Low %CD19 (6%; RV: 8-45*).Absent IgA with low IgG (36 mg/dL; RV: 345-1213**) and normal IgM.Moderately reduced proliferation assays.Poor growth and weight gain, facial dysmorphism, dysplastic mitral valve and aortic valve insufficiency, delayed teeth eruption, autoimmune hypothyroidism, atrophic gastritis, recurrent infections, hearing loss. Here, CD19 is linked to aortic valve insufficiency.