Purpose: Risk factors, sites, and mortality of hospitalized cytomegalovirus (CMV) disease in renal transplant recipients have not been studied in a national population.
Methods: Therefore, 33,479 renal transplant recipients in the United States Renal Data System from 1 July 1, 1994 to June 30, 1997 were analyzed in an historical cohort study of patients with a primary discharge diagnosis of CMV disease (ICD9 Code 078.5x).
Results: Renal transplant recipients had an incidence density of hospitalized CMV disease of 1.26/100 person years, and 79% of hospitalizations for CMV disease occurred in the first six months post transplant. The leading manifestation of hospitalized infection was pneumonia (17%). In logistic regression analysis controlling for transplant era, pre-transplant dialysis > or = 6 months, maintenance mycophenolate mofetil (MMF) therapy, and allograft rejection, but not induction antibody therapy, were significantly associated with hospitalized CMV disease. Compared with recipients with negative CMV serology (R-) who had donor kidneys with negative CMV serology (D-), D+/R- had the highest risk of hospitalization for CMV disease [adjusted odds ratio (AOR) 5.19, 95% confidence interval (CI) 3.89-6.93] followed by D+/R+ recipients, whereas D-/R+ were not at significantly increased risk. In Cox Regression analysis the relative risk of death associated with hospitalized CMV disease was 1.32 (95% CI 1.02-1.71).
Conclusions: Even in modern era, renal transplant recipients were at high risk for hospitalizations for CMV disease, which were associated with decreased patient survival. Current prophylactic measures have apparently not reduced the high risk of D+/R- recipients. Prolonged pre-transplant dialysis and maintenance MMF should also be considered risk factors for hospitalized CMV infection, and prospective trials of prophylactic antiviral therapy should be performed in these subgroups.