A new application of plasma exchange in insulin dependent diabetes mellitus.

An insulin dependent diabetic patient was resistant to all but central venous insulin administration. For this reason plasma exchange was tried and it restored insulin responsiveness. An anti-insulin IgG antibody was identified in the patient's plasma. Plasma exchange reduced antibody levels and these correlated with daily insulin requirements. Kinetic analysis of anti-insulin antibodies, however caused us to doubt that they were the sole cause of the problem. Although the mechanism remains unclear, plasmapheresis proved to be an effective method of treating this patient's insulin resistance.