[Successful cord blood transplantation in a patient with adult-onset common variable immunodeficiency].

Common variable immunodeficiency (CVID) is the most frequently diagnosed congenital immunodeficiency and is characterized by dysfunctional antibody production. It often occurs at the age of ≥10 years. Here we reported a case of a 46-year-old man confirmed with adult-onset CVID. He was effectively treated with cord blood transplant (CBT). The patient was observed with repeated upper respiratory infection a few years back and was referred to our department owing to a marked decrease in neutrophil counts and progression of anemia. Laboratory tests confirmed hypogammaglobulinemia, but no autoantibodies were detected. Bone marrow aspiration showed a hypocellular marrow with predominantly mature lymphocytes. T-cell receptor excision circle assay revealed a reduction in T-cell neogenesis. Further, multicolor flow cytometry analysis revealed a low differentiation of B cells; subsequently, CVID was confirmed in the patient. The patient had a severe clinical course and therefore, received CBT for the treatment. After the transplantation, the hematopoiesis was restored and the serum immunoglobulin levels returned to normal. The patient exhibited a favorable clinical course. Nevertheless, there is no precise definition to establish the disease concept of CVID. Also, most of the potential cases are predominantly reported in adults. Therefore, further data on cases with CVID should be accumulated to establish the diagnostic criteria as well as treatment modalities.