Assessment of humoral immunity to poliomyelitis, tetanus, hepatitis B, measles, rubella, and mumps in children after chemotherapy

Patterns and correlates of preserved humoral immunity to vaccines in children following allogeneic hematopoietic stem cell transplantation

Data on preservation of vaccine immunity following allogeneic HSCT in children is limited. We investigated vaccine titers and sought correlations with patient characteristics in this study. Twenty-eight cases were retrospectively analyzed. Antibody concentrations against hepatitis A, hepatitis B, 3 poliovirus serotypes, tetanus, diphtheria, measles, mumps, rubella, varicella, and 13 pneumococcus serotypes were measured as part of planned monitoring following HSCT. Protective antibody levels were found for hepatitis A in 79% of the recipients, measles in 54%, all poliovirus serotypes in 50%, tetanus in 50%, rubella in 50%, varicella in 46%, hepatitis B in 46%, mumps in 43%, diphtheria in 29%, and ≥7/13 pneumococcus serotypes in 46%; lowest level observed for diphtheria and highest for hepatitis A prior to starting post-HSCT immunizations. In univariate analysis, patients with non-malignant diseases (P = .03) and without GvHD (P = .04) had more protective titers. A significant positive association was found among vaccine titers against the microorganisms or the serotypes of the same microorganism, which were administered together in the same product, including polio serotypes, diphtheria and tetanus, mumps, measles, and rubella. Higher degrees of sero-positivity are likely to be due to lack of prior chemotherapy in non-malignant disease cases and lesser immunosuppression in patients without GvHD. Monitoring long-term vaccine titers and administering vaccines accordingly could be evaluated for post-HSCT re-immunization practice.

Vaccine-Derived Immunity in Children With Cancer-Analysis of Anti-Tetanus and Anti-Diphtheria Antibodies Changes after Completion of Antineoplastic Therapy

BACKGROUND

Cancer survival rates and longevity of patients after therapy have significantly improved during the last decades. Thus durable protection against infections should be provided. The aim of the study was to compare the levels of vaccine-derived antibodies in children with cancer compared to those of healthy children and to investigate how therapy influences the levels of specific antibodies.

PROCEDURE

A group of 40 children, diagnosed with acute lymphoblastic leukemia (ALL) or solid tumor (ST), followed in Poznan University of Medical Sciences Department of Pediatric Hematology, Oncology and Bone Marrow Transplantation, were recruited for evaluation of humoral immunity. Antibody levels were checked before treatment and 3, 6, and 12 months after treatment.

RESULTS

In patients with ALL or ST, levels of IgG against tetanus and diphtheria were significantly lower than in the control group. Among ALL patients, 9% remained negative for tetanus and diphtheria antibodies 12 months after therapy. Among patients with ST 3 months after chemotherapy, there were no protective antibodies in 12% against tetanus, and in 18% against diphtheria. All patients reconstituted immunity 6 and 12 months after therapy.

CONCLUSIONS

Our data show that a considerable number of cancer patients lose immunity against diphtheria and tetanus after therapy. Compared to ST, patients with ALL lose protective antibody levels more often. Patients with ST reconstituted antibodies after the treatment cessation, while levels in ALL patients remained low.

Loss of antibodies and response to (re-)vaccination in children after treatment for acute lymphocytic leukemia: a systematic review

Intensified chemotherapy regimens resulting in improved survival of children with acute lymphocytic leukemia (ALL) lead to concerns about therapy-induced immune damage reflected by the loss of protection of previous immunizations and the efficacy of (re-)vaccination. The severity of secondary immunodeficiency, however, is not clear and knowledge is based on a limited number of studies. We performed a systematic review on literature concerning vaccination data of children with ALL published since 1980. Eight studies fulfilled the inclusion criteria. Regarding antibody titers after treatment, the number of children who had preserved the defined protection level for antibodies differed widely, ranging from 17 to 98% for diphtheria, 27 to 82% for Bordetella pertussis, 20 to 98% for tetanus, 62 to 100% for poliomyelitis, 35 to 100% for Haemophilus influenzae type B (HiB), 29 to 92% for mumps, 29 to 60% for measles and 72 to 92% for rubella. Most patients however responded to revaccination, demonstrating immunological recovery. Although the designs and results of the included studies varied widely, it can be concluded that cytostatic therapy for ALL in children results in a temporarily reduction of specific antibody levels. Memory is preserved but revaccination may be warranted. This is the first systematic review and the best possible current approximation of chemotherapy-induced immune damage in children after ALL treatment.