Rheumatic fever - Diagnosing rheumatic fever
NHS Choices Medical Reference
As rheumatic fever can cause so many different symptoms, a type of checklist known as the 'Jones Criteria' is used to help diagnose it.
Your GP will use the Jones Criteria to check whether you have signs and symptoms strongly associated with rheumatic fever.
These are divided into:
- major signs and symptoms - which you would normally expect to see in a case of rheumatic fever
- minor signs and symptoms - which can sometimes occur in a case of rheumatic fever
The major signs and symptoms are:
- inflammation of the heart (carditis), which can cause symptoms such as shortness of breath and chest pain
- pain and swelling (arthritis) affecting multiple joints
- jerky involuntary body movements and emotional outbursts (Sydenham chorea)
- a painless, non-itchy skin rash
- bumps or lumps developing underneath the skin
The minor signs and symptoms are:
- joint pain, but less severe than arthritis joint pain
- a high temperature (fever), usually over 39ºC (102ºF)
- blood tests show you have high levels of inflammation in your body
- an irregular heart rhythm
A confident diagnosis of rheumatic fever can usually be made if:
- at least two major signs and symptoms are present, or
- there are two minor signs and symptoms and at least one major sign or symptom
While some of the signs and symptoms listed above can be assessed by a physical examination, others, such as inflammation of the heart, need to be tested. Tests used to diagnose rheumatic fever are outlined below.
You will usually need to have an electrocardiogram (ECG). During an ECG up to 12 adhesive electrodes are attached to certain areas of the body, such as the arms, legs and chest.
A machine then measures the electrical activity of your heart, so that your doctor can check for any abnormal heart rhythms. Inflammation of the heart is a common complication of rheumatic fever, so it is important that any abnormal heart rhythms are detected early on so that prompt treatment can be given.
A number of different blood tests may also be used to look for indications of rheumatic fever. The first tests the level of C reactive protein (CRP) in your blood. CRP is produced by the liver. If there is more CRP in the blood than usual this means there is inflammation in the body.
Another blood test is known as erythrocyte sedimentation rate (ESR). In an ESR test a sample of your red blood cells is placed into a test tube of liquid. They are then timed to see how fast they fall to the bottom of the tube. If they are sinking faster than usual, this could mean that you have an inflammatory condition such as rheumatic fever.