Species distribution and susceptibility of Candida isolates from patient with vulvovaginal candidiasis in Southern China from 2003 to 2012

Genital-oral transmission of Candida lusitaniae

Candida lusitaniae is a vaginal commensal. Cases of vaginitis, vulvovaginitis and recurrent vulvovaginitis caused by this yeast are very rare. In the oral cavity, C. lusitaniae causes stomatitis in immunocompromised patients. We describe a case of stomatitis and angular cheilitis caused by C. lusitaniae in a female patient with type 2 diabetes. The infection was most likely transmitted following genital-oral intercourse with the patient's girlfriend, who was affected by C. lusitaniae vulvovaginitis.

In Vitro Antifungal Activity of Azoles and Other Antifungal Agents Against Pathogenic Yeasts from Vulvovaginal Candidiasis in China

BACKGROUND

Vulvovaginal candidiasis (VVC) is a public health issue worldwide. Little is known of the optimal treatment of recurrent VVC (RVVC) has not been established.

OBJECTIVE

Through the in vitro antifungal susceptibility profiling of VVC isolates, we hope to foster significant improvements in the control and treatment of this disease.

METHODS

Candida isolates from VVC patients were collected from 12 hospitals in 10 cities across China. Species were identified by phenotype analysis and DNA sequencing. Species were identified by phenotype analysis and DNA sequencing. Susceptibilities to 11 drugs were determined by Clinical and Laboratory Standards Institute broth microdilution.

RESULTS

543 strains were isolated from those VVC patients enrolled in this study, of which, 15.7% were from RVVC. The most commonly identified species was C. albicans (460, 84.71%), and the most commonly non-albicans Candida spp. (NAC) was C. glabrata (47, 8.66%). NAC also included C. Krusei, Meyerozyma Guillermondii, Meyerozyma Caribbica, C. Tropicalis, C. Parapsilosis, and C. Nivariensis. Most C. albicans isolates were susceptible to caspofungin (99.8%), followed by fluconazole (92%) and voriconazole (82.6%). The proportion of C. albicans strains with wild type (WT) MICs that were susceptible to amphotericin B and caspofungin were 98%, followed by posaconazole at 95%, itraconazole at 86%, fluconazole at 74% and voriconazole at 54%. The fluconazole MICs for C. albicans were lower than those for NAC (P < 0.05), while the itraconazole MICs showing no significant difference (P > 0.05). The susceptible rate of uncomplicated VVC to fluconazole was 92%. The proportion of WT strains to fluconazole in RVVC was much lower than that in other types of VVC (67 vs. 77%, P < 0.05). However, the proportions of WT strains to itraconazole in RVVC was over 85%, which was much higher than that to fluconazole (87 vs. 67%, P < 0.05).

CONCLUSIONS

C. albicans was still the predominant pathogen for VVC in China, while C. glabrata was the main species in NAC. Fluconazole could still be used as an empirical treatment for uncomplicated VVC. However, fluconazole may not be the first choice for the therapy of RVVC. In such cases, itraconazole appears to be the more appropriate treatment. As for VVC caused by NAC, nonfluconazole drugs, such as itraconazole, may be a good choice.

Distribution and antifungal susceptibility pattern of Candida species from mainland China: A systematic analysis

Antifungal resistance to Candida pathogens increases morbidity and mortality of immunosuppressive patients, an emerging crisis worldwide. Understanding the Candida prevalence and antifungal susceptibility pattern is necessary to control and treat candidiasis. We aimed to systematically analyse the susceptibility profiles of Candida species published in the last ten years (December 2011 to December 2021) from mainland China. The studies were collected from PubMed, Google Scholar, and Science Direct search engines. Out of 89 included studies, a total of 44,716 Candida isolates were collected, mainly comprising C. albicans (49.36%), C. tropicalis (21.89%), C. parapsilosis (13.92%), and C. glabrata (11.37%). The lowest susceptibility was detected for azole group; fluconazole susceptibilities against C. parapsilosis, C. albicans, C. glabrata, C. tropicalis, C. guilliermondii, C. pelliculosa, and C. auris were 93.25%, 91.6%, 79.4%, 77.95%, 76%, 50%, and 0% respectively. Amphotericin B and anidulafungin were the most susceptible drugs for all Candida species. Resistance to azole was mainly linked with mutations in ERG11, ERG3, ERG4, MRR1-2, MSH-2, and PDR-1 genes. Mutation in FKS-1 and FKS-2 in C. auris and C. glabrata causing resistance to echinocandins was stated in two studies. Gaps in the studies' characteristics were detected, such as 79.77%, 47.19 %, 26.97%, 7.86%, and 4.49% studies did not mention the mortality rates, age, gender, breakpoint reference guidelines, and fungal identification method, respectively. The current study demonstrates the overall antifungal susceptibility pattern of Candida species, gaps in surveillance studies and risk-reduction strategies that could be supportive in candidiasis therapy and for the researchers in their future studies.

Prevalence and species distribution of microorganisms isolated among non-pregnant women affected by vulvovaginal candidiasis: A retrospective study over a 20 year-period

BACKGROUND

Vulvovaginal candidiasis (VVC) is the second most common infection of the genital tract affecting millions of women worldwide. Data concerning the distribution and antifungal resistance of Candida species responsible of VVC vary among countries and population studied.

OBJECTIVES

The aim of this work was to determine the prevalence, species distribution and antifungal susceptibility patterns of Candida species among symptomatic women over a 20-year period.

METHODS

A total of 5,820 unique samples were retrospectively identified. Out of them, 1,046 (18%) were diagnosed with VVC.

RESULTS

Women between 18 and 30 years had the highest prevalence rate of VVC (21%). Women aged less than 18 years and greater than 51 years had the highest prevalence rates of vaginal bacterial infections. Thirty-five (3.3%) women presented recurrent VVC. The most common yeast isolated was C. albicans, followed by C. glabrata, C. krusei, and C. parapsilosis. Non-Candida albicans species (NAC) were more significantly isolated among women aged 51 or above, than in women included in other groups (p < 0.01). Resistance to fluconazole and amphotericin B was infrequent in C. albicans strains. Resistance to fluconazole and amphotericin B was infrequent in C. albicans strains. NAC species presented higher resistance rates against fluconazole (30%) and voriconazole (25%). C. krusei and C. glabrata isolates showed lower MICs than most of the strains against amphotericin B (1 mg/L) and flucytosine (1 mg/L).

