Survey of Vaginal-Flora Candida Species Isolates from Women of Different Age Groups by Use of Species-Specific PCR Detection

Abstract

A retrospective survey of 93,775 samples testing positive in Candida species-specific PCR tests performed on cervicovaginal swabs over a 4-year period demonstrated consistent yearly distributions of Candida albicans (89%), C. glabrata (7.9%), C. parapsilosis (1.7%), and C. tropicalis (1.4%). However, the species distributions among different age groups revealed increases in the percentages of non-albicans species with increases in age.Vulvovaginal candidiasis (VVC) is a common fungal infection that affects healthy women of all ages. At least 75% of women will develop one or more infections once during their lifetime, with 5 to 8% of those individuals developing recurrent infections (5, 7). Current literature examining the species distribution of Candida isolates involved in VVC is limited; however, several important observations have been made. For example, one study shows that Candida albicans accounts for 70 to 90% of all VVC cases, with a recent emergence of nonalbicans species (10). The rise in VVC infections, more specifically in those caused by non-albicans species, could be due to several factors, ranging from an increase in over-the-counter antifungal use to an increase in high-risk patient populations (i.e., diabetics and menopausal women). Candida glabrata is the primary non-albicans species emerging in VVC, accounting for up to 14% of infections in immune-competent women (9, 10).In addition to an increase in non-albicans species overall, it is becoming clear that certain patient populations may experience higher risks of infection from these non-albicans species, often leading to limited treatment options. Interestingly, in a few small studies, C. glabrata was found to be the primary species isolated from diabetic (61.3%) and elderly (51.2%) patients with VVC (2, 4, 6, 11). Often, these non-albicans species are associated with elevated MIC levels for the azoles, the most commonly prescribed class of antifungal drugs. It has been well documented that C. glabrata demonstrates both intrinsically low susceptibility to the azoles and the ability to develop frank resistance (8,12,13,14,15,16). Moreover, a recent increase in the trailing phenotype, with low-level resistance to the azoles, has been observed for the Candida tropicalis isolates (1, 3). This highlights the importance of identifying Candida species within clinical samples in order to provide physicians with information concerning the proper treatment for their patients.

Colonization byCandidaSpecies of the Oral and Vaginal Mucosa in HIV-Infected and Noninfected Women

“…12 Carrier rates of Candida ranging from 17% to 75% have been reported, depending on the population studied. 13 However, we found substantial rates of both in our cohorts.…”

Advanced topical drug delivery system for the management of vaginal candidiasis

“…among which C. glabrata was the dominant one. Increase in number of C. glabrata was also observed in elderly diabetic patients (Vermitsky et al, 2008). This can be justified, as continuous use of azole agents leads to development of resistance in C. glabrata, which is characterized by higher colonization of C. glabrata in vaginal epithelium as compared to C. albicans.…”

“…should be done. Non-azole anti-fungal drugs like Boric acid and Flucytosine can be used for non-albicans species (Ogunshe et al, 2008;Vermitsky et al, 2008;Abruquah, 2012).…”

Identificação por PCR e sensibilidade a antifúngicos de isolados clínicos vaginais de Candida sp

“…Entretanto, o uso destes testes na rotina laboratorial não é comum, pois estas técnicas apresentam custo elevado o que limita sua realização. Uma alternativa seria a utilização dos testes de disco difusão e o E-teste para rastreamento, sendo os métodos de diluição em caldo reservados para confirmação de resistência 36 . Outro fato importante a ser destacado é o crescente aumento do número de isolados de espécies não-albicans, e a dificuldade e imprecisão dos testes fenotípicos na determinação destas espécies, assim abordagens moleculares estão sendo desenvolvidas para estabelecer uma identificação mais rápida e segura de espécies de fungos 13 .…”