CD40LG and common variable immunodeficiency: CVID patients with PCP IgA and IgM concentrations above 150 U/mL and 20 U/mL, respectively have been shown to have a lower risk of developing pneumonia and bronchiectasis than those with either a PCP Ig Mconcentration<20 U/mL only or those with both concentrations below both the above cut-offs [3].