Epidemiology and antifungal susceptibilities of yeasts causing vulvovaginitis in a teaching hospital

Rare Yeasts in Latin America: Uncommon Yet Meaningful

Systemic infections caused by rare yeasts are increasing given the rise in immunocompromised or seriously ill patients. Even though globally, the clinical significance of these emerging opportunistic yeasts is increasingly being recognized, less is known about the epidemiology of rare yeasts in Latin America. This review collects, analyzes, and contributes demographic and clinical data from 495 cases of infection caused by rare yeasts in the region. Among all cases, 32 species of rare yeasts, distributed in 12 genera, have been reported in 8 Latin American countries, with Trichosporon asahii (49.5%), Rhodotorula mucilaginosa (11.1%), and Saccharomyces cerevisiae (7.8%) the most common species found. Patients were mostly male (58.3%), from neonates to 84 years of age. Statistically, surgery and antibiotic use were associated with higher rates of Trichosporon infections, while central venous catheter, leukemia, and cancer were associated with higher rates of Rhodotorula infections. From all cases, fungemia was the predominant diagnosis (50.3%). Patients were mostly treated with amphotericin B (58.7%). Crude mortality was 40.8%, with a higher risk of death from fungemia and T. asahii infections. Culture was the main diagnostic methodology. Antifungal resistance to one or more drugs was reported in various species of rare yeasts.

The impact of antimicrobial management by clinical pharmacists in obstetrics and gynecology on antimicrobial indicators, bacterial resistance and drug costs from 2011 to 2021 in China

Objectives

The goal of our study is to analyze the effectiveness and role of clinical pharmacists in antibiotic management through retrospective research from 2011 to 2021, depending on the current scenario of the antibiotic application in China.

Methods

We formed a team of pharmacists to carry out multifaceted intervention measures, such as forming a working group, developing a plan, establishing management rules via the pre-trial system, prescription comments, collaborating with the administrative department, implementing training and publicity, and so on. Antibiotic use was studied, bacterial drug resistance was determined, and antibiotic costs were computed.

Results

The pharmacist intervention and rectification of inappropriate antibacterial drug orders considerably enhanced the rational use rate of antibiotics and reduced the cost of antibiotics. Antibiotic use in clean surgery decreased from 90.22% to 11.14%, the use rate of antibiotics decreased from 63.82% to 30.26%, and antibiotic use intensity decreased from 42.75DDDs to 30.04DDDs. The types, timing, and course of antibacterials used in wards were all improved to varying degrees. Bacterial drug resistance improved noticeably, with resistance of Escherichia coli to cephalosporins, ciprofloxacin and carbapenems decreased in varying degrees. The use of antibacterial drugs has decreased significantly.

Conclusions

It is feasible and effective for pharmacists in gynecology and obstetrics to control antibiotic use, which plays a positive role in promoting the safe, effective, and cost-effective use of antibiotics and serves as a valuable reference for the antibiotic management.

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.

Antifungal activity of linalool against fluconazole-resistant clinical strains of vulvovaginal Candida albicans and its predictive mechanism of action

Candida albicans is the most frequently isolated opportunistic pathogen in the female genital tract, with 92.3% of cases in Brazil associated with vulvovaginal candidiasis (VVC). Linalool is a monoterpene compound from plants of the genera Cinnamomum, Coriandrum, Lavandula, and Citrus that has demonstrated a fungicidal effect on strains of Candida spp., but its mechanism of action is still unknown. For this purpose, broth microdilution techniques were applied, as well as molecular docking in a predictive manner for this mechanism. The main results of this study indicated that the C. albicans strains analyzed were resistant to fluconazole and sensitive to linalool at a dose of 256 µg/mL. Furthermore, the increase in the minimum inhibitory concentration (MIC) of linalool in the presence of sorbitol and ergosterol indicated that this molecule possibly affects the cell wall and plasma membrane integrity of C. albicans. Molecular docking of linalool with proteins that are key in the biosynthesis and maintenance of the cell wall and the fungal plasma membrane integrity demonstrated the possibility of linalool interacting with three important enzymes: 1,3-β-glucan synthase, lanosterol 14α-demethylase, and Δ 14-sterol reductase. In silico analysis showed that this monoterpene has theoretical but significant oral bioavailability, low toxic potential, and high similarity to pharmaceuticals. Therefore, the findings of this study indicated that linalool probably causes damage to the cell wall and plasma membrane of C. albicans, possibly by interaction with important enzymes involved in the biosynthesis of these fungal structures, in addition to presenting low in silico toxic potential.

