CD40LG and Respiratory tract infection: We present a 49-year-old female (case 16) diagnosed with common variable immune deficiency, recurrent respiratory tract infections, cough attacks, periodic hematuria, dysuria, and hypogammaglobulinemia (IgG < 34 mg/dl; IgA < 27 mg/dl; IgM < 17 mg/dl, IgE < 17.9 IU/ml).