Neutrophil (PMN) bactericidal activity, phagocytosis, and nitroblue tetrazolium (NBT) reduction were evaluated in 18 children with untreated or relapsing acute leukemia and 20 children in hematologic remission. Half of the patients in relapse demonstrated abnormal PMN bactericidal activity, while remission patients had essentially normal P M N bactericidal activity. Phagocytosis of Staphylococcus aureus was normal in relapse a n d remission subjects. N B T reduction by PMN's of leukemic patients was significantly lower than that of c o n trols, but there was no correlation between decreased NBT-reductase activity a n d decrcased bactericidal power. Six patients i n remission had received intensive chemotherapy for more than 4 years, and all demonstrated normal PYN functions. Among relapse patients with abnormal P M N bactericidal activity 63% eventually developed severe bacterial infections. By comparison, 20% of the relapse patients with normal P M N bactericidal activity subsequently developed severe infections. T h e P M N dysfunction observed in relapse patients suggests that abnormal P M N bactericidal activity may contribute the increased susce~,tibility to bacterial infections during leukemic relapse.
Cancer 972194-2200, 1976.
ORBIDITY DUE T O INFECTION BOTH DURING
M relapse and during remission remains alarmingly high in children with acute leukemia.' While neutropenia probably accounts for most of the bacterial infections i n these patients, dysfunction of the remaining neutroplds (PXIN's) might be an additional infection promoting factor.4 Evidence for ineffective PAIN bactericidal activity has been presented