Acquired hypogammaglobulinemia in HIV‐positive subjects after liver transplantation

Abstract

As more solid organ transplantations are performed in patients infected with human immunodeficiency virus (HIV), post-transplant complications in this population are becoming better defined. Using serum samples from the Solid Organ Transplantation in HIV: Multi-Site Study, we studied the epidemiology of acquired hypogammaglobulinemia (HGG) after liver transplantation (LT) in 79 HIV-infected individuals with a median CD4 count at enrollment of 288 (interquartile range 200-423) cells/μL. Quantitative immunoglobulin G (IgG) levels before and after LT were measured, with moderate and severe HGG defined as IgG 350-500 mg/dL and <350 mg/dL, respectively. Incidence, risk factors, and associated outcomes of moderate or worse HGG were evaluated using Kaplan-Meier estimator and proportional hazards (PH) models. The 1-year cumulative incidence of moderate or worse HGG was 12% (95% confidence interval [CI]: 6-22%); no new cases were observed between years 1 and 2. In a multivariate PH model, higher pre-transplant model for end-stage liver disease score (P = 0.04) and treated acute rejection (P = 0.04) were both identified as significant predictors of moderate or worse HGG. There was a strong association of IgG levels <500 mg/dL with non-opportunistic serious infection (hazard ratio [95% CI]: 3.5 [1.1-10.6]; P = 0.03) and mortality (3.2 [1.1-9.4]; P = 0.04). These associations held after adjustment for important determinants of infection and survival among the entire cohort. These results suggest that a proportion of HIV-positive LT recipients will develop clinically significant HGG after transplantation.