Risk factors for invasive aspergillosis in acute myeloid leukemia patients prophylactically treated with posaconazole

Invasive aspergillosis (IA) is an important cause of morbidity and mortality in neutropenic patients with hematological malignancies. To investigate the immediate and mid-term benefits of posaconazole prophylaxis in AML patients undergoing first induction chemotherapy and to study the infection risk factors, we prospectively studied the IA incidence in these patients at our hospital between years 2007 and 2008; then we compared them to a matched control group without prophylaxis. There were 55 and 66 patients in each group respectively. At day 32 post-induction, two probable cases (3.6%) were scored in the prophylaxis group compared to 8 cases (12.1%) in the control group (4 possible and 4 probable). At day 100, it reached 7.27% and 15.5% respectively. Kaplan-Meier analysis at day 100 showed lower mortality rate in the prophylaxis group compared to the control group [3.64% (n = 2, none due to IA) and 10.61% (n = 7, four due to IA) respectively, P = 0.002]. Multivariate analysis showed age and lack of response to induction as independent infection risk factors. Posaconazole prophylaxis resulted in lower incidence of IA and significantly improved survival. Patient's age and response to induction treatment are two independent infection risk factors, and need more attention during future clinical trials linked to antifungal prophylaxis.