CONCLUSIONS

Our findings indicated that continued surveillance on Candida species distribution and non-susceptibility rates to antifungals should be routinely reported to help the selection of the most appropriate drug, to avoid the emergence of resistant strains, and to improve the patient's outcomes.

Genotyping and Drug Resistance Profile of Clinical Isolates of Candida albicans from Vulvovaginal Candidiasis in the Eastern China

A total of 244 Candida albicans isolates recovered from vulvovaginal candidiasis (VVC) patients in Suzhou, Eastern China, were investigated. According to CLSI documents M27-A4 and M59-3ed/M60-2ed, the MIC geometric means of nine antifungals in increasing order were micafungin (0.048 mg/L), anidulafungin (0.132 mg/L), caspofungin (0.19 mg/L), itraconazole (0.23 mg/L), posaconazole (0.25 mg/L), voriconazole (0.28 mg/L), 5-flucytosine (0.44 mg/L), amphotericin B (0.49 mg/L) and fluconazole (2.01 mg/L) respectively. Of note, 6.5% (16/244) C. albicans isolates showed resistance mainly to anidulafungin (mono-echinocandin resistance), while voriconazole had the lowest susceptibility rate of 34.8% (85/244), followed by fluconazole 59.4% (145/244), respectively. All isolates were genotyped by allelic combination of 3 microsatellite markers (CEF3, CAIII and LOC4). A total of 129 different allelic genotypes were identified, in which seven different clades were recognized with a discriminatory power of 0.96. Genotypes A-D were present in 35% of the isolates. In conclusion, decrease in antifungal drug susceptibility to C. albicans isolates from VVC is alarming. Our findings revealed the genetic diversity of C. albicans isolates among VVC patients and provided insights into the molecular epidemiology of Candida infections in China.

Prevalence, species distribution and antifungal susceptibility of Candida albicans causing vaginal discharge among symptomatic non-pregnant women of reproductive age at a tertiary care hospital, Vietnam

Background

Vaginal candidiasis is frequent in women of reproductive age. Accurate identification Candida provides helpful information for successful therapy and epidemiology study; however, there are very limited data from the Vietnam have been reported. This study was performed to determine the prevalence, species distribution of yeast causing vaginal discharge and antifungal susceptibility patterns of Candida albicans among symptomatic non-pregnant women of reproductive age.

Methods

Vaginal discharge samples were collected from 462 women of reproductive age in Hanoi, Vietnam between Sep 2019 and Oct 2020. Vaginal swabs from these patients were examined by direct microscopic examination (10% KOH). CHROMagar™ Candida medium and Sabouraud dextrose agar supplemented with chloramphenicol (0.5 g/l) were used to isolate yeast, and species identification was performed using morphological tests and molecular tools (PCR and sequencing). Antifungal susceptibility testing was determined according to the Clinical and Laboratory Standards Institute guidelines (M27-A3 and M27-S4).

Results

The prevalence of vaginal yeast colonization in non-pregnant women was 51.3% of 462 participants. Nine different yeast species were identified. Among these isolates, C. albicans (51.37%) was the most frequent, followed by C. parapsilosis (25.88%), C. glabrata (11.37%), C. tropicalis (4.31%), C. krusei (3.92%), C. africana (1.57%), Saccharomyces cerevisiae (0.78%), C. nivariensis (1 isolates, 0.39%), and C. lusitaniae (1 isolates, 0.39%), respectively. Among C. albicans, all 46 isolates were 100% susceptible to micafungin, caspofungin, and miconazole. The susceptibility rates to amphotericine B, 5-flucytosine, fluconazole, itraconazole and voriconazole were 95.65, 91.30, 91.30, 82.61 and 86.95%, respectively.

Conclusions

The prevalence of VVC among symptomatic non-pregnant women of reproductive age in Vietnam was higher than many parts of the world. The high frequency of non-albicans Candida species, which were often more resistant to antifungal agents, was a notable feature. Resistance rates of vaginal C. albicans isolates to antifungal agents was low. Our findings suggest that continued surveillance of changes in species distribution and susceptibility to antifungals should be routinely screened and treated.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-06192-7.

Chronic recurrent vulvovaginitis is not only due to Candida

BACKGROUND

Recurrent vulvovaginitis is a growing problem that affects millions of women worldwide. In many cases it is treated as vulvovaginal candidiasis, but there is not always microbiological confirmation.

AIMS

To determine the etiology of vulvovaginitis in a group of patients.

METHODS

This is a cross-sectional study in which the data from the medical records of 316 adult patients who consulted for vulvovaginitis were analyzed. Eighty nine percent of the cases had already suffered previous episodes.

RESULTS

The median age was 34 (265 patients were between 16 and 45 years old). Yeasts were isolated in culture from 211 (66.8%) patients, although pseudo-hyphae and yeasts were observed in only 166 samples (52.5%) in the direct microscopic examination. Multiple predisposing factors were found, among which the use of contraceptives or previous antibiotics stand out. Most of the patients (almost 90%) had been treated with antifungals, with or without microbiological confirmation. Candida albicans was isolated in 187 (88.6%) patients, followed by Candida glabrata in 6 (2.8%) patients. Association with bacterial vaginosis was found in 35.1% and with intermediate bacterial microbiota in 33.2% of the cases. A remarkably high proportion of C. albicans isolates resistant to fluconazole (80.1%) and itraconazole (58.8%) was found.

CONCLUSIONS

A microbiological analysis is essential to confirm the diagnosis of vulvovaginal candidiasis, whether simple, complicated, or recurrent. Identifying the isolated yeast species and determining its susceptibility to antifungal agents are particularly important.

