Comparison of the erythrocyte sedimentation rate, C-reactive protein, serum diphenylamine, and tetrammonium tests in rheumatic fever and rheumatic heart disease.

The difficulty in assessing the activity of the disease process in rheumatic fever and rheumatic heart disease is apparent from the large number of laboratory tests which have been used from time to time. In a previous study (Eastham, Szekely, and Davison, 1958) we have attempted to assess the value and limitations of the C-reactive protein test as a measure of rheumatic activity in a group of unselected cases of rheumatic fever and rheumatic heart disease. In the present study, using the same clinical material, we have correlated four laboratory tests in the hope that it might be possible to demonstrate a distinct advantage of one test over the others. In acute rheumatic fever, serum electrophoresis shows that the albumin content falls, while alpha-1, alpha-2 and gamma globulin concentrations rise (Dole, Watson, and Rothbard, 1945). Ernstene (1930) showed that plasma fibrinogen concentration rose and the haematocrit level fell. According to Jackson, Kelly, Smith, Wang, and Routh (1953), these changes are reflected in the rise in the erythrocyte sedimentation rate. Roantree and Rantz (1955) showed that C-reactive protein occurred in the serum early in the course of acute inflammation. Coburn, Moore, and Haninger (1953) demonstrated that the serum diphenylamine reaction paralleled the erythrocyte sedimentation rate, and Jacox (1951) showed a similar correlation between the serum tetrammonium turbidity and the erythrocyte sedimentation rate in cases of rheumatic fever. The last two tests were, therefore, selected for comparison with the erythrocyte sedimentation rate and the serum C-reactive protein in our series. Methods and Material