Species distribution and susceptibility profile to fluconazole, voriconazole and MXP-4509 of 551 clinical yeast isolates from a Romanian multi-centre study

Abstract

This is the first multi-centre study regarding yeast infections in Romania. The aim was to determine the aetiological spectrum and susceptibility pattern to fluconazole, voriconazole and the novel compound MXP-4509. The 551 isolates were identified using routine laboratory methods, matrix-assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF MS) and DNA sequence analysis. Susceptibility testing was performed using the European Committee for Antimicrobial Susceptibility Testing (EUCAST) method and breakpoints. The yeasts originated from superficial infections (SUP, 51.5 %), bloodstream infections (BSI, 31.6 %) and deep-seated infections (DEEP, 16.9 %), from patients of all ages. Nine genera and 30 species were identified. The 20 Candida species accounted for 94.6 % of all isolates. C. albicans was the overall leading pathogen (50.5 %). Lodderomyces elongisporus is reported for the first time as a fungaemia cause in Europe. C. glabrata and Saccharomyces cerevisiae, as well as the non-Candida spp. and non-albicans Candida spp. groups, showed decreased fluconazole susceptibility (<75 %). The overall fluconazole resistance was 10.2 %. C. krusei accounted for 27 of the 56 fluconazole-resistant isolates. The overall voriconazole resistance was 2.5 % and was due mainly to C. glabrata and C. tropicalis isolates. Fluconazole resistance rates for the three categories of infection were similar to the overall value; voriconazole resistance rates differed: 4 % for BSI, 3.2 % for DEEP and 1.4 % for SUP. The antifungal activity of MXP-4509 was superior to voriconazole against C. glabrata and many fluconazole-resistant isolates. There was a large percentage of non-albicans Candida isolates. A large part of the high fluconazole resistance was not acquired but intrinsic, resulting from the high percentage of C. krusei.

In Vitro Antifungal Susceptibility Testing of Candida Isolates with the EUCAST Methodology, a New Method for ECOFF Determination

“…These rates are comparable with those from previously published epidemiological studies, but with notable differences (8)(9)(10)(11)(12). Higher rates of resistance for C. tropicalis to voriconazole (25 to 67%) and of different Candida species to posaconazole (18 to 80%) were previously reported using smaller collections of bloodstream isolates (n Ͻ60) and a lower breakpoint of 0.06 mg/liter for posaconazole compared with that in the present study (8,9,11).…”

Outbreak of candidemia caused by fluconazole resistant Candida parapsilosis strains in an intensive care unit

“…In accordance with recent studies, using antifungal susceptibility tests that are considered gold standards (CLSI and EUCAST- European committee on Antimicrobial Susceptibility Testing, microbroth assays), the rates of fluconazole resistance in blood stream C. parapsilosis isolates ranges from 3.4 to 7.5 % in the USA [17, 25, 26], 0 to 6.3 % in Europe and up to 5.4 in Asia [17, 27, 28]. …”

Notable Increasing Trend in Azole Non-susceptible Candida tropicalis Causing Invasive Candidiasis in China (August 2009 to July 2014): Molecular Epidemiology and Clinical Azole Consumption

“…Although there is a general consensus worldwide that C. tropicalis strains exhibit a moderate level of azole resistance (Kothavade et al, 2010; Jiang et al, 2013; Guinea et al, 2014), it is important to note that the rates of C. tropicalis resistance to azoles in North America and most European countries are low. For example, C. tropicalis resistant rates to fluconazole in the United States are generally <7% (Lockhart et al, 2012; Pfaller et al, 2015), whilst those reported in European countries vary from 0 to 12% (Orasch et al, 2014; Minea et al, 2015; Posteraro et al, 2015; Tadec et al, 2016). …”