Immune Thrombocytopenia in an Adult With X-linked Agammaglobulinemia: A Case Report.

In patients with X-linked agammaglobulinemia (XLA), serum immunoglobulins are almost completely lacking. The prevalence of autoimmune diseases is low in XLA compared with other primary immunodeficiency diseases because antibodies are absent in XLA. Immune thrombocytopenia (ITP) is considered an antibody-mediated disease characterized by increased platelet destruction, and adult-onset ITP in XLA has not been reported in detail. The case of a 29-year-old Japanese man with XLA and ITP is described. The patient was treated with prednisolone and intravenous immunoglobulins, resulting in rapid improvement of thrombocytopenia. Clinicians should consider co-existing ITP when progressive thrombocytopenia is observed in a patient with XLA.