Rheumatic fever is a complication of having a strep throat. In some people, fighting off the strep infection causes other parts of the body to develop swelling or inflammation. This can happen even to those parts of the body that aren't directly infected by the virus.
One of the common and potentially dangerous effects of rheumatic fever is damage to the valves of the heart. This can lead to narrowed or leaky heart valves. The mitral (or bicuspid) valve, which permits blood to flow from the left atrium (upper chamber) to the left ventricle (lower chamber) of the heart, is affected most often. The aortic valve is frequently affected. The tricuspid and pulmonic valves are rarely affected.
Rheumatic fever only develops after a person has had a strep infection, which causes symptoms such as:
- Muscle aches
- Red and swollen tonsils
- Sore throat
Prompt treatment of a strep infection can prevent the development of rheumatic fever. In more than half of all cases, rheumatic fever may affect the heart valves (rheumatic carditis) and interfere with normal blood flow through the heart.
Even without treatment, though, only about three people out of every 10 who have a strep throat infection develop rheumatic fever. The signs of rheumatic fever usually appear about five weeks after the strep infection.
Symptoms of rheumatic fever are divided into major and minor ones. A doctor will make a diagnosis of rheumatic fever if:
- Two major signs are present, or
- One major and two minor signs are present in person who has had a strep infection.
- Inflammation (swelling) of your heart. About half the time people have a first attack of rheumatic fever, they develop this. If this happens, you may feel weak, short of breath or have chest pain. A physical examination or a test such as an electrocardiogram or chest X-ray may also indicate inflammation of the heart. The inflammation may not lead to permanent damage, but it can lead to scarring of the heart valves and damage severe enough to cause heart failure. Sometimes the damage isn't diagnosed until years after the rheumatic fever has gone away.
- Pain that moves from joint to joint. This usually affects your ankles, wrists, knees and elbows. This can cause painful swelling, redness and a feeling of heat
- A lack of coordination or uncontrollable jerky movements of your arms, legs and face. Your handwriting may become worse, for example. This symptom is known as chorea, Sydenham's chorea, rheumatic chorea or St. Vitus' dance. About one out of every 10 people who have rheumatic fever develops this. It usually disappears in a few weeks or months.
- Pink or faint red rashy patches that don't itch on your skin
- Lumps under the skin, even if the rash isn't there
- A blood test indicating inflammation
- Abnormal heartbeat on an electrocardiogram
- Heart murmurs that hadn't been present before
- Joint pain without inflammation
- Previous rheumatic fever or evidence of rheumatic heart disease
Causes and Risk Factors
It is not yet known what causes rheumatic fever. It appears that when some people's bodies fight off a strep throat infection, other parts of the body develop inflammation (swelling and tenderness). Research has focused on whether this is an abnormal response by the immune system to the antigens produced by some types of streptococcal bacteria. The possibility that some people have a genetic disposition to have this response is also being studied.
Your risk of developing rheumatic fever is greater if you are:
- Between the ages of 6 and 15 years
- A woman. The disease is twice as common in women as it is in men.
- In a situation where you have a greater chance of being exposed to streptococcus infections such as in a developing country where there is not enough food, overcrowding and poverty
- While it is relatively rare in the United States, there have been outbreaks over the last 20 years that tended to occur in white, middle class suburban neighborhoods or in rural areas. Additionally, more aggressive strains of streptococci appear to be returning to the United States.
No single test that can confirm a diagnosis of rheumatic fever.
It is important that your doctor make sure that your symptoms aren't caused by gout, sickle cell anemia, leukemia, embolic bacterial endocarditis, drug reactions or some forms of arthritis, all of which have symptoms similar to those of rheumatic fever.
Your doctor will usually do a physical examination and take your medical history. During the exam, he or she will look for achy, painful joints, swelling, rashes or lumps on your skin and shortness of breath and will check your heart for murmurs that weren¿t there before.
If the heart is involved, it is important that your doctor distinguish whether the symptoms you are experiencing are caused by Rheumatic carditis instead of birth defects of the heart that also cause heart murmurs. Additionally juvenile rheumatoid arthritis can sometimes begin suddenly and affect the heart in ways similar to that of rheumatic fever.
electrocardiogram (ECG) may show abnormal heart rhythms.
Because a diagnosis of rheumatic fever requires evidence that you have had a recent strep infection, your doctor may order a blood test to check for antibodies to streptococcal bacteria.
Treatment will vary depending on the symptoms, how severe they are and whether there is damage to the heart. Generally, treatment consists of getting rid of any remaining strep bacteria and treating the symptoms.
Treatment may include:
- Limiting your activity to manage joint pain, chorea or symptoms of heart failure.
- Pain relievers such as codeine or non-steroidal anti-inflammatory drugs (NSAIDS) such as aspirin to relieve mild joint pain. More aggressive pain relievers may be needed if the pain is severe.
- NSAIDS such as aspirin to control inflammation if you have carditis.
- Corticosteroids such as prednisone for severe carditis, especially if it is associated with symptoms of heart failure.
- Antibiotics such as penicillin to assure that there are no more streptococcal bacteria left behind. It may be necessary to take antibiotics for years afterwards to prevent another attack of rheumatic fever. Without this precaution, additional attacks of rheumatic fever are common for three to five years after the first infection.