Recurrent Vulvovaginal Candidosis and Cluster Analysis of Clinical Signs and Symptoms: A Laboratory-Based Investigation

Recurrent vulvovaginal candidosis (RVVC) represents a major health problem that significantly affects a patient’s quality of life (QoL). This infection presents with a plethora of clinical manifestation, and this is the first study that carries out a cluster analysis of these signs and symptoms (SS). The goals are to evaluate the distribution of species causing RVVC, their in-vitro susceptibility to antifungals, and the patient’s QoL. Additionally, the clinical characteristics are analyzed using cluster analysis. Prospective analysis of data was performed for women diagnosed with RVVC in the period from January 2016 to December 2019 based on the analysis of data from a single-center’s records. The standard mycological methods and antifungal susceptibility testing were done. Clinical characteristics and QoL were examined by appropriate questions. The cluster analysis was used to identify clusters of SS. A total of 320 women were diagnosed. The dominant species was Candida (C.) albicans. Non-albicans Candida (NAC) yeast was found in 24.4%, and the most common was C. glabrata. Interestingly, Saccharomyces (S.) cerevisiae was detected in 2%. All of the isolated species, except C. parapsilosis and C. kefyr, demonstrated reduced susceptibility to antifungals. We confirmed the emergence of the NAC species and S. cerevisiae with reduced susceptibility to antifungals. Cluster analysis represented by a dendrogram revealed three SS clusters: irritation, uncommon, and discharge, but further studies are needed to examine the relationship between clusters, Candida strains, and outcomes.

Biofilm Formation of Candida albicans Facilitates Fungal Infiltration and Persister Cell Formation in Vaginal Candidiasis

Background

Vaginal candidiasis is an important medical condition awaiting more effective treatment. How Candida albicans causes this disease and survives antifungal treatment is not yet fully understood. This study aimed to establish a comprehensive understanding of biofilm-related defensive strategies that C. albicans uses to establish vaginal candidiasis and to survive antifungal treatment.

Methods

A mouse model of vaginal candidiasis was adopted to examine the formation of biotic biofilms on the vaginal epithelium and fungal infiltration by laboratory and clinical strains of C. albicans. Histopathological changes and local inflammation in the vaginal epithelium caused by C. albicans of different biofilm phenotypes were compared. Antifungal susceptibility testing was carried out for C. albicans grown as planktonic cells, microplate-based abiotic biofilms, and epithelium-based biotic biofilms. Formation of persister cells by C. albicans in different growth modes was also quantified and compared.

Results

C. albicans wild-type reference strains and clinical isolates, but not the biofilm-defective mutants, formed a significant number of biotic biofilms on the vaginal epithelium of mice and infiltrated the epithelium. Biofilm formation and epithelial invasion induced local inflammatory responses and histopathological changes in the vaginal epithelium including neutrophil infiltration and subcorneal microabscesses. Biofilm growth on the vaginal epithelium also led to high resistance to antifungal treatments and promoted the formation of antifungal-tolerant persister cells.

Conclusion

This study comprehensively assessed biofilm-related microbial strategies that C. albicans uses in vaginal candidiasis and provided experimental evidence to support the important role of biofilm formation in the histopathogenesis of vaginal candidiasis and the recalcitrance of the infection to antifungal treatment.

Prevalence of vulvovaginal candidiasis among pregnant women in the Ho municipality, Ghana: species identification and antifungal susceptibility of Candida isolates

Background

Candida is the leading cause of vaginitis, and 75% of women have at least one episode of infection in their lives, with pregnancy being a predisposing factor. If left untreated, vulvovaginal candidiasis (VVC) can lead to chorioamnionitis with subsequent abortion, prematurity and congenital infection of the neonate. We aimed to determine the prevalence of VVC, identify the recent and most frequently occurring species of Candida in pregnant women, and determine the most effective antifungal drug of choice for treatment.

Method

A prospective cross-sectional study in which 176 high vaginal swab samples of consented pregnant women visiting the antenatal clinic from February 2018 to April 2018 were subjected to direct gram smear and culture for Candida isolation. Candida isolates were identified using a germ tube test and HiCrome Candida differential agar. Candida isolates were then subjected to a disk diffusion method using fluconazole (25 μg), nystatin (100 units), and voriconazole (1 μg) on Mueller-Hinton agar supplemented with 2% (w/v) glucose and 0.5 μg/ml methylene blue dye to determine the susceptibility pattern as per the guidelines of the Clinical Laboratory Standard Institute (CLSI). Chi-square analysis was used to ascertain the significant association of participants’ sociodemographics and clinical presentations to VVC. A univariate logistic regression model was used to identify potential risk factors of VVC.

Results

The prevalence of VVC among our study participants was 30.7%. Non-albicans Candida (NAC) and Candida albicans had a prevalence of 74.1 and 25.9%, respectively. Candida glabrata was the most common species, followed by Candida albicans, Candida krusei, and Candida parapsilosis. 50.0, 18.5 and 3.7% of Candida species were susceptible to voriconazole, fluconazole and nystatin, respectively, whereas 37.0, 48.1 and 9.3% of Candida species were resistant to voriconazole, fluconazole and nystatin, respectively. The majority of isolates were susceptible dose dependent to all three antifungal agents, with voriconazole being the most efficacious antifungal agent. There was no significant association between participants’ socio-demographic information and clinical presentations to VVC.

Conclusion

The prevalence of VVC was high in the study area. C. glabrata was found to be the most common cause of VVC among the pregnant women attending antenatal clinics, in the Ho Municipality region of Ghana. The majority of the Candida isolates were susceptible and resistant to voriconazole and fluconazole, respectively.

Molecular identification and antifungal susceptibility profile of yeast from vulvovaginal candidiasis

BACKGROUND

Accurate identification Candida is important for successful therapy and epidemiology study. The aim of research is to study API 20C yeast identification system identification rate by using molecular identification as gold standard and tested the antifungal susceptibility of Candida from patients with vulvovaginal candidiasis (VVC).

METHODS

In total, 3574 yeast isolates were obtained from patients with VVC. API 20C yeast identification, molecular identification and in vitro antifungal susceptibility were performed.

RESULTS

C. albicans was the predominant Candida species [2748 isolates, 76.9%] in VVC. The isolates from vaginal samples represented 22 species based on molecular identification. The API 20C system identifies only 11 of the species encountered during the study period. Based on the API 20C system, 3273 (91.78%) isolates were correctly identified to the species level. The correct identification rate of the API 20C system for rare yeast was 15.29% (26/170 isolates). Antifungal susceptibility was tested in a total of 1844 isolates of Candida from patients with VVC. C. albicans was susceptible to most of the tested antifungals. The MICs of azoles for C. glabrata were higher than those for C. albicans. The MICs of echinocandins for C. parapsilosis were higher than those for C. albicans.

