A case of common variable immunodeficiency associated with cyclic thrombocytopenia.

A 12 year old boy was found to be deficient in immunoglobulins (Ig) A, G2 and G4, and common variable immunodeficiency was diagnosed. He also had cyclic thrombocytopenia at intervals of approximately 28-30 days. His bone marrow revealed normocellular with slightly decreased megakaryocytes. In vitro colony assays showed markedly imparied megakaryocytopoiesis, erythropoiesis and granulopoiesis. Platelet-associated IgG was elevated at his thrombocytopenic phase. Direct Coombs' test was repeatedly positive. Although not defined at present, we suggest the autoimmune nature of the disease.