Vulvovaginal candidiasis and asymptomatic vaginal colonization in Portugal: epidemiology, risk factors and antifungal pattern

Vulvovaginal candidiasis (VVC) has been identified as a global issue of concern due to its clinical, social and economic implications. The emerging relevance of VVC makes it crucial to increase the knowledge on its epidemiological and etiological features in order to improve its prevention and treatment. Thus, this study aimed to reveal the incidence, microbiology, antifungal pattern and risk factors of VVC in Portugal. For that, high vaginal samples were collected from 470 symptomatic and asymptomatic participants; Candida spp. were identified with molecular techniques and their antifungal susceptibility was analysed with E-tests. The results revealed an incidence of VVC among women with vulvovaginitis of 74.4%. Furthermore, 63.7% of asymptomatic women were colonized with Candida spp. Importantly, women with history of recurrent vaginal infections, those who use over-the-counter antifungals, oral contraceptive pills and non-cotton underwear were found to be at significantly higher risk of developing VVC. Candida albicans was the most common species (59%), followed by Candida glabrata (27%), in a total of 8 distinct species, with similar distribution among colonized and infected participants. Of note, various isolates, especially of the most common species, showed low susceptibility towards fluconazole. In contrast, only few isolates showed low susceptibility towards caspofungin. Overall, this study suggests that the identification of species causing VVC and their antifungal susceptibility are urgently needed in clinical practice in order to improve the decision for the most adequate treatment. It also suggests that avoiding certain risk behaviours may prevent the development of VVC.

Vulvovaginal Candidiasis: A Review of the Evidence for the 2021 Centers for Disease Control and Prevention of Sexually Transmitted Infections Treatment Guidelines

BACKGROUND

Vulvovaginal candidiasis (VVC) is a common cause of vulvovaginal itching and discharge. This article discusses the latest CDC STI Treatment Guidelines for VVC.

METHODS

A literature search of relevant topics was performed, and a team of experts was convened to discuss (1) diagnosis/testing modalities; treatment of (2) uncomplicated VVC , (3) complicated VVC, and (4) VVC caused by non-albicans yeast; (5) alternative treatment regimens; (6) susceptibility testing of yeast; Special Populations: (7) pregnancy and (8) HIV and VVC.

RESULTS

Yeast culture remains the gold standard for diagnoses. Newer molecular assays have been developed for the diagnosis of VVC and perform well. Azole antifungals remain the treatment of choice for uncomplicated VVC. Two new drugs, TOL-463 and recently FDA-approved ibrexafungerp, appeared promising in clinical trials. For recurrent VVC, oteseconazole, not yet commercially available, may represent a new option. For non-albicans yeast infections in symptomatic patients, boric acid appears useful. No evidence supports the use of alternative treatments, including probiotics. Fluconazole during pregnancy may be associated with spontaneous abortion and craniofacial and heart defects. In women with HIV infection, lower CD4+ T-cell counts are associated with increased rates of VVC, and VVC is associated with increased viral shedding. Treatment measures in women with HIV infection are identical to those women without HIV infection.

CONCLUSIONS

There has been significant new knowledge generated about VVC since the 2015 CDC Guidelines which have led to changing recommendations.

A prospective study on vulvovaginal candidiasis: multicentre molecular epidemiology of pathogenic yeasts in China

BACKGROUND

Vulvovaginal candidiasis (VVC) is frequent in women of reproductive age, but very limited data are available on the epidemiology in cases of VVC in China.

OBJECTIVES

The current study has been conducted to reveal the prevalence, species distribution of yeast causing VVC and molecular genetics of Candida albicans in China.

METHODS

Vaginal swabs were collected from 543 VVC outpatients recruited in 12 hospitals in China between September 2017 and March 2018. They were preliminarily incubated on Sabouraud dextrose agar and then positive subjects of which were then transmitted to our institute for further identification. CHROMagar™ was used to isolate Candida species, and all isolates were finally identified by DNA sequencing. Multilocus sequence typing (MLST) was used to analyse phylogenetic relationships of the various C. albicans isolates.

RESULTS

Eleven different yeast species were identified in 543 isolates, among which C. albicans (84.7%) was the most frequent, followed by C. glabrata (8.7%). We obtained 117 unique diploid sequence types from 451 clinical C. albicans isolates and 92 isolates (20.4%) belonged to a New Clade. All the strains appearing in the New Clade were from northern China and they were isolated from non-recurrent VVC.

CONCLUSIONS

Our findings suggest that C. albicans are still the main cause of VVC in China and the majority of C. albicans isolates belongs to Clade 1 with DST 79 and DST 45 being two most common. Moreover, the New Clade revealed in our study seems to be specific to northern China.

