Vaccination in Immunocompromised Patient Populations

Abstract

In industrialized as well as in developing countries, the population of children and adults who are immunocompromised and suffer from increased susceptiblity to infections is steadily increasing. In contrast to the primary immunodeficiency disorders, which are rare diseases predisposing to infections because of relatively well defined abnormalities of the immune system [1], secondary immunodeficiency disorders are not due to inherited single gene defects leading to impaired lymphocyte function, but include a wide range of abnormalities of the immune system associated with a large variety of underlying conditions. In general, altered immunocompetence can be the result of bacterial, parasitic, or viral infections such as human immunodeficiency virus (HIV) infection, hematologic malignancies such as leukemia and lymphoma, nonhematologic localized or generalized malignancies such as breast cancer, or immunosuppressive therapy, e.g., with alkylating agents or antimetabolites, radiation therapy, high doses of corticosteroids, and other drugs used in the course of organ and bone marrow transplantation and in the treatment of autoimmune diseases and malignant tumors [2]. Alterations of the immune system can also be due to medical conditions other than immunosuppressive therapy, such as end-stage renal failure requiring hemodialysis [3,4], and is also observed in low birth weight infants or in old age.