A comparison between streptokinase/streptodornase and streptokinase on delayed hypersensitivity skin testing

The use of streptokinase (SK) to replace streptokinase/streptodornase (SK/SD) in delayed hypersensitivity skin testing was evaluated in 325 patients. Sixty patients responded to SK/SD (100 U of SK per 25 U of SD) and 36 to SK (375 U). Thirty-two responded to SK/SD but not to SK, and eight responded to SK but not to SK/SD. SK, at the dosage used, is not a suitable substitute for SK/SD in delayed hypersensitivity testing. SD may be the more potent recall antigen. Perhaps more importantly is that of 250 positive responders to a recall-antigen battery consisting of SK/SD, SK, Candida, Trichophyton, tetanus toxoid, purified protein derivative, and coccidioidin, 99.2% (248) would have been detected had the testing for SK and SK/SD not been done.