Rheumatic fever is an inflammatory disease that can develop as a complication of inadequately treated strep throat or scarlet fever. Strep throat and scarlet fever are caused by an infection with streptococcus bacteria.
Rheumatic fever is most common in 5- to 15-year-old children, though it can develop in younger children and adults. Although strep throat is common, rheumatic fever is rare in the United States and other developed countries. However, rheumatic fever remains common in many developing nations.
Rheumatic fever can cause permanent damage to the heart, including damaged heart valves and heart failure. Treatments can reduce damage from inflammation, lessen pain and other symptoms, and prevent the recurrence of rheumatic fever.
Rheumatic fever symptoms vary. You can have few symptoms or several, and symptoms can change during the course of the disease. The onset of rheumatic fever usually occurs about two to four weeks after a strep throat infection.
Rheumatic fever signs and symptoms — which result from inflammation in the heart, joints, skin or central nervous system — can include:
- Painful and tender joints — most often in the knees, ankles, elbows and wrists
- Pain in one joint that migrates to another joint
- Red, hot or swollen joints
- Small, painless bumps (nodules) beneath the skin
- Chest pain
- Heart murmur
- Flat or slightly raised, painless rash with a ragged edge (erythema marginatum)
- Jerky, uncontrollable body movements (Sydenham chorea, or St. Vitus' dance) — most often in the hands, feet and face
- Outbursts of unusual behavior, such as crying or inappropriate laughing, that accompanies Sydenham chorea
When to see a doctor
Have your child see a doctor for signs or symptoms of strep throat. Proper treatment of strep can prevent rheumatic fever. Also, have your child see a doctor if he or she shows other indications of rheumatic fever.
Rheumatic fever can occur after an infection of the throat with a bacterium called group A streptococcus. Group A streptococcus infections of the throat cause strep throat or, less commonly, scarlet fever. Group A streptococcus infections of the skin or other parts of the body rarely trigger rheumatic fever.
The link between strep infection and rheumatic fever isn't clear, but it appears that the bacterium tricks the immune system. The strep bacterium contains a protein similar to one found in certain tissues of the body. So immune system cells that would normally target the bacterium may treat the body's own tissues as if they were infectious agents — particularly tissues of the heart, joints, skin and central nervous system. This immune system reaction results in inflammation.
If your child receives prompt treatment with an antibiotic to eliminate strep bacteria and takes all medication as prescribed, there's little chance of developing rheumatic fever. If your child has one or more episodes of strep throat or scarlet fever that aren't treated or not treated completely, he or she might develop rheumatic fever.
Factors that can increase the risk of rheumatic fever include:
- Family history. Some people carry a gene or genes that might make them more likely to develop rheumatic fever.
- Type of strep bacteria. Certain strains of strep bacteria are more likely to contribute to rheumatic fever than are other strains.
- Environmental factors. A greater risk of rheumatic fever is associated with overcrowding, poor sanitation and other conditions that can easily result in the rapid transmission or multiple exposures to strep bacteria.
Inflammation caused by rheumatic fever can last a few weeks to several months. In some cases, the inflammation causes long-term complications.
Rheumatic heart disease is permanent damage to the heart caused by rheumatic fever. It usually occurs 10 to 20 years after the original illness. Problems are most common with the valve between the two left chambers of the heart (mitral valve), but the other valves can be affected. The damage can result in:
- Valve stenosis. This narrowing of the valve decreases blood flow.
- Valve regurgitation. This leak in the valve allows blood to flow in the wrong direction.
- Damage to heart muscle. The inflammation associated with rheumatic fever can weaken the heart muscle, affecting its ability to pump.
Damage to the mitral valve, other heart valves or other heart tissues can cause problems with the heart later in life. Resulting conditions can include:
- An irregular and chaotic beating of the upper chambers of the heart (atrial fibrillation)
- An inability of the heart to pump enough blood to the body (heart failure)
The only way to prevent rheumatic fever is to treat strep throat infections or scarlet fever promptly with a full course of appropriate antibiotics.
