together can provide a diagnosis of rheumatic fever.
TREATMENT
Rheumatic fever is usually treated with penicillin. The patient usually receives a single injection or a ten-day course of pills. Doctors often prescribe a regular dose of penicillin after the symptoms of RF disappear. This program helps prevent the return of RF. Other patients who continue to receive regular doses of penicillin are those individuals who may come into contact with the streptococcal bacterium. This group includes teachers and medical workers, as well as patients with known RF heart disease.
The symptoms of arthritis can be treated with aspirin, acetaminophen (Tylenol), or ibuprofen (Motrin, Advil). These same drugs can be used to treat mild cases of carditis. Aspirin should not be given to children with a fever because it may cause the serious illness Reye's syndrome (see Reye's syndrome entry). More severe cases of carditis are treated with steroid medications. Chorea is treated with a variety of sedatives and tranquilizers that help relax the patient.
PROGNOSIS
RF patients who do not develop carditis have an excellent prognosis. Other symptoms of the disease eventually disappear without complications. Even patients who have mild cases of carditis are likely to experience a full recovery. Severe cases of carditis are another matter. In this case, patients are likely to develop a variety of heart problems that may lead to heart failure. Serious heart problems can often be treated by surgery.
PREVENTION
Rheumatic fever can be prevented with early and proper diagnosis of streptococcal infections of the throat and ears. If antibiotics are given within ten days, the risk of the infection's developing into rheumatic fever is very low.
People who have had rheumatic fever are at risk for contracting the disease again. To prevent the condition from returning, a patient may have to stay on antibiotics for a long time—perhaps for life. People who already have heart damage resulting from RF can prevent further complications. The usual procedure is for the patient to take antibiotics any time he or she might be exposed to the streptococcal bacterium.
FOR MORE INFORMATION
Books
Stoffman, Phyllis. The Family Guide to Preventing and Treating 100 Infectious Diseases. New York: John Wiley and Sons, Inc. 1995.
Web sites
"Rheumatic Fever." Yahoo! Health. [Online] http://dir.yahoo.com/Health/Diseases_and_Conditions/Rheumatic_Fever (accessed on November 5, 1999).
"Rheumatic fever." HealthAnswers Medical Reference Library. [Online] http://www.healthanswers.com/adam/top/view.asp?filename=003940.htm&rdir (accessed on November 5, 1999).