CD40LG and immune system disorder: His blood tests showed he had hypocalcemia with calcium 1.38 mmol/L and immunodeficiency with IgA 0.04 g/L (normal: 0.03–0.82 g/L), IgG 8.37 g/L (normal: 7.00–14.40 g/L), IgM 0.052 g/L (normal: 0.06–0.20 g/L).