Intra-abdominal candidiasis in surgical intensive care unit - epidemiology characteristics and trends

Intra-abdominal candidiasis (IAC) is an invasive fungal infection representing the most common type of invasive Candida infection in surgical intensive care units (ICUs). Recently, decreased antifungal susceptibility and progressive shift in the aetiology of invasive candidiasis has been observed worldwide. We explored IAC epidemiology in surgical ICU.

We retrospectively reviewed the records of 64 patients with IAC admitted at our surgical ICU over a 4-year period (2013-2016). IAC incidence, microbiological results, antifungal therapy, and mortality were analysed.

The cumulative IAC incidence was 18.4 cases per 1000 admissions (2013: 12.6; 2014: 17.7; 2015: 16.8; 2016: 24.5), including hospital-acquired IAC incidence (2013: 9.8; 2014: 13.3; 2015 10.1; 2016: 13.3) and community-acquired IAC incidence (2013: 2.8; 2014: 4.4; 2015: 6.7; 2016: 11.2). Candida albicans represented the most common species (n = 35, 50.0%) followed by Candida glabrata (n = 15, 21.4%), Candida tropicalis (n = 6, 8.6%) and other yeasts (each < 5.0%). Incidence rate of C. albicans (2013: 7(78%); 2014: 10(59%); 2015: 6(35%); 2016: 12(44%)) and incidence rate of C. non-albicans (2013: 2(22%); 2014: 7(41%); 2015: 9(53%); 2016: 14(52%)) were different in trend. All fungal isolates were susceptible to echinocandins, amphotericin B and voriconazole. Regarding fluconazole susceptibility, C. krusei (n = 3) was resistant and C. glabrata (n = 9) was susceptible-dose dependent (SDD). The ratio of SDD C. glabrata isolates to all isolated C. glabrata strains was 9/15 (60%) (2013: 0/2; 2014: 0/2; 2015: 1/3; 2016: 8/8). Decreased fluconazole susceptibility for C. glabrata isolates was reported in both community-acquired IAC (n = 3) and hospital-acquired IAC (n = 6). Overall 30-day mortality rate was 25.0% (16/64).

We have revealed slowly raising of overall IAC incidence, more increasing trend in incidence of community-acquired IAC compared to rather steady incidence of hospital-acquired IAC. During period 2013-2016 we have observed a significant shift in the aetiology of IAC towards an increased proportion of non-albicans Candida species, particularly C. glabrata. Acquired decreased fluconazole susceptibility was related to C. glabrata isolates exclusively. Emergence of decreased antifungal susceptibility has been preceded by increase of non-albicans Candida isolates.