CONCLUSIONS

The API 20C yeast identification system can be used to reliably identify the most common Candida species while molecular methods are necessary for the identification of closely related, emerging, and rare yeast species. The results from this study suggest that much of the previous studies on the epidemiology of VVC should be re-thought. C. albicans was susceptible to most of the tested antifungals.

Molecular identification and antifungal susceptibility testing of Pucciniomycotina red yeast clinical isolates from Rio de Janeiro, Brazil

Infections caused by Rhodotorula spp. are increasing worldwide. This study identified, through the light of the new taxonomic advances on the subphylum Pucciniomycotina, 16 isolates from blood cultures and compared their antifungal susceptibility on microdilution and gradient diffusion methods. Internal transcriber spacer sequencing identified Rhodotorula mucilaginosa (n = 12), Rhodotorula toruloides (n = 2), Rhodotorula dairenensis (n = 1), and Cystobasidium minutum (n = 1). Amphotericin B was the most effective drug. A good essential agreement was observed on MIC values of amphotericin B and voriconazole determined by the two methods. Therefore, the gradient method is useful for susceptibility tests of R. mucilaginosa against these drugs.

Epidemiology and antifungal susceptibility patterns of Candida isolates from Greek women with vulvovaginal candidiasis

Vulvovaginal candidiasis (VVC) is a common infection of the genital tract affecting millions of women worldwide. Data on epidemiological trends of VVC in Greece are scarce. This study was undertaken to evaluate the prevalence of VVC among symptomatic women in Crete, Greece, identify the Candida species involved and determine their susceptibility to antifungals. Over a 6-year period (2012-2017), 10 256 symptomatic women with vaginitis were evaluated. Isolation of yeasts was performed on Sabouraud dextrose agar with chloramphenicol, and the isolates were identified using the API 20 C AUX and/or the Vitek 2 YST card. Susceptibility of the isolates to amphotericin, fluconazole, voriconazole and flucytosine was determined by the Vitek 2 automated system. The results were interpreted according to Clinical and Laboratory Standards criteria. Vaginal swab cultures of 1217 (11.9%) women yielded Candida species. Recurrent VVC was documented in 62 (5.1%) of them. Candida albicans was the most frequently isolated species (75.6%), followed by Candida glabrata (13.6%). Overall, resistance rates to amphotericin B, fluconazole, voriconazole and flucytosine were 0.2%, 6.6%, 1.4% and 2.1%, respectively. Fluconazole resistance of C. albicans significantly increased in the second period of the study (2015-2017) (P = 0.031). This study demonstrated that VVC is a common infection among women in our region, with C. albicans being the predominant species involved. Although resistance to antifungals was infrequent, resistance to fluconazole among C. albicans isolates was found to significantly increase with time. Continued surveillance of changes in species distribution and susceptibility to antifungals are necessary to guide treatment.

Vaginal candidiasis among women of reproductive age in Dnipro city (Ukraine): Species spectrum of Candida and their susceptibility to antimycotics

Candidiasis is one of the most common pathological processes, especially among women of reproductive age, especially pregnant. It can be expressed as Candida carriage and as an active form of infection. Although candidiasis is caused by opportunistic microorganisms, its effects can be quite significant, so it is necessary to treat it with the use of antimycotic drugs. In view of the spread among these microorganisms of resistance to antimicrobial drugs, the determining factor for the success of therapeutic measures, it is important to make a preliminary assessment of the susceptibility to antimycotics of strains isolated from persons with Candida carriage or active candidiasis. The aim of the research was to study the species range of fungi of the genus Candida isolated from the reproductive tract in women with dysbiosis and to study their susceptibility to antimycotics. Total of 227 samples of biological material from women aged 16 to 56 years have been investigated. Microscopic and cultural methods of detecting of fungi in the primary material were used for research. For the identification of species of Candida fungi, a polymerase chain reaction method in real-time was used. It was determined that the frequency of detection of Candida fungi in the composition of vaginal microbiome during inflammatory pathological processes was 76.7%. It was shown that the incidence of Candida carriage – 51.7% – slightly exceeded the frequency of detection of the active form of infection – 48.3%. The species spectrum of pathogens included: C. albicans (57.1%), C. krusei (12.6%), C. glabrata (19.5%) and Candida spp. (16.1%). In the case of active form of infection, C. albicans was prevalent – 64 (76.2%) cases. In the case of Candida carriage, other species were prevalent – 58 (64.4%) cases. The most effective drug against all isolates was amphotericin B – more than 87% of isolates were susceptible. The least effective drug was nystatin: less than 60% of isolates were susceptible. There is a rather high level of resistance to certain antimycotic drugs among the Candida species, which requires a prior preliminary study of the susceptibility of isolated strains to antimycotics for the purpose of choosing a rational and effective treatment scheme.

Antifungal Susceptibility Profile of Candida Albicans Isolated from Vulvovaginal Candidiasis in Xinjiang Province of China

We investigated the antifungal susceptibility profiles of 207 independent Candida albicans strains isolated from patients with vulvovaginal candidiasis (VVC) in Xinjiang Province of China. Using CLSI M27-A3 and M27-S4 guidelines, anidulafungin and micafungin were the most active drugs against C. albicans showing an MIC₅₀/MIC₉₀ corresponding to 0.016/0.0313 µg/mL, followed by caspofungin (0.25/0.25 µg/mL), posaconazole (0.125/0.5 µg/mL), ravuconazole (0.063/1 µg/mL), itraconazole (0.125/1 µg/mL), amphotericine B (0.5/1 µg/mL), isavuconazole (0.063/2 µg/mL), 5-flucytosine (1/2 µg/mL), voriconazole (0.125/4 µg/mL), and fluconazole (0.5/4 µg/mL). 96.1% (199)-100.0% (207) isolates were sensitive to the three echinocandins tested, amphotericine B and 5-flucytosine. The in vitro activity of triazoles against all isolates tested was variable; itraconazole and voriconazole had reduced the activity to almost half of the isolates (55.1% (114) and 51.2% (106) susceptible, respectively). Fluconazole was active against 76.3% (158) isolates tested. The new triazoles ravuconazole, isavuconazole and posaconazole showed good in vitro potency against 89.9% (186)-95.2% (197) of isolates with the geometric mean MIC (µg/mL) of 0.10, 0.12 and 0.14 µg/mL, respectively. In conclusion, our study indicates that for effective management of systemic candidiasis in Xinjiang Province of China, it is important to determine the susceptibility profiles of isolated C. albicans from patients with VVC.

