Rheumatic Fever

Rheumatic fever is a serious inflammatory disease that can develop as a complication of an untreated or inadequately treated strep throat infection. It occurs when your body's immune system, fighting the strep bacteria, mistakenly attacks healthy tissues, most commonly affecting the heart, joints, brain, and skin. Early diagnosis and treatment of strep throat are crucial to prevent rheumatic fever.

What is Rheumatic Fever?

Rheumatic fever is an inflammatory disease that can develop after a bacterial infection, most often strep throat, is not fully treated. It is not an infection itself but rather an autoimmune reaction where your body's immune system attacks its own tissues. This condition can affect various parts of the body, including the heart, joints, brain, and skin, potentially leading to serious long-term health problems.

Rheumatic fever is a serious complication of an infection caused by Group A Streptococcus (GAS) bacteria, commonly known as strep throat or scarlet fever. While strep throat is a common and usually mild infection, if it's left untreated or not fully treated with antibiotics, about 1 in 100 children (1%) may develop rheumatic fever. This condition is not contagious; you cannot catch rheumatic fever from someone else. Instead, rheumatic fever is an autoimmune response. This means that your body's immune system, which normally fights off infections, gets confused. It creates antibodies to fight the strep bacteria, but these antibodies sometimes also attack similar-looking proteins found in your own body's tissues. This mistaken attack leads to inflammation and damage in different organs. The most concerning complication of rheumatic fever is its potential to cause permanent heart damage, known as rheumatic heart disease (RHD). This damage can affect the heart valves, making it harder for the heart to pump blood effectively. While rheumatic fever can be severe, it is largely preventable with prompt and complete treatment of strep throat.

Symptoms

The symptoms of rheumatic fever can vary widely among individuals and may not appear until two to four weeks after the initial strep throat infection has cleared. Common signs include fever, painful and swollen joints that may move from one joint to another, and sometimes a distinctive rash. Heart inflammation can occur, though it might not cause noticeable symptoms initially.

Symptoms of rheumatic fever often appear suddenly and can range from mild to severe. One of the most common symptoms is arthritis, which involves painful, swollen, and tender joints. This pain often "migrates," meaning it moves from one joint to another, typically affecting the knees, ankles, elbows, and wrists. Other common symptoms include a fever, which can be high, and fatigue. Some people may develop a specific type of skin rash called erythema marginatum, which appears as pink or red rings with clear centers, often on the trunk or upper arms and legs. Small, firm, painless lumps (nodules) can also form under the skin, usually over bony areas like elbows or knees. In some cases, rheumatic fever can affect the brain, leading to involuntary, jerky movements known as Sydenham chorea. These movements can affect the hands, feet, and face, and may be accompanied by emotional changes. The most serious symptoms involve the heart (carditis), which can cause chest pain, shortness of breath, or a rapid heart rate, though heart inflammation can sometimes be present without obvious symptoms.

Causes & risk factors

Rheumatic fever is caused by an abnormal immune response to an untreated or inadequately treated infection with Group A Streptococcus (strep throat). It is not the bacteria itself that causes the disease, but rather the body's immune system reacting mistakenly. Risk factors include age, genetics, and environmental conditions that increase the likelihood of strep throat transmission.

The primary cause of rheumatic fever is an infection with Group A Streptococcus (GAS) bacteria, specifically strep throat or scarlet fever. When these infections are not treated with antibiotics, or if the antibiotic course is not completed, the body's immune system can launch an attack that mistakenly targets its own tissues. This autoimmune reaction is what leads to the inflammation and damage characteristic of rheumatic fever. Certain factors can increase a person's risk of developing rheumatic fever. Age is a significant factor, as it most commonly affects children between 5 and 15 years old, though it can occur in younger children and adults. Genetic predisposition also plays a role; some people may be more genetically susceptible to developing the condition after a strep infection. Environmental factors are also important. Overcrowding in homes, poor sanitation, and limited access to healthcare can increase the risk of strep throat infections spreading rapidly within a community. These conditions make it more likely that strep infections will go untreated or be treated inadequately, thereby raising the risk of rheumatic fever.

How it's diagnosed

Diagnosing rheumatic fever involves a thorough physical examination, reviewing your medical history, and performing various tests to look for evidence of a recent strep infection and inflammation. There isn't a single test for rheumatic fever; instead, doctors use a set of criteria, including symptoms and test results, to make a diagnosis. Heart tests may also be used to check for cardiac involvement.

When a doctor suspects rheumatic fever, they will first conduct a physical exam and ask about your symptoms and recent medical history, especially if you've had a sore throat. They will look for signs like joint swelling, skin rashes, and listen to your heart for murmurs or other abnormalities that could indicate heart inflammation. Blood tests are crucial for diagnosis. These include tests to detect a recent strep infection, such as an antistreptolysin O (ASO) titer or anti-DNase B test, which measure antibodies your body made against the strep bacteria. Tests for inflammation, like the erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), will also be done, as these levels are typically elevated during active rheumatic fever. To assess heart involvement, an electrocardiogram (ECG) may be performed to check the electrical activity of your heart, and an echocardiogram (echo) can provide detailed images of your heart's structure and function, including any damage to the heart valves. Doctors use a set of guidelines called the modified Jones criteria, which combine clinical symptoms with laboratory and heart test results, to confirm a diagnosis of rheumatic fever.

