Streptokinase resistance in medical patients in Oslo

The streptokinase titrated initial dose (TID) was estimated in 31 2 patients consecutively admitted to a medical department in Oslo. 93% had a TID below 250,000 IU, 97% below 425,000 IU and 98.5% below 650,000 IU. No differences were found between the two sexes. The highest values were found in patients 50--60 years old. Otherwise, no differences were found between different age groups from 10 to 90 years of age. Two patients with extremely high TID values were both anamnestically prone to streptococcal infections. It is concluded that our standard initial dose of 250,000 IU of streptokinase is sufcient for the great majority of our patients. Pre-treatment test for TID is recommended only when recent streptococcal infections are suspected.