Comparative Analysis of the Capacity of the Candida Species To Elicit Vaginal Immunopathology

The human fungal pathogen Candida albicans is the major etiological agent of vulvovaginal candidiasis (VVC). Despite this fact, other non-albicans Candida (NAC) species have frequently been reported, as well. Despite their presence in the vaginal environment, little is known about their capacities to elicit immune responses classically associated with C. albicans-mediated immunopathology, including neutrophil recruitment and proinflammatory cytokine signaling. Therefore, using a combination of in vitro and in vivo approaches, we undertook a comparative analysis to determine whether a representative panel of NAC species could colonize, induce immunopathological markers, or cause damage at the vaginal mucosa. Using a murine model of VVC, C. albicans was found to induce robust immunopathology (neutrophils and interleukin 1β [IL-1β]) and elicit mucosal damage. However, all the NAC species tested (including C. dubliniensis, C. tropicalis, C. parapsilosis, C. krusei, C. glabrata, and C. auris) induced significantly less damage and neutrophil recruitment than C. albicans, despite achieving similar early colonization levels. These results largely correlated with a notable lack of ability by the NAC species (including C. dubliniensis and C. tropicalis) to form hyphae both in vitro and in vivo Furthermore, both C. dubliniensis and C. tropicalis induced significantly less expression of the ECE1 gene encoding candidalysin, a key fungal virulence determinant driving VVC immunopathology. In order to determine the relative capacities of these species to elicit inflammasome-dependent IL-1β release, both wild-type and NLRP3^-/- THP-1 cells were challenged in vitro While most species tested elicited only modest amounts of IL-1β, challenge with C. albicans led to significantly elevated levels that were largely NLRP3 dependent. Collectively, our findings demonstrate that although NAC species are increasingly reported as causative agents of VVC, C. albicans appears to be exceedingly vaginopathogenic, exhibiting robust immunopathology, hypha formation, and candidalysin expression. Thus, this study provides mechanistic insight into why C. albicans is overwhelmingly the major pathogen reported during VVC.

An Update on the Roles of Non-albicans Candida Species in Vulvovaginitis

Candida species are one of the commonest causes of vaginitis in healthy women of reproductive age. Vulvovaginal candidiasis (VVC) is characterized by vulvovaginal itching, redness and discharge. Candida albicans, which is a common genito-urinary tract commensal, has been the prominent species and remains the most common fungal agent isolated from clinical samples of patients diagnosed with VVC. In recent times, however, there has been a notable shift in the etiology of candidiasis with non-albicans Candida (NAC) species gaining prominence. The NAC species now account for approximately 10% to as high as 45% of VVC cases in some studies. This is associated with treatment challenges and a slightly different clinical picture. NAC species vaginitis is milder in presentation, often occur in patients with underlying chronic medical conditions and symptoms tend to be more recurrent or chronic compared with C. albicans vaginitis. C. glabrata is the most common cause of NAC-VVC. C. tropicalis, C. krusei, C. parapsilosis, and C. guilliermondii are the other commonly implicated species. Treatment failure is common in NAC-VVC, since some of these species are intrinsically resistant or show low susceptibilities to commonly used antifungal agents. This article reviews the etiology, pathogenesis, clinical features, diagnosis, and management of NAC vulvovaginitis.

Candida parapsilosis Vaginal Infection-a New Site of Azole Drug Resistance

PURPOSE OF REVIEW

Evaluation of pathogenicity of an uncommon vaginal Candida species, Candida parapsilosis with particular references to susceptibility to conventional antifungal agents.

RECENT FINDINGS

C. parapsilosis vaginal isolates usually present in asymptomatic women as commensals but may induce vulvovaginal symptoms indistinguishable from C. albicans requiring antifungal therapy; however, recent experience reveals clinically relevant resistance to the azole class of antimycotics.

CONCLUSION

Clinicians are required to determine a causal relationship between vaginal isolates of C. parapsilosis before prescribing antifungal agents, recognizing the possibility of fluconazole resistance to explain refractory symptomatology.

Detection of Candida species in pregnant Chinese women with a molecular beacon method

Purpose

Candida pathogens are commonly found in women and can cause vulvovaginal candidiasis (VVC), whose infection rate is further increased during pregnancy. We aimed to study the Candida prevalence and strain distribution in pregnant Chinese women with a molecular beacon assay.

Methodology

From March 2016 to February 2017, a total of 993 pregnant women attending routine antenatal visits at the Beijing Obstetrics and Gynecology Hospital were enrolled. For Candida detection and identification, a unique molecular beacon assay was presented and compared with a traditional phenotypic method. Antifungal susceptibility was tested with the following agents: 5-flucytosine, amphotericin B, fluconazole, itraconazole and voriconazole.

Results

The prevalence of Candida was found to be 21.8 % when using the molecular method and 15.0 % when using the phenotypic method. The distribution of the Candida spp. was listed in order of decreasing prevalence: Candida albicans (79.8 %), Candida glabrata (13.5 %), Candida parapsilosis (3.7 %), Candida krusei (2.2 %) and Candida tropicalis (1.1 %). We found that 90.7 % of the Candida detection results were consistent between the molecular and the phenotypic methods. In the cases where the sequencing analyses for the Candida isolates resulted in inconsistent identification, the molecular method showed higher sensitivity than the phenotypic method (96.0 vs 64.6 %). C. albicans, C. glabrata and C. parapsilosis were essentially susceptible to all five antifungal agents tested, whereas C. tropicalis and C. krusei were susceptible to voriconazole and amphotericin B.

Conclusion

By exhibiting good sensitivity and specificity, the molecular assay may offer a fast and accurate Candida screening platform for pregnant women.

[Vulvovaginal candidiasis in pregnant women in the Mère et Enfant Hospital center in Nouakchott, Mauritania]

AIM

To determine the prevalence and the associated risk factors of vulvovaginal candidiasis in pregnant women in Mauritania.

