Quinine-induced immune thrombocytopenic purpura followed by hemolytic uremic syndrome

Immune thrombocytopenic purpura (ITP) mediated by quinine-dependent platele t reactive antibodies is well recognized. More recently there have been a n umber of reports of quinine-induced hemolytic-uremic syndrome (HUS). We des cribe a patient with quinine-induced immune thrombocytopenia who subsequent ly developed HUS after re-exposure to a single dose of this drug. To our kn owledge, this is the first such case reported. Multiple quinine-dependent a ntibodies have been characterized in the patient's serum. Initially, quinin e-dependent antibodies were directed solely against the platelet glycoprote in complex GPIb/IX. After rechallenge with quinine, there was broadening of quinine-dependent antibody specificities, which were now also directed aga inst the platelet glycoprotein complexes GPIb/IX and GPIIb/IIIa, endothelia l cells, and leukocytes, We have shown quinine dependent antibody-mediated endothelial cell activation, which supports an immunopathogenic role for qu inine-dependent antibodies in the causation of this disease. (C) 1999 by th e National Kidney Foundation, Inc.