Invasive fungal infections in allogeneic and autologous stem cell transplant recipients: a single-center study of 166 transplanted patients.

OBJECTIVES

Invasive fungal infections (IFIs) remain a major cause of infection-related morbidity and mortality following hematopoietic stem cell transplantation (HSCT).

PATIENTS AND METHODS

We retrospectively analyzed the incidence of IFIs in 166 patients undergoing either allogeneic or autologous HSCT at our institution between January 2000 and December 2003.

RESULTS

Incidence of invasive aspergillosis (IA) and invasive candidiasis among allogeneic HSCT recipients was 23% (16-32%, 95% confidence interval [CI]) and 3% (1-9%, 95% CI), respectively. Duration of neutropenia and reduced-intensity conditioning were the only risk factors for IA in the multivariate model. Patients with IA had significantly reduced overall survival (8% versus 56%, P=0.01) due to higher transplant-related mortality (63% versus 31%, P=0.03). Following autologous HSCT, incidence of IA and invasive candidiasis was 8% (4-19%, 95% CI) and 2% (0.2-11%, 95% CI), respectively. Duration of neutropenia was the only risk factor for the development of IA following autologous HSCT. Overall survival of autologous HSCT recipients with IA was similar to that of patients without IA. Seventeen percent of autologous HSCT recipients were colonized with Candida species. Compared with non-colonized patients these patients had significantly reduced overall survival (72% versus 23%, P=0.004), due to increased treatment-related mortality (23% versus 9%, P=0.02).

CONCLUSION

Diagnosis of IA following allogeneic HSCT and Candida colonization in the setting of autologous HSCT defines patient populations with poor outcome but primarily not as a result of the fungal pathogen. Regarding the incidence of IA, duration of neutropenia is the main risk factor, and dose-reduced conditioning is an additional risk factor for the development of IA following allogeneic HSCT, probably owing to increased recipient age in this patient cohort, requiring further studies in this transplantation setting.