The likely diagnosis of CVID was based on the following criteria: frequent bacterial infections (consequently leading to advanced chronic pulmonary disease and bronchiectasis), growth retardation and failure to thrive, myocardiopathy, hepatomegaly, autoimmune phenomena (similar to scleroderma), decreased levels of IgG, IgA, and IgM, absence of isohemagglutinin synthesis, and poor response to active immunization (tetanus toxoid). The gene discussed is CD40LG; the disease is bronchiectasis.