Depression of immunologic reactivity of patients with acute leukemia

The immunologic status of 146 patients with acute leukemia has been explored at different stages of the disease, before and during various treatments, and compared with clinical and hematologic status. Preestablished delayed hypersensitivity (D.H.) was studied by intradermal injection of 4 antigens; antibody response by injection of polio vaccine. D.H. reactions were found to be slightly impaired before treatment. During induction therapy, the immunodepression involves mainly antibody production, while D.H. is preserved in most cases. Abolition of D.H. reactions occur during drug-induced aplasias, and strongly correlates the severity of the aplasia. Maintenance treatments tested did not significantly affect immunologic reactivity of patients in remission.