Pathogenic TNFRSF13B Variant in an Adult Japanese Patient with Common Variable Immunodeficiency.

Common variable immunodeficiency (CVID) is a primary B cell immunodeficiency disorder. Symptoms do not develop immediately after birth, and patients are often diagnosed in childhood and adulthood. These patients often develop autoimmune diseases and malignant tumors. We herein report a 50-year-old woman with severe hypogammaglobulinemia and recurrent respiratory tract infections who was diagnosed with CVID. Target sequencing showed a TNFRSF13B heterozygous frameshift variant. The patient had many comorbidities, probably caused by a CVID-induced immune imbalance. Physicians who treat adult patients are often unaware of CVID. CVID should be recognized as a differential diagnosis in hypogammaglobulinemia and recurrent infections.