Rheumatic fever is an inflammatory disorder that can affect various body tissues, including the heart, joints, skin, and brain. This inflammatory response, if left untreated, can lead to permanent heart damage, a condition known as rheumatic heart disease. Understanding the progression from an initial infection to these health issues is important for effective prevention and management.
Understanding Rheumatic Fever
Rheumatic fever is an autoimmune reaction that develops two to four weeks following an infection with Group A Streptococcus (GAS) bacteria, known as strep throat. This occurs when the body’s immune system, in its effort to fight the strep infection, mistakenly attacks its own healthy tissues due to similarities between bacterial antigens and human proteins, a phenomenon called molecular mimicry. While strep throat is contagious, rheumatic fever itself is not, as it is an immune response rather than an infection.
The disease primarily affects children between the ages of 5 and 15, though it can occur at any age. It can manifest with various symptoms affecting joints, skin, and the nervous system.
How Rheumatic Fever Leads to Heart Disease
Acute rheumatic fever can cause inflammation within the heart, known as carditis, which is the most significant manifestation and occurs in approximately 50% of patients. This inflammation can affect any layer of the heart, but it disproportionately targets the heart valves. The immune system’s attack on the heart tissue, particularly the valves, leads to inflammation and subsequent scarring over time. This damage is progressive, meaning it can worsen with repeated episodes of rheumatic fever or even after a single severe instance.
The mitral valve, which controls blood flow between the upper left and lower left chambers of the heart, is most frequently affected, although the aortic valve can also be damaged. Scarring and thickening of the valve leaflets can lead to two primary issues: stenosis, where the valve narrows and obstructs blood flow, or regurgitation, where the valve fails to close properly, causing blood to leak backward. This impaired blood flow forces the heart to work harder, which can result in long-term consequences such as heart failure, where the heart cannot pump blood effectively. Other complications include arrhythmias, such as atrial fibrillation (an irregular heartbeat), and an increased risk of infective endocarditis, an infection of the heart’s inner lining.
Identifying Symptoms
Symptoms of acute rheumatic fever typically appear one to six weeks after a strep infection and can vary. These may include:
Fever, often above 100.4°F (38°C).
Joint pain or swelling that might move from one joint to another, often affecting knees and ankles.
A characteristic non-itchy, red, lattice-like rash known as erythema marginatum, often appearing on the chest, back, and belly.
Small, painless lumps under the skin, called subcutaneous nodules, typically over bony areas.
Sydenham’s chorea, marked by involuntary, jerky movements, particularly of the face and hands, sometimes with emotional instability.
Shortness of breath and chest discomfort, indicating heart involvement.
Symptoms of chronic rheumatic heart disease, which result from permanent heart damage, may not become apparent until years or even decades after the initial rheumatic fever episode. These often relate to the heart’s reduced ability to pump blood efficiently. Common symptoms include shortness of breath, particularly during activity or when lying down, persistent fatigue, and swelling in the legs, ankles, or abdomen. Chest pain and heart palpitations, sensations of a rapid or irregular heartbeat, can also indicate valve dysfunction. Prompt medical evaluation is warranted to assess heart health.
Diagnosis and Management
Diagnosing rheumatic fever involves a thorough physical examination and consideration of the patient’s medical history, particularly any recent strep infections. There is no single test for rheumatic fever, so doctors rely on a set of criteria, such as the modified Jones Criteria, which consider major and minor manifestations alongside evidence of a recent strep infection. Blood tests can detect signs of inflammation, such as elevated C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), and antibodies to strep bacteria, like an ASO titer. To assess heart involvement, an electrocardiogram (ECG) can check for abnormal heart rhythms, and an echocardiogram, an ultrasound of the heart, provides detailed images of heart chambers and valve function.
Treatment for acute rheumatic fever focuses on eliminating the remaining strep infection and managing inflammation. Antibiotics, such as penicillin, are administered to eradicate the Group A Streptococcus bacteria. Anti-inflammatory medications, including aspirin or corticosteroids, are used to reduce inflammation and alleviate symptoms like joint pain and fever. For rheumatic heart disease, management often involves regular monitoring by a cardiologist to track the extent of valve damage. Medications may be prescribed to manage symptoms of heart failure or irregular heartbeats, and in cases of severe valve damage, surgical interventions like valve repair or replacement may become necessary to restore proper heart function.
Preventing Future Complications
Preventing rheumatic fever begins with prompt and complete treatment of strep throat infections. If a strep infection is diagnosed, a full course of antibiotics, typically penicillin, is important to eradicate the bacteria and prevent the immune response that can lead to rheumatic fever. This primary prevention strategy is highly effective in stopping the initial disease.
For individuals who have already experienced rheumatic fever, secondary prevention is necessary to prevent recurrent episodes, which can cause further damage to the heart valves. This involves long-term antibiotic prophylaxis, often with regular injections of benzathine penicillin G every three to four weeks for many years, sometimes even for life, especially if heart damage is present. Public health initiatives also play a role by improving living conditions and access to healthcare, which helps reduce the spread of Group A Streptococcus infections and ensures timely treatment.