| Abstract: | Fifteen recently diagnosed patients with acute leukemias admitted for induction chemotherapy were selected for study. When thrombocytopenic (venous platelet count <20 × 109/1) these patients received prophylactic platelet transfusions. A total of 67 platelet transfusion therapies were administered and evaluated. Using the Raji cell radioimmunoassay, the serum concentrations of circulating immune complexes (CIC) were measured immediately before and 10–12 hr after each platelet transfusion. In 36 instances, elevated values of CIC were present in the recipient's pretransfusion samples, the corresponding posttrans-fusion values being significantly lower (P < 0.05). Furthermore, in those 36 instances the mean percentage for the posttransfusion platelet increment was significantly lower (P < 0.001) than in the remaining 31 instances in which normal pretransfusion values of CIC were measured. We conclude that CIC were an important factor in rapidly removing transfused platelets from the circulation, thereby, adversely affecting the benefit of platelet transfusions. |
