OVERVIEW

What is rheumatic fever?

Rheumatic fever is an autoimmune disease caused by the body's immune system attacking its own healthy tissues following a throat infection with group A beta-hemolytic streptococcus.

Rheumatic fever has five typical manifestations: migratory polyarthritis, carditis, subcutaneous nodules, erythema marginatum, and Sydenham's chorea.

Treatment for rheumatic fever includes: eradicating streptococcal infection, reducing damage to joints and the heart, and managing various complications.

Is rheumatic fever a common disease?

Rheumatic fever was relatively common before the mid-20th century. Since then, its incidence has significantly declined worldwide, especially in developed countries.

SYMPTOMS

What are the manifestations before the onset of rheumatic fever?

1–6 weeks before the typical symptoms of rheumatic fever appear, pharyngitis or tonsillitis (indicating streptococcal infection of the throat) often occurs, such as fever, sore throat, cough, and swollen submandibular lymph nodes. Some patients may experience fatigue, weakness, nosebleeds, abdominal pain, or other discomforts.

What are the typical manifestations of rheumatic fever?

Rheumatic fever has five typical manifestations: migratory polyarthritis, carditis, subcutaneous nodules, erythema marginatum, and Sydenham's chorea. These symptoms may appear alone or in combination.

Do all rheumatic fever patients experience fever?

Not necessarily. Fever occurs in 50%–70% of patients, mostly mild to moderate (rarely exceeding 39°C).

What are the manifestations of arthritis caused by rheumatic fever?

Arthritis caused by rheumatic fever mainly presents as "migratory polyarthritis," primarily affecting large joints such as the knees, ankles, elbows, and wrists, with symptoms including redness, swelling, heat, pain, and limited mobility. The arthritis in each joint may resolve on its own after a few days without causing deformity but often recurs. Joint pain usually subsides within 2 weeks and rarely lasts longer than a month.

Arthritis caused by rheumatic fever can also occur in other joints, though less commonly, such as the hips, finger joints, jaw joints, or sternoclavicular joints.

What are the manifestations of carditis caused by rheumatic fever?

Carditis is the most severe manifestation of rheumatic fever, with symptoms including palpitations, shortness of breath after activity, and discomfort in the chest (precordial area). Depending on the affected area, it can be classified as valvulitis, myocarditis, or pericarditis.

Valvulitis is the most common. Repeated episodes of rheumatic fever can gradually lead to chronic valvular heart disease, known as rheumatic heart disease (RHD), primarily manifesting as stenosis and/or regurgitation of the mitral, tricuspid, or aortic valves. Early-stage RHD often has no obvious symptoms, but later stages may present with palpitations, shortness of breath, fatigue, cough, hemoptysis (coughing up blood), and swelling of the lower limbs.

What is erythema marginatum in rheumatic fever?

Erythema marginatum is a type of rash characterized by pale red, ring-shaped patches of varying sizes with pale centers. It typically appears suddenly on the trunk and proximal limbs, fading within hours or a day or two and not recurring afterward. However, in a few patients, the rash may come and go repeatedly for weeks. Erythema marginatum usually appears later after streptococcal infection.

What are subcutaneous nodules in rheumatic fever?

A small number of rheumatic fever patients may develop subcutaneous nodules. These are slightly firm, painless nodules that do not adhere to the skin, measuring 0.1–1 cm in diameter. They appear on extensor surfaces of joints (e.g., elbows, knees, wrists) or on the back of the head and spinal prominences. The overlying skin shows no signs of inflammation. Subcutaneous nodules are often associated with carditis and indicate active rheumatic inflammation.

What is Sydenham's chorea?

Sydenham's chorea primarily affects children aged 4–7 and is relatively uncommon. It involves purposeless, involuntary movements of the whole body or localized muscles, such as facial grimacing, shoulder shrugging, neck twisting, tongue protrusion, or irregular alternating limb movements. Symptoms worsen with excitement and disappear during sleep. Affected children often exhibit emotional instability.

The condition may last 1–3 months, with some cases recurring over 1–2 years. A small number of children may retain varying degrees of sequelae.

What diseases can rheumatic fever cause?

The most common complications of rheumatic fever are infective endocarditis and respiratory infections. Patients with prolonged or recurrent rheumatic fever may develop hypertension, hyperlipidemia, hyperglycemia, or hyperuricemia, often due to long-term glucocorticoid use. Middle-aged and elderly rheumatic fever patients may also have concurrent conditions such as coronary heart disease or myocardial infarction.

