Candida species are opportunistic yeasts that can be a serious threat for immunocompromised and critically ill patients, and a cause for increased morbidity and mortality in hospitalized patients. The aim of this study was to determine the frequency and distribution of different Candida species in clinical specimens in patients with increased risk for fungal infections, and to determine the antifungal susceptibility profile of invasive Candida species to antifungal agents. During a two year period, clinical specimens from 120 patients divided into 4 groups were analysed at the Institute of microbiology and parasitology, Faculty of Medicine, Skopje, Republic of Macedonia. Each of these 4 groups consisted of specimens from 30 patients, with primary immune deficiency, critically ill patients treated in the intensive care units (ICU), patients with mucosal candidiasis only, and patients with cystic fibrosis. All specimens were investigated with conventional mycological methods. Identification of Candida species was performed with VITEK-2 system (bioMérieux, France). E-test strips of fluconazole, voriconazole, amphotericin B and caspofungin (AB bioMerieux, France) were used for determination of the antifungal susceptibility profile. In this study, a total of 115 isolates of Candida species were confirmed in different clinical specimens (91 isolates from mucosal surfaces and 24 isolates from blood culture). Colonisation of mucosal membranes of gastrointestinal, respiratory and/or urinary tracts was registered in 56.67% (17/30), 56.67% (17/30), 90% (27/30) and 100% (30/30) of the specimens in the first, second, third and fourth group respectively. In all four groups of patients, the following Candida species were confirmed: C. albicans - 55%, C. glabrata - 17.6%, C.
parapsilosis - 7.7%, C. tropicalis - 6.6%, unidentified Candida species - 4.4%, C. dubliniensis - 3.3%, C. kefyr - 2.2%, and one isolate of C. rugosa, C. pelliculosa and C. krusei each. Positive blood culture was registered in 23.33% specimens from the first group, 43.33% in the second group, 23.08% of the third group, and in one specimen of the fourth group. The most frequent isolates from blood culture were C. tropicalis and C. krusei, followed by C. albicans, C. parapsilosis and C. tropicalis, and in the second group C. albicans and C. pelliculosa were equally distributed, followed by C. parapsilosis and C. glabrata. All invasive isolates of Candida species were susceptible to
amphotericin B, voriconazole and caspofungin. Resistance to fluconazole was registered in 8.3% (2/24) of all confirmed Candida species. Dose-dependent susceptibility to fluconazole was confirmed in 46% (11/24) of the isolates. Our study confirms high prevalence of colonisation and candidemia with non-albicans Candida species. Resistance to antifungal agents was registered only in two isolates of C. krusei. An epidemiological study is necessary for surveillance of dynamics of candidemia and antifungal susceptibility profile of invasive isolates of Candida species in our patients.
Candida Species in Blood Culture and Antifungal Susceptibility Profile