PATIENTS AND METHOD

The study was carried out at the laboratory of the Mère et Enfant Center in Nouakchott, from November 1, 2016 to February 5, 2017. It concerned all pregnant women in the third trimester that came to the natal consultation at the gynecology service. These women must have given their informed consent in written form. After completing the survey to collect epidemiological and clinical data, a sample was collected to perform fresh direct examination and culture on Sabouraud-Chloramphenicol media.

RESULTS

Two hundred pregnant women were included in the study. Culture on Sabouraud-Chloramphenicol media was positive in 52 patients corresponding to a prevalence of 26%. The germ tube test was positive for 61.5% of isolated Candida. Clinical signs are dominated by leucorrhea (56%), pelvic pain (25%) and vulvar pruritus (11%). Among women with positive culture, 55.76% had received local antifungal treatment in the form of an ovula during pregnancy.

CONCLUSION

This study shows that vulvovaginal candidiasis is frequent in pregnant women attending gynecology at the Mère et Enfant Hospital Center in Nouakchott.

Prevalence of vulvovaginal candidiasis in pregnancy at three health centers in Burkina Faso

INTRODUCTION

Pregnant women are more susceptible to vaginal colonization and infection by yeast. The role of Candida colonization in the occurrence of preterm birth is well established. The knowledge of local epidemiology and identification of risk factors for preterm birth is important for the prevention and management strategies. The purpose of the study was to determine the prevalence of Candida sp. in vaginal swabs of pregnant women.

METHODS

Pregnant women attending routine antenatal visits in three primary health centres in Bobo-Dioulasso (Burkina Faso) were enrolled into a cross-sectional study carried out from February to April 2015. Vaginal swabs samples were taken from participants after obtaining oral consent. The swabs were inoculated into Sabouraud's glucose agar supplemented with chloramphenicol and incubated at 37°C for 24 to 48hours under aerobic conditions in order to perform fungal culture. The identification of the Candida species was done by culture on HiCrome Candida Differential Agar at 35°C for 48h for production of species-specific colors.

RESULTS

A total of 229 pregnant women were included. The prevalence of vulvovaginal candidiasis (VVC) was 22.71%, (95% CI [17.45-28.69]). Candida albicans accounted for 40.39% and non-Candida albicans species for 59.61% of the isolates, with mainly C. glabrata (32.69%), C. tropicalis (15.38%) and C. krusei (11.54%).

CONCLUSIONS

This study revealed a high prevalence of non-C. albicans species. The syndromic management guidelines for VVC in Burkina Faso will be revised to include a specific protocol for pregnant women.

Prevalence of Candida albicans, Candida dubliniensis and Candida africana in pregnant women suffering from vulvovaginal candidiasis in Argentina

BACKGROUND

Vulvovaginal candidiasis (VVC) is a vulvovaginitis commonly diagnosed in gynecology care. In recent years, the taxonomy of the most important pathogenic Candida species, such as Candida albicans have undergone significant changes.

AIMS

This study examined the prevalence of C. albicans, Candida africana, and Candida dubliniensis in vaginal specimens from 210 pregnant women suffering from vulvovaginitis or having asymptomatic colonization.

METHODS

Phenotypic and molecular methods were used for the identification of the species.

RESULTS

During the studied period, 55 isolates of Candida or other yeasts were obtained from specimens collected from 52 patients suffering from vulvovaginitis (24.8%). C. albicans was the predominant Candida species in 42 isolates (80.7%), either alone or in combination with other species of the genus (5.7%, n=3). Additionally, nine isolates of C. albicans (50%) were obtained from asymptomatic patients (n=18). C. dubliniensis was the causative agent in 2 (3.8%) cases of VVC, and was also isolated in one asymptomatic patient. Molecular assays were carried out using specific PCR to amplify the ACT1-associated intron sequence of C. dubliniensis. The amplification of the HWP1 gene also correctly identified isolates of the species C. albicans and C. dubliniensis. No C. africana was isolated in this work. Some C. albicans isolates were either homozygous or heterozygous at the HWP1 locus. The distribution of heterozygous and homozygous C. albicans isolates at the HWP1 locus was very similar among patients suffering from VVC and asymptomatic patients (p=0.897).

CONCLUSIONS

The presence of C. albicans and C. dubliniensis, and the absence of C. africana in pregnant is noteworthy.

Vulvovaginal candidiasis: Etiology, symptomatology and risk factors

OBJECTIVE

To determine epidemiological, clinical and mycological characteristics of vulvovaginal candidiasis (VVC) in Tunisian population and to evaluate predisposing factors.

PATIENTS AND METHODS

In this retrospective study, 2160 vaginal swabs were performed over 2 years (January 2014-December 2015). It was carried out at the laboratory of Parasitology and Mycology, Rabta Hospital in Tunisia. After swab collecting, direct examination and culture on Sabouraud Chloramphenicol and Sabouraud Chloramphenicol Actidione media were implemented to research yeasts. Then identifying of yeast species was through chlamydosporulation test and auxanogram. For each patient, a questionnaire was filled noting age, medical and surgical history, symptoms and risk factors. Statistical analysis of data was performed on SPSS 16 using Khi² test, P<0.05 was considered significant.

RESULTS

Direct examination was positive showed spore and/or pseudohypha in 24.72%. Candida albicans was isolated most frequently (76.61%) followed by Candida glabrata (17.18%). The maximum frequency of Candida-positive cultures was in 25-34 years old age group. Leucorrhea was the most common symptom (72.25%) followed by vulvar prurits (63.23%), dyspareunia (32.25%) and urinary burning (24.92%). Only pregnancy was correlated positively with VVC.

CONCLUSION

It appears from our study that VVC is relatively common in Tunisia. His diagnosis results from confrontation of anamnestic, clinical and mycological data. The knowledge of risk factors and their correction would be necessary to prevent the occurrence of VVC, especially in its recurrent form.

