Hematologic complications of primary immune deficiencies.

Primary immune deficiencies have an estimated overall incidence of 1 in 10,000 individuals. These disorders are diverse, depending on the specific immune functions involved, and lead to chronic or recurrent infections, inflammatory conditions, and a variety of autoimmune diseases. The most common autoimmune disorder is immune thrombocytopenic purpura (ITP), followed by autoimmune hemolytic anemia (AHA). While cytopenias are common in all the congenital immune diseases, they are particularly common in the antibody defects, common variable immunodeficiency and selective immunoglobulin A deficiency. In common variable immunodeficiency, ITP occurred in 7.6% of the patients and AHA in 4.8%. Treatment options include corticosteroids, intravenous immunoglobulin (i.v.Ig), anti-D, and splenectomy. Although the association between cytopenias and congenital immune deficiency is unclear, defects in T-cell regulation, cytokine defects, abnormal apoptosis, and abnormal production of immunoglobulins with autoimmune features are potential mechanisms.