Impact of human immunodeficiency virus on survival after liver transplantation: analysis of United Network for Organ Sharing database

BACKGROUND: The outcome of liver transplantation (LT) in patients infected with human immunodeficiency virus (HIV) has been a matter of controversy. METHODS: A retrospective cohort study was performed to assess the impact of HIV on LT survival by using United Network for Organ Sharing registry Standard Transplant Analysis and Research files. RESULTS: A total of 138 HIV(+) and 30,520 HIV(-) patients who were > or =18 years old and underwent LT during the highly active antiretroviral therapy era (starting January 1, 1997) in the United States were included. Among all HIV(+) patients, the estimated 2-year survival probability was lower (70%) than among non-HIV patients (81%). This excess risk appeared entirely among those with coinfections, that is, HIV with hepatitis B virus or hepatitis C virus (HCV), as none of the 24 HIV-infected patients who did not have hepatitis B virus or HCV died during an average of 1.2 years of follow-up per person. Among HCV(+) patients, those with HIV coinfection had significantly lower survival rates than patients without HIV (P=0.006). Controlling for age, coinfection, Model for End-Stage Liver Disease scores, and other potential confounders in a proportional hazards regression analysis, HIV(+) patients had a hazard ratio of 1.41 (P=0.14, 95% confidence interval: 0.90-2.22) for mortality after LT. CONCLUSION: HIV(+) patients without HCV coinfection seemed to have good prognosis, whereas patients who had HIV/HCV coinfection had poor outcomes, which were significantly worse than that seen in those with HCV alone.     

Blocking indoleamine dioxygenase activity early after rat liver transplantation prevents long-term survival but does not cause acute rejection

In a well-characterized rat model of liver transplantation, Piebald Virol Glaxo strain livers are accepted long term in fully mismatched Dark Agouti recipients (tolerance; TOL), but rejected in Lewis recipients (rejection; REJ). Spontaneous tolerance induction is associated with increased interferon-gamma expression, and we examined the role of the interferon-gamma-inducible immunomodulatory enzyme indoleamine dioxygenase (IDO) in this model. On day 3 after transplantation, IDO expression in the spleen of TOL recipients was significantly greater than in REJ. The B-cell population accounted for this early IDO increase. Intragraft expression of IDO increased to the same extent in both TOL and REJ. IDO inhibition for 7 days after transplantation reduced survival, but did not cause acute rejection of the liver in the TOL model. In conclusion, the differential IDO expression by B lymphocytes in the spleen of TOL recipients is not critical for preventing acute rejection.