The impact of chemotherapy and hematopoietic stem cell transplantation on humoral immunity to vaccine-preventable diseases

BACKGROUND, OBJECTIVES The antibody titer of vaccine-preventable disease in 70 patients who underwent chemotherapy or haemopoietic stem cell transplantation (HSCT) was assessed in order to evaluate the seroprotection after treatment and the feasibility and the efficacy of a policy of revaccination. METHODS Serum antibody titers of 70 patients for hepatitis B (HBV), Rubella, Varicella-zoster (VZV), Measles, Mumps, Polio viruses, Clostridium tetani (C. tetani) and Streptococcus pneumoniae (S. Pneumoniae) were analysed. RESULTS After chemotherapy, a lack of protective antibody titers against HBV, Rubella, VZV, Measles, Mumps, Polio viruses, C. tetani and S. Pneumoniae were found in 53%, 45%, 46%, 46%, 43%, 21-26%, 88% and 55% of patients, respectively. In patients who were tested both before and after chemotherapy, the loss of immunity was respectively 39%, 43%, 38%, 42%, 32%, 33%, and 80%. A low number of B-lymphocytes was associated with the loss of immunity against Measles (p=0.04) whereas a high number of CD8+ T-lymphocytes was associated with the loss of immunity against VZV (p=0.03). A single booster of vaccine dose resulted in a seroprotection for HBV, Rubella, VZV, Measles, Mumps, Polio viruses, C. tetani and S. Pneumoniae in 67%, 83%, 80%, 67%, 33%, 100%, 88% and 67% of patients, respectively. After HSCT, the rates of lack and loss of vaccine immunity differ by the infectious disease considered. CONCLUSIONS We confirm that seroprotection for vaccine-preventable disease is affected by treatment for pediatric malignancy. A single booster dose of vaccine might be a practical way to restore vaccine immunity in patients after chemotherapy.