Ethnic disparities in outcome from posttransplant infections

Black transplant recipients have decreased graft survival and increased rejection rates compared with whites. Because increased rejection rates may lead to more immunosuppression in black recipients, ethnic differences may exist for outcomes of posttransplant infectious complications. All episodes of infection between December 1996 and October 1998 on the transplant services at the University of Virginia Health Sciences Center were prospectively evaluated. Parameters recorded included self-designated ethnicity, demographics, APACHE II scores, laboratory and microbiologic data, immunosuppression, episodes of rejection, and outcome measures. Evaluation of 303 episodes of infection demonstrated an increased mortality rate for white compared with black recipients (19% vs. 3%, P = 0.0006) despite having a similar severity of illness (APACHE II score). Among renal transplant recipients, episodes of infection occurring in black recipients (n = 46) were also associated with a decreased mortality rate versus whites (n = 89) (0% vs. 15%, P = 0.006) and shorter mean length of stay (12 +/- 2 vs. 25 +/- 4 days, P = 0.002) despite similar severity of illness and rejection rates. For posttransplant infections in liver transplant recipients, blacks (n = 23) demonstrated a trend toward decreased mortality (9% vs. 26%, P = 0.07) but equal lengths of stay despite similar APACHE II scores, rejection rates, and age. White liver transplant recipients had an increased incidence of viral infections (15% vs. 0%, P = 0.03). All other infecting organisms were similar. The unexpected finding of a significantly decreased rate of mortality associated with posttransplant infections in black recipients remains largely unexplained but may be related to subtle differences in immune response between racial or ethnic groups.