Background.  Transplant recipients are at risk for invasive aspergillosis (IA), associated with a significant mortality rate. Renal transplant–specific risk factors have not been established.

Methods.  Forty-one adult kidney transplant recipients diagnosed with proven or probable IA from 1995 through 2013 were identified by search of the computerized patient files in the University Hospitals Leuven. The control population in this 1:2 case-control study consisted of the 2 patients who received a kidney transplant immediately before and after each identified patient and did not develop IA (n = 82).

Results.  Leukopenia after kidney transplant increased the risk of IA among all patients (odds ratio [OR], 2.345 [95% confidence interval {CI}, 1.084–5.071]). For early-onset infection (ie, occurred during the first 3 months after transplant), a longer duration of renal replacement therapy pretransplant and the occurrence of leukopenia were risk factors (OR per year, 1.192 [95% CI, 1.006–1.413] and OR, 3.346 [95% CI, 1.063–10.527], respectively), whereas donor cytomegalovirus seropositivity increased the risk for late-onset IA (ie, occurred >3 months after transplant) (OR, 3.677 [95% CI, 1.388–9.743]). Twelve-week mortality rate was 39%. Disseminated infection, leukopenia, and the height of the serum galactomannan index were associated with an increased risk of death (hazard ratio [HR], 5.080 [95% CI, 1.740–14.830]; HR, 3.198 [95% CI, 1.183–8.649]; and HR, 1.371 [95% CI, 1.123–1.674], respectively).

Conclusions.  Prolonged renal replacement therapy before kidney transplant increases the risk of IA early after transplant. The height of the serum galactomannan index predicts mortality.