LAUSR

INTRODUCTION After chemotherapy, children with acute lymphocytic leukemia lose immunity and need revaccination against tetanus and diphtheria. However, little is known about immunity in adult patients after treatment for hematological malignancies. In this study, we assessed serology levels against polio, diphtheria and tetanus in adult patients after conventional treatment for leukemia and lymphoma. PATIENTS One hundred and four patients, age 61 (19-86) years, were included at a median of 18 (4-77) months after chemotherapy for acute leukemia (n = 24) or lymphoma (n = 80). Pre-treatment sera were available in 73 cases for a pre-versus post treatment comparison. Healthy, age- and sex matched controls were available for 47 pts. METHODS Tetanus antibodies were quantified using ELISA, and antibody levels ≥0.01 IU/mL were considered protective. Diphtheria antibodies were analyzed using neutralization test (n = 60) or by ELISA (n = 44). In both tests values ≥0.01 IU/mL were considered protective. Antibodies against poliovirus serotype 1 and 3 were assessed by a neutralizing test. A microneutralization titer of ≥2 was considered protective. RESULTS Tetanus: There were significantly more non-immune patients after treatment (24%), compared to before (12%), p = 0.02. Post-treatment antibody levels were significantly lower than pre-treatment levels (p = 0.02). Diphtheria: There was a trend, p = 0.06, towards more non-immune patients after treatment (21%) compared to before (27%). Antibody levels post treatment were lower than pre treatment levels (p = 0.03) and lower than controls (p = 0.01). Polio: There was no significant difference in the number of non-immune patients before vs after chemotherapy for either PV1 or PV3. Protective immunity against serotype 1 and 3 was preserved in 90 and 97%, respectively. CONCLUSIONS After standard chemotherapy for leukemia and lymphoma a significant proportion of patients had impaired humoral immunity to diphtheria and tetanus. However, polio immunity was well preserved.