Scientific Opinion on the update of the list of QPS-recommended biological agents intentionally added to food or feed as notified to EFSA

EFSA is requested to assess the safety of a broad range of biological agents in the context of notification for market authorisation as sources of food and feed additives, food enzymes and plant protection products. The qualified presumption of safety (QPS) assessment was developed to provide a harmonised generic pre-assessment to support safety risk assessments performed by EFSA's scientific Panels. The safety of unambiguously defined biological agents (at the highest taxonomic unit appropriate for the purpose for which an application is intended), and the completeness of the body of knowledge are assessed. Identified safety concerns for a taxonomic unit are, where possible and reasonable in number, reflected as 'qualifications' in connection with a recommendation for a QPS status. The list of QPS recommended biological agents was reviewed and updated in the current opinion and therefore becomes the valid list. The 2016 update reviews previously assessed microorganisms including bacteria, yeasts and viruses used for plant protection purposes following an Extensive Literature Search strategy. The taxonomic units related to the new notifications received since the 2013 QPS opinion, were periodically evaluated for a QPS status and the results published as Statements of the BIOHAZ Panel. Carnobacterium divergens, Lactobacillus diolivorans, Microbacterium imperiale, Pasteuria nishizawae, Pediococcus parvulus, Bacillus flexus, Bacillus smithii, Xanthomonas campestris and Candida cylindracea were recommended for the QPS list. All taxonomic units previously recommended for the 2013 QPS list had their status reconfirmed as well their qualifications with the exception of Pasteuria nishizawae for which the qualification was removed. The exclusion of filamentous fungi and enterococci from the QPS evaluations was reconsidered but monitoring will be maintained and the status will be re-evaluated in the next QPS Opinion update. Evaluation of bacteriophages should remain as a case-by-case procedure and should not be considered for QPS status.

Species Distribution and In Vitro Antifungal Susceptibility of Vulvovaginal Candida Isolates in China

BACKGROUND

Vulvovaginal candidiasis (VVC) was a common infection associated with lifelong harassment of woman's social and sexual life. The purpose of this study was to describe the species distribution and in vitroCandidaCandida spp.) isolated from patients with VVC over 8 years.

METHODS

Species which isolated from patients with VVC in Peking University First Hospital were identified using chromogenic culture media. Susceptibility to common antifungal agents was determined using agar diffusion method based on CLSI M44-A2 document. SPSS software (version 14.0, Inc., Chicago, IL, USA) was used for statistical analysis, involving statistical description and Chi-square test.

RESULTS

The most common strains were Candida (C.) albicans, 80.5% (n = 1775) followed by C. glabrata, 18.1% (n = 400). Nystatin exhibited excellent activity against all species (<4% resistant [R]). Resistance to azole drugs varied among different species. C. albicans: clotrimazole (3.1% R) < fluconazole (16.6% R) < itraconazole (51.5% R) < miconazole (54.0% R); C. glabrata: miconazole (25.6% R) < clotrimazole (50.5% R) < itraconazole (61.9% R) < fluconazole (73.3% R); Candida krusei: clotrimazole (0 R) < fluconazole (57.7% R) < miconazole (73.1% R) < itraconazole (83.3% R). The susceptibility of fluconazole was noticeably decreasing among all species in the study period.

CONCLUSIONS

Nystatin was the optimal choice for the treatment of VVC at present. The species distribution and in vitroCandida spp. isolated from patients with VVC had changed over time.

Distribution and Drug Susceptibility of Candida spp. Associated With Female Genital Tract Infection, Chongqing, China

BACKGROUND

Vulvovaginal candidiasis is defined as vulvovaginitis associated with vaginal carriage of Candida spp. and is a common problem with a high rate of morbidity.

OBJECTIVES

To investigate the distribution of Candida spp. and evaluate the corresponding antifungal susceptibility in women with genital tract infection in Chongqing, southwestern China.

PATIENTS AND METHODS

Samples (n = 2.129) were obtained from female patients with symptoms of genital tract infection. Candida spp. were isolated from the specimens and were identified using a coloration medium and the VITEK 2 Compact automatic microbial identification system. Antifungal susceptibility testing was performed using the ATB FUNGUS drug susceptibility testing system.

RESULTS

From 2,129 samples, 478 (22.45%) isolates of Candida were isolated, of which 395 (82.64%) were Candida albicans, 39 (8.16%) were C. glabrata, 21 (4.39%) were C. tropicalis, 9 (1.88%) were C. parapsilosis, and 14 (2.93%) were other Candida spp. The resistance of C. albicans, C. glabrata, and C. tropicalis to 5 antifungal drugs (amphotericin B, voriconazole, fluconazole, 5-fluorocytosine, and itraconazole) ranged from 0.5% to 6.4%, 0% to 7.7%, and 0% to 9.6%, respectively.

CONCLUSIONS

Candida albicans was the major pathogen associated with candidiasis of the female genital tract in patients in Chongqing. The results of the antifungal sensitivity of the isolates suggest that it is important for clinicians to administer appropriate antifungals for the treatment of Candida spp. infections.

A randomized clinical trial of the efficacy and safety of terconazole vaginal suppository versus oral fluconazole for treating severe vulvovaginal candidiasis

Terconazole is a new, broad-spectrum, triazole antifungal agent. The aim of this study was to compare the efficacy and safety of a 6-day course of a terconazole vaginal suppository (80 mg) with two doses of oral fluconazole (150 mg) for the treatment of severe vulvovaginal candidiasis (SVVC). In this prospective, randomized case-control study, 140 consecutive patients with SVVC were enrolled at the Department of Obstetrics and Gynecology of Peking University Shenzhen Hospital from July 1, 2013, through June 31, 2014. Patients with SVVC, initially at a 1:1 ratio, were randomly assigned to receive treatment with either the terconazole vaginal suppository or oral fluconazole. The patients had follow-up visits at 7-14 days and 30-35 days following the last dose of therapy. The clinical cure rates in the terconazole group and the fluconazole group were, respectively, 81.0% (47/58) and 75.8% (50/66) at follow-up day 7-14 and 60.3% (35/58) and 56.1% (37/66) at day 30-35. The mycological cure rates in the two groups were, respectively, 79.3% (46/58) and 71.2% (47/66) at follow-up day 7-14 and 62.1% (36/58) and 53.0% (35/66) at day 30-35 (P > .05 for all). Local irritation was the primary adverse event associated with terconazole, whereas systemic side effects were associated with fluconazole; however, these effects were minimal. This study demonstrated that a terconazole vaginal suppository (80 mg daily for 6 days) was as effective as two dose of oral fluconazole (150 mg) in the treatment of patients with SVVC; as such, terconazole could be a choice for therapy of this disorder.

