How is rheumatic fever diagnosed?
Diagnosis of rheumatic fever is done by taking a sample of the patient’s blood to test it for antibodies to the streptococcus germs. A record of the patient’s heart's activity, called an electrocardiogram, may show changes from the normal pattern. In
addition, an ultrasound test called an echocardiogram may help diagnose valve problems.
If rheumatic fever is suspected, a swab is taken from the throat to try and culture the infective bacteria. A blood test may be done to look for streptococcal infection by demonstrating the presence of Streptococcal Antibodies (ASO or Anti-Streptolysin-O). A chest x-ray may also be taken to see the size of the heart and analyse if it is inflamed or not. An Electrocardiogram (ECG) may be done to monitor the electrical activity of the heart and echocardiography to image the interior of the heart and the valves.
Given the different manifestations of this disease, there is no specific test which can definitively establish a diagnosis. In addition to a careful physical examination of heart sounds, skin, and joints, blood samples may be taken as part of the evaluation. These include tests for recurrent strep infection, complete blood counts, and sedimentation rate. As part of the cardiac evaluation, an electrocardiogram may also be done. In order to standardize the diagnosis of rheumatic fever, several minor and major criteria have been developed. These criteria, in conjunction with evidence of recent streptococcal infection, establish a diagnosis of rheumatic fever. |
