Rheumatic Fever
Rheumatic fever is inflammation of the body's organ systems, especially the joints and the heart, resulting from a complication of streptococcal infection of the throat.
Although rheumatic fever follows a streptococcal infection, it is not an infection. Rather, it is an inflammatory reaction to the infection. Most people with rheumatic fever recover, but the heart is permanently damaged in a small percentage of people.
In the United States, rheumatic fever rarely develops before age 4 or after age 18 and is much less common than in developing countries, probably because antibiotics are widely used to treat streptococcal infections at an early stage. However, the incidence of rheumatic fever sometimes rises and falls in a particular area for unknown reasons. Overcrowded living conditions seem to increase the risk of rheumatic fever, and heredity seems to play a part. In the United States, a child who has a streptococcal throat infection but is not treated has only a 0.4 to 1% chance of developing rheumatic fever. About half of the children who previously had rheumatic fever will develop it again with another streptococcal throat infection. Rheumatic fever follows streptococcal infections of the throat but not those of the skin (impetigo) or other areas of the body; the reasons are not known.
Symptoms
Rheumatic fever affects many parts of the body, such as the joints, heart, and skin. Symptoms of rheumatic fever vary greatly, depending on which parts of the body become inflamed. Typically, symptoms begin several weeks after the disappearance of strep throat. The most common symptoms of rheumatic fever are joint pain, fever, chest pain or palpitations caused by heart inflammation, jerky uncontrollable movements (Sydenham's chorea), a rash, and small bumps (nodules) under the skin. A child may have one symptom or several.
Joint pain and fever are the most common first symptoms. One or several joints suddenly become painful and feel tender when touched. They may also be red, hot, and swollen and may contain fluid. Ankles, knees, elbows, and wrists are commonly affected; the shoulders, hips, and small joints of the hands and feet also may be affected. As pain in one joint improves, pain in another starts (migratory pain). Joint pains may be mild or severe, and typically last 2 to 4 weeks. Long-term joint damage from rheumatic fever does not develop.
Sometimes, children with heart inflammation have no symptoms, and the past inflammation is recognized years later when heart damage is discovered. Some children feel their heart beating rapidly. Others have chest pain caused by inflammation of the sac around the heart. Heart failure may develop, causing the child to feel tired and short of breath, with nausea, vomiting, stomachache, or a hacking cough.
Heart inflammation disappears gradually, usually within 5 months. However, it may permanently damage the heart valves, resulting in rheumatic heart disease. The likelihood of rheumatic heart disease varies with the severity of the initial heart inflammation. About 1% of people who had no heart inflammation develop rheumatic heart disease, compared to 30% with mild inflammation and 70% with severe inflammation. In rheumatic heart disease, the valve between the left atrium and ventricle (mitral valve) is most commonly damaged. The valve may become leaky (mitral valve regurgitation), abnormally narrow (mitral valve stenosis), or both (see Section 3, Chapter 28 and Section 3, Chapter 28). Valve damage causes the characteristic heart murmurs that enable a doctor to diagnose rheumatic fever. Later in life, usually in middle age, the valve damage may cause heart failure (see Section 3, Chapter 25) and atrial fibrillation, an abnormal heart rhythm (see Section 3, Chapter 27).
A flat painless rash with a wavy edge (erythema marginatum) may appear as the other symptoms subside. It lasts for only a short time, sometimes less than a day. In children with heart inflammation, small, hard nodules may form under the skin. The nodules are usually painless and disappear without treatment.
Jerky uncontrollable movements (Sydenham's chorea) may begin gradually in children with rheumatic fever, but usually only after all other symptoms have improved. A month may go by before the movements become so intense that the child is taken to a doctor. By then, the child typically has rapid, purposeless, sporadic movements that disappear during sleep. The movements may involve any muscle except those of the eyes. Facial grimacing is common. In mild cases, the child may seem clumsy and may have slight difficulties in dressing and eating. In extreme cases, the child may have to be protected from injuring himself with his flailing arms or legs. The chorea lasts between 4 and 8 months.
Diagnosis
A doctor bases the diagnosis of rheumatic fever mainly on the characteristic combination of symptoms. Blood tests showing high levels of antibodies to streptococci may be helpful, but low levels of these antibodies are present in many children who do not have rheumatic fever. Abnormal heart rhythms caused by heart inflammation can be seen on an electrocardiogram (ECG--a recording of the heart's electrical activity). An echocardiogram (an image of structures in the heart produced by ultrasound waves) may be used to diagnose abnormalities of the heart valves.
Prevention and Treatment
The best way to prevent rheumatic fever is with prompt and complete antibiotic treatment of any streptococcal throat infection. In addition, children who have had rheumatic fever should be given penicillin by mouth every day, or by monthly injections into the muscle, to help prevent another streptococcal infection. This preventive treatment should be continued until adulthood, and some doctors feel that it should be continued for life.
Treatment of rheumatic fever has three goals: curing any residual streptococcal infection; reducing inflammation, particularly in the joints and heart; and limiting physical activity that might aggravate the inflamed structures.
Doctors give children with rheumatic fever an injection of a long-acting penicillin to eliminate any remaining infection. Aspirin is given in high doses to reduce inflammation and pain, particularly if inflammation has reached the joints and heart. It is unclear whether other nonsteroidal anti-inflammatory drugs (NSAIDs) are as effective as aspirin. Analgesics, such as codeine, are sometimes used in addition to aspirin. If heart inflammation is severe, corticosteroids such as prednisone may be given to further reduce inflammation.
Bed rest may help by avoiding stress on the painful, inflamed joints. When the heart is inflamed, more rest is generally suggested.
If the heart valves become damaged, the risk of developing a valve infection (endocarditis) remains throughout life (see Section 3, Chapter 29). Those who have heart damage must always take an antibiotic before undergoing any surgery, including dental surgery, even in adulthood.
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