Antibody deficit can develop as a primary immune deficiency caused by inherited genetic abnormalities or as a secondary result of a variety of reasons. This review seeks to synthesize current data on the causes of secondary antibody shortage, as well as evidence for the use of preventive replacement immunoglobulin where possible. Immune-mediated treatments, ranging from monoclonal antibodies to new B-cell-targeted medicines, have expanded the list of probable iatrogenic causes of antibody shortage.

Secondary antibody deficit is caused by B-cell lymphoproliferative illness, most notably chronic lymphocytic leukemia and multiple myeloma, protein-losing syndromes, lymphatic circulation abnormalities, increased immunoglobulin catabolism, and an increasing number of therapeutic drugs. At-risk patients should be closely monitored for hypogammaglobulinemia, B-cell function should be defined where appropriate with specific antibody responses to immunization antigens, and patients should be treated with prophylactic antibiotics and/or replacement immunoglobulin where there is a significant burden of infections.