Peppers BP, et al. - Researchers herein compared the levels of α₁-antitrypsin in subjects with immunodeficiency with and without bronchiectasis, presuming that patients with humoral immunodeficiencies on gammaglobulin infusions and bronchiectasis have lower median levels, but not necessary “classically” deficient levels, of α₁-antitrypsin compared with those without bronchiectasis. They found that median α₁-antitrypsin levels and phenotype in subjects were related to humoral immunodeficiency and their bronchiectasis status. The findings lend support to the idea that what is considered a “normal or protective” α₁-antitrypsin range might need to be refined for patients with humoral immunodeficiency on gammaglobulin therapy.