Immunization of children receiving immunosuppressive therapy for cancer or hematopoietic stem cell transplantation.

In the past 3 decades, the number of immunocompromised children has increased steadily because of dramatic improvement in survival rates in certain malignancies as a result of intensive curative treatment regimens and an increase in the number of children undergoing life-saving hematopoietic stem cell transplantation (HSCT). Children receiving immunosuppressive therapy for cancer, as well as HSCT recipients, will benefit from vaccination but warrant close evaluation for a variety of reasons, such as the risk of developing severe infections, serious adverse events following certain vaccines, and decreased vaccine efficacy caused by poor immune response to vaccination. Various professional organizations have published vaccination guidelines for immunocompromised patients. Given their heterogeneity, recommendations for the immunization of immunocompromised patients may not be universally applicable. The safety of many commonly used vaccines has not been established in immunocompromised children. In addition, no large-scale vaccine studies have evaluated the clinical outcome of disease prevention in this population. All killed vaccines are generally safe, while live vaccines may be administered to immunocompromised children in select circumstances, depending on the degree of altered immunocompetence and the underlying primary condition. Healthcare providers should be knowledgeable about the indications, contraindications, and precautions for vaccine administration in immunocompromised patients. To protect immunocompromised patients, all family, household contacts, and healthcare workers should also be immunized with all routinely recommended vaccines. Pediatricians play a crucial role in identifying and effectively communicating the risks and benefits of vaccines to immunocompromised patients and their parents.