The Role of PCR in the Diagnosis of Candida Vulvovaginitis-a New Gold Standard?

PCR is recognized as a reliable technique for detection of all types of microorganisms. Being highly objective and reproducible also sensitive and specific, PCR is now widely used for sexually transmitted infection (STI) diagnosis. Potential, however, exists for detecting non-pathogens, and not identifying a pathogenic state decreases specificity or clinical significance. PCR Candida tests of vaginal specimens are now widely available and frequently used offering a modest to moderate increase in sensitivity and are likely to replace traditional culture and DNA homology testing. Nevertheless, there remain considerable gaps in our knowledge regarding the usefulness and applications of these expensive tests.

Cellular Structural Changes in Candida albicans Caused by the Hydroalcoholic Extract from Sapindus saponaria L

Vulvovaginal candidiasis (VVC) is a disease caused by the abnormal growth of yeast-like fungi in the mucosa of the female genital tract. Candida albicans is the principal etiological agent involved in VVC, but reports have shown an increase in the prevalence of Candida non-C. albicans (CNCA) cases, which complicates VVC treatment because CNCA does not respond well to antifungal therapy. Our group has reported the in vitro antifungal activity of extracts from Sapindus saponaria L. The present study used scanning electron microscopy and transmission electron microscopy to further evaluate the antifungal activity of hydroalcoholic extract from S. saponaria (HE) against yeast obtained from VVC and structural changes induced by HE. We observed the antifungal activity of HE against 125 vaginal yeasts that belonged to four different species of the Candida genus and S. cerevisae. The results suggest that saponins that are present in HE act on the cell wall or membrane of yeast at the first moments after contact, causing damage to these structures and cell lysis.

Propolis Is an Efficient Fungicide and Inhibitor of Biofilm Production by Vaginal Candida albicans

Vulvovaginal candidiasis (VVC) is one of the most common genital infections in women. The therapeutic arsenal remains restricted, and some alternatives to VVC treatment are being studied. The present study evaluated the influence of a propolis extractive solution (PES) on biofilm production by Candida albicans isolated from patients with VVC. Susceptibility testing was used to verify the minimum inhibitory concentration (MIC) of PES, with fluconazole and nystatin as controls. The biofilm formation of 29 vaginal isolates of C. albicans and a reference strain that were exposed to PES was evaluated using crystal violet staining. Colony-forming units were evaluated, proteins and carbohydrates of the matrix biofilm were quantified, and scanning electron microscopy was performed. The MIC of PES ranged from 68.35 to 546.87 μg/mL of total phenol content in gallic acid. A concentration of 546.87 μg/mL was able to cause the death of 75.8% of the isolates. PES inhibited biofilm formation by C. albicans from VVC. Besides antifungal activity, PES appears to present important antibiofilm activity on abiotic surfaces, indicating that it may have an additional beneficial effect in the treatment of VVC.

Molecular identification and antifungal susceptibility of 186 Candida isolates from vulvovaginal candidiasis in southern China

There is limited information regarding the molecular epidemiology and antifungal susceptibilities of Candida isolates using the Neo-Sensitabs method in patients with vulvovaginal candidiasis (VVC). From August 2012 to March 2013, 301 non-pregnant patients aged 18-50 years with suspected VVC were prospectively screened at a teaching hospital in southern China. The vaginal isolates were identified by DNA sequencing of internal transcribed spacer and the D1/D2 domain. Antifungal susceptibility testing of seven antifungal agents was performed using the Neo-Sensitabs tablet diffusion method. Candida species were isolated from 186 cases (61.79 %). The most common pathogen was Candida albicans (91.4 %), followed by Candida glabrata (4.3 %), Candida tropicalis (3.2 %) and Candida parapsilosis (1.1 %). The susceptibility rates to C. albicans were higher for caspofungin, voriconazole and fluconazole than those for itraconazole, miconazole, ketoconazole and terbinafine (P<0.01). The resistance rates to C. albicans were 4.7, 6.5, 7.1, 7.6, 12.3, 27.7 and 74.7 % for caspofungin, miconazole, itraconazole, voriconazole, fluconazole, ketoconazole and terbinafine, respectively. No drugs tested apart from fluconazole exhibited differences in resistance between C. albicans and non-albicans Candida isolates. The results demonstrate that, using DNA sequencing, C. albicans is the most common isolate from Chinese patients with VVC. Caspofungin, voriconazole and fluconazole may be preferable to other azoles and terbinafine in the treatment of VVC.

Prevalence of Candida nivariensis and Candida bracarensis in vulvovaginal Candidiasis

Candida nivariensis and Candida bracarensis were isolated from patients with vulvovaginal candidiasis (VVC). Candida nivariensis and Candida bracarensis were found in presumptive Candida glabrata isolates, which were identified using the API Candida system. We retrospectively re-examined vaginal presumptive Candida glabrata isolates for Candida nivariensis and Candida bracarensis from January 1, 2003, through December 31, 2012, via detection of the ITS1 region and the 5.8S ribosomal RNA gene. Among 301 presumptive Candida glabrata isolates, 293 isolates were confirmed as C. glabrata (97.34 %), 7 isolates were identified as C. nivariensis (2.33 %) and 1 isolate was identified as C. bracarensis (0.33 %). The C. nivariensis and C. bracarensis isolates were confirmed by sequencing. All C. nivariensis isolates were susceptible to nystatin and susceptible or susceptible dose-dependent to fluconazole, itraconazole, miconazole, and clotrimazole. The C. bracarensis isolate was susceptible to nystatin and the tested azoles. Among the seven patients with VVC caused by C. nivariensis and who were treated with various antifungal agents, only one patient achieved mycological eradication at both the day 7-14 and day 30-35 follow-ups. The C. bracarensis isolate was isolated from a symptomatic pregnant woman; additional data for this patient were unavailable. We conclude that C. nivariensis and C. bracarensis existed in the vaginal samples of patients with VVC. Therapeutic efficacy in the patients with C. nivariensis was poor and inconsistent with the observed in vitro antifungal susceptibility, which requires further study.