We have investigated the relationship between oxygen free radicals and acute rheumatic fever with regard to diagnosis of the disease process. At the time of diagnosis, we measured the levels of reactive oxygen molecules in the plasma, this being a parameter for oxygen free radicals, and discovered the levels to be significantly higher when compared with those measured in a control group (P< 0.05). The levels measured in the plasma, however, were not statistically different among patients with and without carditis.

We found a progressive decrease in the levels measured in the plasma when patients with acute rheumatic fever were tested on the 15th, 30th and 90th days subsequent to diagnosis. By the 90th day, levels measured in the plasma were still higher, but no longer significantly elevated, when compared with the control group. The present study is preliminary, but raises the possibility that measurement of oxygen free radicals in the plasma could be used as a laboratory test for active state of acute rheumatic fever. Further investigations will be needed, nonetheless, to determine the clinical application of this technique.