Diabetes Resistant to Subcutaneous Insulin: Effect of Aprotinin

To the Editor: We have reported on a group of exceptionally“brittle”diabetics whose clinical features resemble those of the patients described by Dr. Freidenberg and his colleagues in the August 13 issue.¹ All the patients are female; in many the disease is not controlled by doses of more than 100 units of insulin a day, injected or infused subcutaneously. Near normoglycemia is restored by continuous intramuscular infusion of insulin,² which presumably bypasses a barrier to subcutaneous absorption. Recently, we measured the breakdown of Radio-labeled and native insulin by subcutaneous-tissue biopsy specimens. The rate of insulin degradation in vitro by. . .