Distribution of genetically characterized yeasts and its antifungals susceptibility in the hospital environment

Candida spp. is one of the main pathogens associated with nosocomial infection in Brazil and worldwide. The aim of this study was to evaluate the distribution of Candida yeasts in the ICU and their susceptibility to the antifungal agents terbinafine and fluconazole. The samples were collected by swabbing nine surfaces in the ICU of a hospital located in Pelotas, RS. These isolates were genetically characterized by sequencing the internal transcript spacer (ITS) using the primers ITS1 and ITS4. The test against antifungals was performed by Microdilution in Broth (CLSI-M27-A4). 64 yeasts identified as Candida parapsilosis (45.31%; n = 29), Meyerozyma (Pichia) guilliermondii (28.12%; n = 18), Claviceps lusitaneae (25%; n = 16) and Candida tropicalis (1, 56%; n = 1) mostly at the counter used for handling medicines and food distribution (68.75%; n = 44). Susceptibility to antifungals varied between species. These results describe potentially pathogenic Candida species as contaminants in the ICU environment. The study environment is a potential source of exogenous infection for hospitalized patients.

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.

Vaginal candidiasis in Konya area: Etiology, risk factors, virulence patterns, and antifungal susceptibility

Vulvovaginal candidiasis (VVC), a common genital tract infection, is known to affect millions of women worldwide. In this study, it was aimed to determine the prevalence, virulence, possible risk factors and antifungal susceptibility model of Candida species. Vaginal swab samples were taken from patients aged 18 years and older who presented to the gynecology outpatient clinic with signs and symptoms suggestive of vulvovaginitis. Demographic data were recorded using a questionnaire. Standard microbiological methods were used for the identification of the isolates. Broth microdilution method was used to determine the antifungal susceptibility of Candida isolates. Virulence factors of Candida strains were determined by performing proteinase, phospholipase, hemolytic and biofilm activity tests. Sequencing of the isolates identified as Candida were performed using ITS 1-4 primers. Vaginal discharge (OR: 3.365; 95% CI: 1.595-7.101), burning complaint (OR: 9.098; 95% CI: 2.284-36.232) and history of allergy (OR: 3.396; 95% CI: 0.968) were risk factors. The results showed that the most common isolated strain was Candida albicans (57%). It was found that the prevalence of C. glabrata remained at 26%, 44 of the C. albicans isolates presented proteinase, 35 had phospholipase, 47 had biofilm, and 47 had hemolytic activity. In this study, susceptible dose-dependent and resistant rates of all Candida strains were found for fluconazole as 9% and 16%, respectively. Host and organism-related factors should be considered in the clinical treatment of VVC, and continuous monitoring of changes in the prevalence of Candida species and susceptibility rates is required for effective antifungal therapy.

In Vitro activity of ravuconazole against Candida auris and vaginal candida isolates

BACKGROUND

Ravuconazole is an extended-spectrum triazole agent that is efficient in vitro against Candida spp. and has been approved to work as an oral formulae for onychomycosis in Japan in 2018. However, nobody had determined the MIC of ravuconazole against the Candida auris, which is known as an emerging multidrug-resistant yeast. Meanwhile, rare is known of the in vitro activity of ravuconazole against vaginal Candida isolates.

OBJECTIVES

To investigate the activity of ravuconazole against C. auris and vaginal Candida isolates of China and assess the feasibility of ravuconazole in the treatment of candidiasis caused by C. auris and other Candida spp.

METHODS

We determined the in vitro activity of ravuconazole and 9 comparators against 15 C. auris isolates and determined the MIC of ravuconazole on 525 vaginal Candida isolates (Candida albicans, Candida tropicalis, Candida glabrata and Candida parapsilosis) from 9 provinces of China by Clinical and Laboratory Standards Institute (CLSI) methodology.

RESULTS

The MICs of fluconazole and amphotericin B on C. auris were much higher than second-generation azoles and echinocandins. Ravuconazole was active against all the C. auris isolates and as effective as isavuconazole, posaconazole and echinocandins while showed a better antifungal activity than itraconazole, voriconazole to C. auris. For vaginal Candida isolates, the proportion of ravuconazole-resistant isolates is 0.19% (1/525).

CONCLUSIONS

Ravuconazole was in good active against C. auris and vaginal Candida isolates, which suggested ravuconazole could be used in the treatment of drug-resistant candidiasis.

