Impairment of opsonic function in children with hematologic malignancy during remission induction therapy.

The activity of complement-mediated opsonin was measured by the whole blood chemiluminescence method in 17 children with hematologic malignancy (including 6 with ALL, 7 with ANLL and 4 with non-Hodgkin's lymphoma) during remission induction therapy. The activity of opsonin, which was at the normal level before chemotherapy, decreased in all of the children during the therapy. This phenomenon was especially marked in the children treated with L-asparaginase. Although no clear relationship was found between the decrease in opsonin activity and the susceptibility to infection, it was confirmed that in 4 children having an episode of sepsis or septic fever, the infection started when the granulocyte decreased to the nadir, and simultaneously the activity of opsonin decreased. Therefore, it may be reasonable to suspect the decrease in opsonin activity when treating children with such infections.