Candida tropicalis bloodstream infection: Incidence, risk factors and outcome in a population-based surveillance

Abstract

Objective: To assess the current clinical features and determinants of outcome of Candida tropicalis bloodstream infection (BSI).

Methods: A population-based surveillance on Candida BSI was conducted from May 2010 to April 2011 in 29 Spanish hospitals. Antifungal susceptibility testing (EUCAST methodology) was centrally performed. The characteristics and outcome of C. tropicalis BSI episodes were compared with those due to other species.

Results: Fifty-nine out of 752 episodes (7.8%) were due to C. tropicalis (annual incidence: 0.62 cases per 100,000 population). Resistance to fluconazole and voriconazole was found in 23.2% and 26.8% of isolates. Breakthrough BSI occurred in 10.5% of episodes. Risk factors for C. tropicalis BSI were age (odds ratio [OR]: 1.01; P-value = 0.05), underlying leukaemia (OR: 4.77; P-value = 0.001) and chronic lung disease (OR: 2.62; P-value = 0.002). There were no differences in clinical failure (persistent BSI for ≥72 h after initiation of therapy and/or 30-day all-cause mortality) between C. tropicalis (39.6%) and non-C. tropicalis groups (45.6%). The appropriateness of antifungal therapy or the fluconazole MIC values had no significant impact on outcome, whereas early central venous catheter removal exerted a protective effect.

Conclusions: C. tropicalis BSI was associated with advanced age, haematological malignancy and respiratory comorbidity. We found no correlation between the unexpectedly high resistance rate to azoles observed and outcome.

Keywords: Candida tropicalis bloodstream infection; Epidemiology; Minimum inhibitory concentration; Outcome; Treatment.