An Acquired Heparin-Like Anticoagulant In An 8 Month Old With Monoblastic Leukemia

Abstract

Well documented heparin-like anticoagulants have been reported in association with malignancy only in 3 adults with multiple myeloma. We report an 8 month old white male with acute monoblastic leukemia with an initial WBC of 358, 000/ul who was treated with adriamycin and ARA-C, developed a severe coagulopathy, and died 3 days later of presumed pulmonary and/or CNS hemorrhage. Liver and renal functions were normal and lysozyme was 112 mg/dl. The coagulation data were as follows:The factor V level was 11% and 2%, the factor VIII level was 69% and 85%, and the platelet count was approximately 50,000/μl both days. The thrombin time with mixing was 59 secs and after adsorption with “hepasorb” the thrombin time was 33 secs. Coagulation parameters did not change despite the infusion of fresh frozen plasma, proplex, hemofil, and platelets.Additional studies revealed: 1) Progressive shortening of the thrombin time when increasing amounts of protamine and PF4 were added to patient’s plasma. 2) Patient’s urine prolonged the thrombin time of normal plasma. This effect was neutralized by protamine and PF4. Urine from another patient with AMOL in relapse did not prolong the thrombin time of normal plasma. 3) Mucopolysaccharides were detected in the patient’s urine by the Berry spot test.The data suggest that the major coagulation abnormality in this patient was a circulating heparin-like anticoagulant. This is the first case report of an endogenous heparin-like anticoagulant in leukemia.