Bronchiolitis obliterans syndrome, hypogammaglobulinemia, and infectious complications of lung transplantation

Background: Because infection has been associated with the development of bronchiolitis obliterans syndrome (BOS), we hypothesized that post-transplant hypogammaglobulinemia would be associated with infection and BOS. Methods: Cross-sectional levels of serum immunoglobulins were measured on 2 occasions in our transplant cohort and models developed to explain serum immunoglobulin levels and BOS-free survival. Results: A total of 139 patients (median age, 46.6 years) were evaluated at 47 months (range, 15-74 months) after transplant, and 87 were re-evaluated at 72 months (40-107 months). Of this cohort, 44% were immunoglobulin (Ig) G deficient and levels remained stable across the study period, and 27% were IgA deficient and levels fell slightly over time (p = 0.003). Both immunoglobulin classes were lower in patients with a history of invasive fungal infection, whereas IgA levels were lower in patients with a history of community-acquired respiratory viral infection. Low IgG was independently associated with shorter BOS-free survival (hazard ratio, 0.79; 95% confidence interval, 0.71-0.88;