CAUSES

What causes rheumatic fever?

• Group A beta-hemolytic streptococcal infection and autoimmune system disorder: Group A beta-hemolytic streptococcal infection can disrupt the human immune system, causing it to attack not only the streptococci but also the body's normal tissues and organs, such as joint synovium, synovial fluid, cartilage, myocardium, and heart valves, leading to organ damage.

• Genetic factors: These may also contribute to the onset of rheumatic fever.

• Bacterial exotoxins: Group A beta-hemolytic streptococci can produce harmful substances like exotoxins, which directly damage human organs.

Is rheumatic fever related to the environment? Does dampness cause rheumatism?

• Rheumatic fever is somewhat related to the environment, but dampness itself does not cause it.

• Overcrowded living conditions, poor nutrition, and lack of medical care facilitate the reproduction and spread of streptococci, increasing the incidence of rheumatic fever. In developing countries, rheumatic fever and rheumatic heart disease remain common and severe. Rural and remote areas in China also report high rates.

• However, in recent years, the incidence among children from relatively affluent families has also risen, with more cases of atypical or subclinical rheumatic fever.

• Damp environments do not directly cause rheumatic fever—the term "rheumatism" can be misleading. The actual causes are the pathogens in such environments and the inadequate healthcare and medical resources, which delay proper treatment.

Is rheumatic fever seasonal?

The disease is more common in winter and spring, during rainy seasons.

What age group is most susceptible to rheumatic fever?

People of any age can develop rheumatic fever, but it most frequently affects children and adolescents aged 5–15.

DIAGNOSIS

What abnormal test results suggest rheumatic fever?

• Evidence of streptococcal infection

• Throat swab culture: Secretions from the throat mucosa are collected and cultured. Some patients may test positive for streptococcus, supporting the diagnosis.

• Antistreptolysin O (ASO): ASO turns positive about 2 weeks after streptococcal infection, with a positive rate of 50%–75%.

• Anti-DNAse B: The positive rate is similar to ASO, and it can be tested alongside ASO.

• Others: Including antistreptokinase (ASK) and antihyaluronidase (AH).

• Elevated inflammatory markers: Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) may increase.

• Immunological tests: IgM, IgG, and complement C3 may rise. Other uncommon specific tests, such as anti-myocardial antibodies, may be positive.

What tests can confirm the presence of carditis?

• Electrocardiogram (ECG): Helps detect arrhythmias.

• Echocardiogram (heart ultrasound): Can identify valvulitis, myocarditis, and pericarditis.

• Myocardial nuclear imaging: Can assess the extent and severity of myocardial involvement.

Doctors will perform these tests based on the patient's condition and hospital resources. These tests can also be used for follow-up evaluations after treatment.

Which diseases resemble rheumatic fever and require differentiation?

• Rheumatoid arthritis: Presents with persistent, symmetrical joint involvement, prominent morning stiffness, positive rheumatoid factor in lab tests, and significant bone/joint damage in imaging.

• Reactive arthritis: History of intestinal or urinary tract infection, mainly affecting lower limb joints, accompanied by enthesitis, low back pain, and HLA-B27 positivity.

• Tuberculous infection-related allergic arthritis: History of tuberculosis infection, positive tuberculin skin test, poor response to NSAIDs (e.g., aspirin), but effective with antituberculosis therapy.

• Subacute infective endocarditis: Features progressive anemia, petechiae, splenomegaly, vascular emboli, and positive bacterial blood cultures.

• Viral myocarditis: Preceded by viral infection symptoms like nasal congestion, runny nose, or tearing, elevated viral antibody titers, and possible severe arrhythmias.

TREATMENT

How to treat rheumatic fever?

• General treatment: Includes rest and keeping warm, especially for patients with carditis, who should rest in bed more and gradually resume activities after the condition stabilizes.

• Eradication of streptococcal infection: Benzathine penicillin is the first choice. Prophylactic medication for recurrent rheumatic fever or rheumatic heart disease depends on the condition. Patients allergic to penicillin can switch to other antibiotics.

• Anti-rheumatic treatment: Nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin, are the first choice for arthritis patients. Low-dose maintenance therapy can be continued after symptom relief, with a treatment course of 4–8 weeks for simple arthritis. Glucocorticoids should be used for carditis. For chorea, sedatives are used alongside anti-rheumatic treatment.

• Complication management: Rheumatic fever patients are prone to lung infections during active disease and may develop complications such as cardiac insufficiency or metabolic disorders, which require timely detection and treatment.

