Tetanus immunity in patients with hematological malignancies

The aim of this study was to investigate long-term immunity to tetanus toxoid among patients with hematological disease who had been treated with conventional doses of chemotherapy. Altogether 206 patients with different hematological malignancies were included in the study. There were marked differences between the rates of seronegativity against tetanus, varying from 20% to 70% in different groups of study patients. We found that 21 of 80 (36%) patients with AML, 45 of 80 (56%) with ALL, 12 of 22 (54%) with lymphoma, 4 of 13 (31%) with myeloma and 2 of 11 (18%) with CML were not immune to tetanus. In a multivariate logistic regression model increasing age (P = 0.0001), lymphoid malignancy (P = 0.0005) and advanced disease stage (P = 0.0001) were independent risk factors for loss of tetanus immunity in patients with hematological malignancies.