Background: The purpose of our study was to evaluate the incidence and outcome of invasive fungal infection (IFI) among patients who underwent autologous or allogeneic hematopoietic stem cell transplantation (HSCT) at 11 Italian transplantation centers.
Methods: This cohort-retrospective study, conducted during 1999-2003, involved HSCT patients admitted to 11 tertiary care centers or university hospitals in Italy, who developed IFIs (proven or probable).
Results: Among 3228 patients who underwent HSCT (1249 allogeneic HSCT recipients and 1979 autologous HSCT recipients), IFI occurred in 121 patients (overall incidence, 3.7%). Ninety-one episodes (2.8% of all patients) were due to molds, and 30 (0.9%) were due to yeasts. Ninety-eight episodes (7.8%) occurred among the 1249 allogeneic HSCT recipients, and 23 (1.2%) occurred among the 1979 autologous HSCT recipients. The most frequent etiological agents were Aspergillus species (86 episodes) and Candida species (30 episodes). The overall mortality rate was 5.7% among allogeneic HSCT recipients and 0.4% among autologous HSCT recipients, whereas the attributable mortality rate registered in our population was 65.3% (72.4% for allogeneic HSCT recipients and 34.7% for autologous HSCT recipients). Etiology influenced the patients' outcomes: the attributable mortality rate for aspergillosis was 72.1% (77.2% and 14.3% for allogeneic and autologous HSCT recipients, respectively), and the rate for Candida IFI was 50% (57.1% and 43.8% for allogeneic and autologous HSCT recipients, respectively).
Conclusions: IFI represents a common complication for allogeneic HSCT recipients. Aspergillus species is the most frequently detected agent in these patients, and aspergillosis is characterized by a high mortality rate. Conversely, autologous HSCT recipients rarely develop aspergillosis, and the attributable mortality rate is markedly lower. Candidemia was observed less often than aspergillosis among both allogeneic and autologous HSCT recipients; furthermore, there was no difference in either the incidence of or the attributable mortality rate for candidemia among recipients of the 2 transplant types.