Although there's no single test for rheumatic fever, diagnosis is based on medical history, physical exam and certain test results.
If your child was already diagnosed with a strep infection, your doctor might not order additional tests for the bacterium. If your doctor orders a test, it will most likely be a blood test that can detect antibodies to the strep bacterium circulating in the blood. The actual bacterium might no longer be detectable in your child's throat tissues or blood.
Your doctor also is likely to check for inflammation in your child's blood by measuring C-reactive protein and the erythrocyte sedimentation rate.
Electrocardiogram (ECG or EKG)
This test — also called an ECG or EKG — records electrical signals as they travel through your child's heart. Your doctor can look for patterns among these signals that indicate inflammation of the heart or poor heart function.
Using sound waves to produce live-action images of the heart, this test can enable your doctor to detect heart abnormalities.
The goals of treatment for rheumatic fever are to destroy remaining group A streptococcal bacteria, relieve symptoms, control inflammation and prevent recurrences.
Antibiotics. Your child's doctor will prescribe penicillin or another antibiotic to eliminate remaining strep bacteria.
After your child has completed the full antibiotic treatment, your doctor will begin another course of antibiotics to prevent recurrence of rheumatic fever. Preventive treatment will likely continue through age 21 or until your child completes a minimum five-year course of treatment, whichever is longer.
People who have had heart inflammation during rheumatic fever might be advised to take the preventive antibiotic treatment for 10 years or longer.
- Anti-inflammatory treatment. Your doctor will prescribe a pain reliever, such as aspirin or naproxen (Naprosyn), to reduce inflammation, fever and pain. If symptoms are severe or your child isn't responding to the anti-inflammatory drugs, your doctor might prescribe a corticosteroid.
- Anticonvulsant medications. For severe involuntary movements caused by Sydenham chorea, your doctor might prescribe an anticonvulsant, such as valproic acid (Depakene) or carbamazepine (Carbatrol, Tegretol, others).
Discuss with your doctor what type of follow-up and long-term care your child will need. Heart damage from rheumatic fever might not show up for years. When your child grows up, he or she needs to include the information in his or her medical history and get regular heart exams.
Your doctor might recommend bed rest for your child and ask you to restrict his or her activities until inflammation, pain and other symptoms have improved. If inflammation is in heart tissues, your child might need strict bed rest for a few weeks to a few months, depending on the degree of inflammation.
If your child has signs or symptoms of rheumatic fever, you're likely to start by seeing your child's pediatrician. However, the doctor might refer you to a heart specialist (pediatric cardiologist) for some diagnostic tests.
Here's some information to help you get ready for the appointment.
What you can do
Before the appointment, make a list of:
- Your child's symptoms, including any that seem unrelated to your reason for scheduling the appointment and any that have recently been resolved
- Recent illnesses your child has had
- All medications, vitamins or other supplements, your child takes or has recently taken
- Questions to ask your doctor
Take a family member or friend along, if possible, to help you remember the information you're given. For rheumatic fever, basic questions to ask your doctor include:
- What's likely causing my child's symptoms?
- What other conditions could cause these symptoms?
- What tests will my child need?
- What is the best course of action?
- Will rheumatic fever or its treatment affect my child's other health conditions?
- How much do I need to restrict my child's activities?
- Is my child still contagious? For how long?
- What type of follow-up is needed?
- Are there brochures or other printed material that I can have? What websites do you recommend?
In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask questions during your appointment.
What to expect from your doctor
Your doctor is likely to ask you questions, such as:
- When did your child's symptoms begin?
- How have they changed over time?
- Has your child had a cold or flu recently? What were the symptoms?
- as your child been exposed to strep throat?
- Was your child recently diagnosed with strep throat or scarlet fever?
- If so, did your child take all of the antibiotics as prescribed?