How to treat rheumatic carditis? How long is the treatment course?

Treatment must be conducted under the guidance of a specialist. Glucocorticoids should be used for carditis, with a minimum treatment course of 12 weeks.

If the condition does not improve, glucocorticoid treatment may be extended to 9 months or even longer than 1 year, combined with aspirin, until full recovery. Follow-up visits and cardiac examinations should be scheduled afterward.

What is subclinical rheumatic carditis? How is it treated?

Subclinical rheumatic carditis is rheumatic carditis without obvious symptoms. If there is no history of carditis but recent rheumatic fever, regular monitoring and long-acting penicillin prophylaxis are sufficient, with no special treatment needed. Patients should avoid heavy physical labor while maintaining moderate activity and exercise.

For those with a history of carditis or current rheumatic heart disease, specific treatment measures can be determined based on lab tests, echocardiography, electrocardiograms, and clinical signs. If necessary, a course of anti-rheumatic treatment may be applied.

How to treat rheumatic chorea?

Treatment should be conducted under professional guidance. Patients with chorea should avoid strong light and noise stimulation. Sedatives (e.g., valproic acid) are used alongside anti-rheumatic treatment. Glucocorticoids and immunosuppressants may also be effective. Severe cases may require intravenous immunoglobulin or steroid pulse therapy.

How to treat chronic rheumatic heart disease?

• Balance work and rest, with appropriate exercise and physical activity.

• Actively prevent streptococcal infections and treat rheumatic activity.

• Prevent and manage complications such as infections, arrhythmias, and heart failure.

• Anticoagulation therapy may be considered if necessary.

• Interventional or surgical treatment may be required in severe cases.

Is rheumatic fever prone to recurrence?

Some studies suggest a recurrence rate of about 30%, mostly within 2–5 years.

What is the prognosis of rheumatic fever?

• Generally, earlier diagnosis and treatment lead to better outcomes. About 70% of acute rheumatic fever patients recover within 2–3 months.

• Younger age and more severe initial symptoms correlate with poorer prognosis and higher mortality. Conversely, older age and milder symptoms indicate a better prognosis.

• Patients with complications such as heart failure, infective endocarditis, coronary artery disease, or myocardial infarction have a worse prognosis.

DIET & LIFESTYLE

What should patients with rheumatic fever pay attention to in daily life?

• Improve living conditions and avoid crowded environments (such as college dormitories, military barracks, etc.).

• Maintain a balanced diet to prevent malnutrition.

• Engage in physical exercise to strengthen the body.

• Prevent colds and avoid streptococcal infections; seek medical attention promptly for pharyngitis or tonsillitis.

• Wash hands frequently and use soap or other cleaning agents.

• Cook food thoroughly, reheat leftovers properly, and use clean disposable gloves when handling food.

Does rheumatic fever affect fertility?

Generally, rheumatic fever does not affect fertility. However, if accompanied by other symptoms (such as carditis), especially rheumatic heart disease caused by recurrent rheumatic fever, it may impact fertility, primarily by threatening the safety of both mother and child during pregnancy and childbirth.

PREVENTION

Can rheumatic fever be prevented?

Yes, including primary prevention and secondary prevention.

What is primary prevention for rheumatic fever?

Primary prevention refers to preventing the occurrence of rheumatic fever. It includes:

• Improving socioeconomic conditions, living environments, and nutritional status of residents;

• Engaging in physical exercise to enhance physical fitness;

• Protecting against cold and dampness, and actively preventing streptococcal infections;

• Thoroughly treating streptococcal infections.

What is secondary prevention for rheumatic fever?

Secondary prevention refers to preventing recurrences of rheumatic fever and the development of rheumatic heart disease.

• Benzathine penicillin is the first choice for secondary prevention, with a typical dose of 1.2 million units, administered intramuscularly every 3–4 weeks. The duration and dosage of prevention should be determined based on the patient's age, susceptibility to streptococcal infections, recurrence frequency, and whether the heart is affected.

• For patients with simple arthritis, the prevention duration for children should continue until age 21 and for at least 5 years, while adult patients should receive prevention for at least 5 years.

• For patients with cardiac involvement but no valvular damage, the prevention duration should be at least 10 years, with children receiving prevention until age 21 and for at least 10 years.

• For young patients, those with a predisposition to infection, recurrent rheumatic fever episodes, or a history of carditis or valvular disease, the prevention duration should be extended as much as possible—until age 40 and for at least 10 years, or even lifelong prevention.