Detrimental Association of Hypogammaglobulinemia With Chronic Lung Allograft Dysfunction and Death Is Not Mitigated by On-Demand Immunoglobulin G Replacement After Lung Transplantation.

Background: Hypogammaglobulinemia (HGG), immunoglobulin G (IgG) <700 mg/dL, is associated with infections, chronic lung allograft dysfunction, and death following lung transplantation. This study evaluates the use of on-demand intravenous IgG in lung transplant recipients with HGG. Materials and Methods: This single-center retrospective cohort study of adult lung recipients evaluated 3 groups, no, untreated (u), or treated (t) HGG at first IgG administration or a matched time posttransplant. Primary outcome was freedom from allograft dysfunction. Secondary outcomes included development of advanced dysfunction, rejection, infection burden, and mortality. Results: Recipients included 484 (no HGG: 76, uHGG: 192, tHGG: 216). Freedom from chronic allograph dysfunction was highest in the non-HGG group 2 years post-enrollment (no HGG 77.9% vs uHGG 56.4% vs tHGG 52.5%; P = .002). Freedom from advanced dysfunction was significantly different 2 years post-enrollment (no HGG 90.5% vs uHGG 84.7% vs tHGG 75.4%; P = .017). Patients without HGG and those with uHGG had less mortality at 2 years post-enrollment (no HGG 84.2% vs uHGG 81.3% vs tHGG 64.8%; P < .001). Gram-negative pneumonias occurred more often in the tHGG group (P = .02). Conclusions: Development of chronic lung allograft dysfunction, patient survival, rejection burden, and key infectious outcomes in lung transplant recipients were still problematic in the context of on-demand IgG therapy. Prospective studies are warranted. [ABSTRACT FROM AUTHOR]