Fungal surveillance cultures during antifungal prophylaxis with itraconazole in neutropenic patients with acute leukaemia

Fungal colonization has been associated with an increased rate of invasive fungal infections in neutropenic patients. This study evaluates weekly fungal surveillance cultures from the oropharyngeal and perianal space as well as other suspected sites in 219 courses of myelosuppressive chemotherapy with itraconazole antifungal prophylaxis in 116 neutropenic patients with acute leukaemia. Itraconazole was given from the start of chemotherapy in one of six different dosing regimens. Fungal colonization occurred in 68 (31%) of courses, which was lower than in a historical control group without prophylaxis (53%, P=0.004). Twenty-six per cent of these 116 isolates had a growth rate of more than 50 colony forming units (CFU) per culture. Candida glabrata (51%), Candida albicans (18%) and Candida krusei (4%) were the most frequently isolated species. Higher median itraconazole trough concentrations were associated with a lower growth rate in the cultures (less than or equal to 50 CFU/culture versus>50 CFU/culture): 710 (430-1180) ng ml(-1) versus 900 (560-1650) ng ml(-1) (P=0.015). The use of itraconazole solution-compared with capsules-led to a reduced growth rate (P=0.035). In conclusion, compared with historical controls itraconazole antifungal prophylaxis reduces the incidence and the extent of fungal colonization during neutropenia in patients with acute leukaemia.