Treatment options

Treatment for rheumatic fever focuses on eliminating any remaining strep bacteria, reducing inflammation and symptoms, and preventing future recurrences. This typically involves antibiotics to eradicate the infection and anti-inflammatory medications to manage pain and swelling. Long-term antibiotic therapy is often prescribed to prevent future strep infections and protect the heart.

The first step in treating rheumatic fever is to eliminate any lingering Group A Streptococcus bacteria from your body. This is done with antibiotics, usually penicillin, given as a shot or in pill form. Even if a strep test is negative, antibiotics are often given if there's strong evidence of a recent infection, to ensure the bacteria are completely gone. To manage the inflammation and symptoms, doctors prescribe anti-inflammatory medications. Aspirin is commonly used to reduce fever, pain, and swelling in the joints. For more severe inflammation, especially if the heart is affected, corticosteroids like prednisone may be used. These medications help to calm the immune response and reduce damage to tissues. Preventing future strep infections is critical because each new strep infection can trigger another episode of rheumatic fever, potentially causing more heart damage. For this reason, people who have had rheumatic fever often need long-term, regular antibiotic treatments, sometimes for many years or even for life, especially if they have developed rheumatic heart disease. This preventive treatment is called prophylaxis.

Recovery & outlook

The recovery from rheumatic fever varies greatly depending on which parts of the body were affected and the severity of the inflammation. While joint pain and other acute symptoms usually resolve completely, the most serious long-term concern is potential permanent damage to the heart valves, known as rheumatic heart disease. Lifelong follow-up and preventive antibiotics are often necessary to manage the condition and prevent recurrence.

Most acute symptoms of rheumatic fever, such as joint pain, fever, and rash, usually resolve within a few weeks to months with appropriate treatment. However, the long-term outlook is primarily determined by whether the heart was affected during the illness. If the heart was not involved, or if the inflammation was mild, a full recovery without lasting damage is possible. If the heart was inflamed (carditis), there is a risk of developing rheumatic heart disease (RHD). RHD is a serious condition where the heart valves become scarred, narrowed, or leaky, making it harder for the heart to pump blood. This damage can be permanent and may lead to heart failure, stroke, or other complications later in life. The severity of RHD can range from mild to severe, sometimes requiring surgery to repair or replace damaged valves. Because subsequent strep infections can trigger new episodes of rheumatic fever and worsen heart damage, long-term preventive antibiotics are crucial. People with a history of rheumatic fever, especially those with heart involvement, will need ongoing medical care, including regular check-ups with a cardiologist (heart specialist), to monitor their heart health and ensure continued prevention of strep infections.

When to see a doctor

You should see a doctor if you or your child develops a sore throat, especially if it's accompanied by fever, difficulty swallowing, or a rash. Prompt medical attention for strep throat is essential to prevent rheumatic fever. If you have recently had strep throat and then develop new symptoms like joint pain, fever, or unusual movements, seek medical advice immediately.

It is very important to see a doctor if you suspect you or your child has strep throat. Symptoms of strep throat often include a sudden sore throat, pain when swallowing, fever, and sometimes a rash (scarlet fever). Getting a diagnosis and starting antibiotics quickly can prevent rheumatic fever from developing. If you have been diagnosed with strep throat, it is crucial to complete the entire course of antibiotics as prescribed by your doctor, even if you start feeling better. Stopping antibiotics early can allow some bacteria to survive and potentially trigger rheumatic fever. If you or your child has recently had strep throat and then develops new symptoms such as joint pain that moves from one joint to another, a new fever, a skin rash, or unusual, jerky body movements, you should see a doctor right away. These could be signs of rheumatic fever and require immediate medical evaluation.

Frequently asked questions

Can adults get rheumatic fever?

Yes, while rheumatic fever most commonly affects children between the ages of 5 and 15, adults can also develop the condition. It occurs when an untreated or inadequately treated strep throat infection triggers an autoimmune reaction, regardless of age. However, it is less common in adults than in children.

Is rheumatic fever contagious?

No, rheumatic fever itself is not contagious. It is an autoimmune disease that develops in response to a strep throat infection. The strep throat infection, however, is highly contagious and can spread from person to person through respiratory droplets when an infected person coughs or sneezes.

How long does it take for rheumatic fever symptoms to appear after strep throat?

The symptoms of rheumatic fever typically appear about two to four weeks after the initial strep throat infection. This delay occurs because the body needs time to develop the autoimmune response that leads to the inflammation and symptoms of rheumatic fever.

Can rheumatic fever be cured?

The acute symptoms of rheumatic fever, such as joint pain and fever, can usually be treated and resolved. However, if the heart has been damaged, this condition, known as rheumatic heart disease, can be permanent. Long-term antibiotic treatment is often necessary to prevent future episodes and further heart damage.

What is rheumatic heart disease?

Rheumatic heart disease (RHD) is a serious, long-term complication of rheumatic fever. It occurs when the inflammation caused by rheumatic fever permanently damages the heart valves. This damage can lead to heart problems like valve narrowing or leaking, which can impair the heart's ability to pump blood effectively and may require surgery.

How can I prevent rheumatic fever?

The most effective way to prevent rheumatic fever is to promptly diagnose and fully treat strep throat infections with antibiotics. If you or your child develops a sore throat, especially with fever, see a doctor for a strep test. If diagnosed with strep throat, complete the entire course of antibiotics as prescribed, even if symptoms improve quickly.

Sources

• MedlinePlus — Rheumatic Fever
• Mayo Clinic — Rheumatic Fever
• Cochrane Library — Rheumatic Fever