Neonatal Th activation.

A case is reported of a 1-month-old infant with bowel obstruction and suspected sepsis whose red cells were found to be Th activated during the course of evaluating weakened A antigen activity. Neither Th activation nor weakened A antigen activity was present on the red cells of either parent. The Th activation and the weak reactivity obtained with commercial anti-A reagents were unrelated.

Fulminant Plasmodium falciparum infection treated with exchange blood transfusion.

A 48-year-old physician, who was not undergoing malaria chemoprophylaxis, contracted Plasmodium falciparum while working in eastern Thailand. In the hospital, he had a peak parasitemia of 72% RBCs infected, associated with CNS dysfunction. As an adjunct to chemotherapy, a double-volume whole-blood exchange transfusion was performed on the first hospital day, dropping the parasitemia to less than 1% within 32 hours. The patient's clinical condition improved, with a prompt reversal of CNS, hepatic, and renal complications. These results, combined with those in previously reported cases, suggest that exchange transfusion should be considered more generally as a life-saving procedure in P falciparum infections.

Delayed hemolytic transfusion reaction with four antibodies undetected by pretransfusion tests.

A case of delayed hemolytic transfusion reaction in a 43-year-old patient is presented. Pretransfusion tests revealed no antibody, but tests performed when the reaction occurred demonstrated four. Ten months and 15 months later, when the patient's serum was again tested, the antibodies were undetectable. The significance of such antibodies is discussed.