Rheumatic Fever
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 throat infection, (strep throat), it is not an infection. Rather, it is an inflammatory reaction to the infection. The parts of the body most commonly affected by the inflammation include the joints, heart, skin, and nervous system. Most people with rheumatic fever recover, but the heart is permanently damaged in a small percentage of people.
Rheumatic fever rarely develops before age 3 or after age 40 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. About half of the children who have had rheumatic fever will develop it again after another streptococcal throat infection if it is not treated. 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
Symptoms of rheumatic fever vary greatly, depending on which parts of the body become inflamed. Typically, symptoms begin several weeks after the disappearance of throat symptoms. The most common symptoms of rheumatic fever are joint pain, fever, chest pain or palpitations caused by heart inflammation (carditis), jerky uncontrollable movements (Sydenham's chorea), a rash, and small bumps (nodules) under the skin. A child may have one symptom or several.
Joints: 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. Rheumatic fever does not cause long-term joint damage.
Heart: Some 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, nonproductive 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 with 30% who had mild inflammation and 70% who had 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. 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 and atrial fibrillation, an abnormal heart rhythm.
Skin: 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 or joint inflammation, small, hard nodules may form under the skin, typically near the affected joints. The nodules are usually painless.
Nervous System: Jerky uncontrollable movements (Sydenham's chorea) may begin gradually in children with rheumatic fever, but usually only after all other symptoms have subsided. A month may go by before the jerky 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. They often begin in the hands and spread to the feet and face. Facial grimacing is common. In mild cases, children may seem clumsy and may have slight difficulties in dressing and eating. In severe cases, children may have to be protected from injuring themselves with their 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. How long this preventive treatment should be continued is unclear. It depends on the severity of the disease and is usually continued at least until adulthood.
Some doctors recommend that it should be continued for life in certain people, such as those who have lasting heart damage, who had chorea, or who have close contact with young children (because the children may carry streptococcal bacteria, which could reinfect such people).
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