Overt and subclinical reactions to streptokinase in acute myocardial infarction

The aims of this study were (1) to assess the possibility of predicting allergic reactions to streptokinase (SK) by measuring pretreatment antibody titers and by intradermal skin testing, and (2) to determine if SK is associated with subclinical changes in renal function. Specific anti-SK immunoglobulin G (IgG) and subclass IgG1 were assessed by enzyme-linked immunosorbent sorbent assays, and renal function was assessed by measurement of serum urea and creatinine in 204 patients with acute myocardial infarction. Twenty-six patients had 24-hour proteinuria loss and creatinine clearance assessed at presentation. Median IgG titer at presentation was 6 (range 0 to 10,000), and increased to 60 (range 0 to 18,000; p < 0.0001) on day 6. Fifteen of 180 patients (8.3%) had minor allergic reactions to SK; the median titer on admission for these patients was 5 (range 0 to 60), identical to those who tolerated SK uneventfully. No change was seen in serum urea or creatinine; for those treated with SK, the median value for proteinuria loss at day 0 was 0.45 g/liter (range 0.1 to 2), and decreased by day 5 to 0.1 g/liter (range 0.1 to 0.8; p = 0.0027). No significant proteinuria was seen in those who did not receive SK. The reactions to SK were minor, and could not be predicted on the basis of IgG titers at presentation. Significant proteinuria was found in the first 24 hours in SK-treated patients, but not in those who did not receive SK, and it resolved by day 5.