Incidence of candidaemia and relationship with fluconazole use in an intensive care unit

Abstract

Candida spp. are the most important non-bacterial pathogens in critically ill patients. The aim of this study was to evaluate trends in the incidence of candidaemia and the distribution of Candida albicans and non-albicans over a 9 year period (1999-2007), and to assess their relationship with fluconazole use. This was an interventional cross-over study. Patients admitted to the intensive care unit (ICU) who developed a clinically and microbiologically documented candidaemia were analysed. Fluconazole was used as prophylaxis in critically ill patients until 2002; from January 2003 infectious disease consultants strongly discouraged its use. Fluconazole use, measured as defined daily dose per 1000 patient-days, was calculated. The main outcome of the study is the evaluation of the restriction policy in terms of change in fluconazole use and in incidence of candidaemia. During the 108 month period (January 1999-December 2007), a total of 213 episodes of candidaemia (average incidence 1.42 episodes/10 000 patient-days/year, range 0.36-3.02 episodes) were recorded in a mixed medical and surgical ICU in Italy. C. albicans was the most prevalent isolated species (n = 98, 46%); non-albicans (n = 115, 54%) were mainly represented by Candida parapsilosis (n = 46, 22%) and by Candida glabrata (n = 28, 13%). Segmented regression analysis of the interrupted time series showed that a change in the fluconazole prophylactic strategy resulted in a significant reduction in fluconazole use from the second semester of 2002. A dramatic decrease in the incidence of fungaemia due to C. non-albicans was observed from the second semester of 2003 (intervention effect in the second semester of 2007: -2.31/10 000 patient-days); minor changes in the incidence of C. albicans fungaemia emerged (intervention effect in the second semester of 2007: -0.23/10 000 patient-days). The study showed a clear correlation between fluconazole use control and decreasing incidence of non-albicans candidaemia. Even if fluconazole remains a first-line treatment option in several cases of invasive candidiasis, its prophylactic use should be carefully evaluated.