Meta-analysis finds 4% HBV transmission risk in kidney transplants from active HBV donors

BACKGROUND: Potential kidney donors with active hepatitis B virus (HBV: positive hepatitis B surface antigen [HBsAg] and/or nucleic acid test [NAT]) are usually declined for HBsAg-negative recipients. Safety may be improved by recipient vaccination and/or antivirals, thereby increasing transplantation opportunities. We quantified HBV transmission risk in this setting to inform donation decisions. METHODS: Systematic review and meta-analysis (MEDLINE, to November 2024) of cohorts comprised of kidney donors with active HBV intentionally used for HBsAg-negative recipients. Transmission was defined as new HBsAg or NAT positivity posttransplant. Transmission proportions and exact 95% confidence intervals (CIs) were pooled using generalized linear mixed models with logistic transformation and random effects. RESULTS: We included 20 cohorts involving 600 HBsAg-negative recipients from donors with active HBV. Most donors were living (52%), with negative NAT (60%). Most recipients had positive surface antibody (>10 IU/L, 86%); many were core antibody positive (47%). Antiviral prophylaxis was given to 49% recipients, varying in type, duration, and strategy. There were 29 of 600 HBV transmissions, mostly transient low-level viremia only (62%). The pooled transmission rate was 4.0% (95% CI, 1.8%-8.3%) with low heterogeneity ( I2  = 0%) but some between-study variance (Tau 2  = 1.21). Transmission rates were higher where all donors had positive NAT (16.0%; 95% CI, 10.2%-24.3%), and lower where all recipients were living (0.8%; 95% CI, 0.1%-6.4%) or had positive surface antibody (1.4%; 95% CI, 0.2%-8.8%). Three deaths because of HBV transmissions occurred, all among recipients not taking posttransplant antiviral prophylaxis. CONCLUSIONS: Given low transmission rates and mitigating strategies, kidney transplantation may be considered from donors with active HBV, with donor/recipient risk stratification, consent, and monitoring/prophylaxis.