The role of circulating immune complexes and biocompatibility of staphylococcal protein A immunoadsorption in mitomycin C-induced hemolytic uremic syndrome

Mitomycin-induced hemolytic uremic syndrome (HUS) Is a life-threatening complication of this therapy, and Increased levels of circulating Immune complexes and hypocomplementemia have been found In some patients. We further characterize the role of Immune complexes In mitomycin-HUS by showing that removal of these complexes by Immunoadsorption with staphylococcal protein A columns correlates with temporal Improvement In the microangiopathic hemolytic anemia In this disorder. Two Immune complexes bound to the protein A column were Identified: an 11S platelet-aggregating protein and a 15S non-platelet-aggragating protein. In addition, the patient had anaphylactoid reactions at the onset of Immunoadsorption similar to first-use dialysis reactions that correlated with Increases In complement 3a and 5a, Interleukin-1 (IL-1), IL-6, and tumor necrosis factor levels. This case suggests that platelet-aggregating and complement-fixing circulating Immune complexes are, In part, a proximate cause for mitomycin C-induced HUS. Therapy for mitomycin (HUS) with protein A columns should continue until circulating Immune complexes reach undetectable levels and serum complement levels return to the normal range.