Molecular Characterization and Antifungal Susceptibility of Candida Species Isolated From Vulvovaginitis in Jahrom City, South of Iran

Background: Vulvovaginal candidiasis (VVC) is a significant health issue due to Candida spp. Although Candida albicans is considered a major causative agent of vaginal candidiasis, non-albicans species have increased during previous decades. Objectives: This research aimed at molecular identification and assessing antifungal susceptibility of VVC isolated Candida spp. Methods: A professional physician examined two hundred and ninety-five suspected females with vaginitis. The specimens were collected by sterile cotton swabs. Swabs were inoculated on Sabouraud dextrose agar plates and then incubated for 48 - 72 hours at 35°C. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to detect all Candida species. Broth microdilution, according to the M27-A3 and M27-S4 CLSI documents, were employed for determining the antifungal susceptibility tests of caspofungin (CAS), voriconazole (VRC), itraconazole (ITC), fluconazole (FLU), clotrimazole (CLO), ketoconazole (KTO), amphotericin B (AMB), and nystatin (NYS). Results: A total of 295 females suspected of vulvovaginal candidiasis were examined. The culture results were positive in 50.5% (149 of 295) of specimens. According to molecular identification techniques, C. albicans 133/149 (89.2%), C. glabrata 8/149 (5.4%), and C. kefyr 2/149 (1.4%) were the main species. A mixed infection of C. albicans and C. glabrata 6/149 (4 %) was detected. The geometric mean values to all Candida strains were in increasing order as the following: CAS, 0.075 µg/mL; VRC, 0.091 µg/mL; ITC, 0.15 µg/mL; AMB, 0.22 µg/mL; CLO, 0.23 µg/mL; KTO, 0.28 µg/mL; NYS, 0.88 µg/mL; FLU, 1.48 µg/mL. Further, the MIC ranges of all Candida isolates to the tested antifungal agents were in increasing order as follows: CAS: 0.031 - 0.25 µg/mL, KTO and ITC: 0.031 - 2 µg/mL, VRC: 0.031 - 4 µg/mL, CLO and AMB: 0.031 - 8 µg/mL, NYS: 0.06 - 4 µg/mL, and FLU: 0.12 - 128 µg/mL. Conclusions: We reported 1 (7.2 %) C. glabrata isolate resistance to FLU and 2 (14.3%) C. glabrata isolates susceptible-dose-dependent (SDD) to CAS. We also reported 6 (4.5%), 5 (3.8%), and 2 (1.5%) C. albicans resistance to ITC, FLU, and AMB, respectively, but 100% C. albicans susceptible to CAS and VRC.

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.

RAFT-Derived Polymethacrylates as a Superior Treatment for Recurrent Vulvovaginal Candidiasis by Targeting Biotic Biofilms and Persister Cells

Background

Vulvovaginal candidiasis (VVC) is a common infection in need of more effective treatment. Formation of epithelium-associated Candida biofilms and the presence of persister cells are among the major contributing factors to the recurrence of this condition. We have previously developed RAFT-derived polymethacrylates that are effective in killing C. albicans biofilms in vitro. This study aimed to examine the clinical potential of polymethacrylates as antifungals for treatment of recurrent VVC (RVVC).

Methods

A mouse model of VVC was used to establish vaginal epithelium-associated biofilms, using C. albicans isolates from VVC/RVVC patients. A comparison was made of the efficacies of polymethacrylates and conventional antifungals, clotrimazole and nystatin, in killing Candida in epithelium-associated biofilms in vivo. Ex vivo biofilms were used for Candida population profiling and to quantify persister cells in vaginal epithelia. The potency of polymethacrylates and conventional antifungals against persister cells, either as sole agents or in combination, was assessed.

Results

Polymethacrylates showed negligible local toxicity, resistance to vaginal acidity, and outstanding in vivo activity against vaginal epithelium-associated C. albicans biofilms. In vivo tests polymethacrylates outperformed the conventional antifungals, nystatin and clotrimazole at concentrations 50 times below the over-the-counter concentrations. Using polymethacrylates was associated with fewer persister cells, and better eradication of persister cells pre-selected by conventional antifungals.

Conclusion

This study systematically assessed the clinical potential of RAFT-derived polymethacrylates as an effective treatment for VVC/RVVC in a mouse model. Polymethacrylates effectively killed vaginal epithelium-related C. albicans in vivo by specially targeting biotic biofilms and persister cells. Treatment presented negligible local toxicity.

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.

Antifungal activity of analogues of antimicrobial peptides isolated from bee venoms against vulvovaginal Candida spp

Candida albicans is the main causative agent of vulvovaginal candidiasis (VVC), a common mycosis in women, relapses of which are difficult to manage due to biofilm formation. This study aimed at developing novel non-toxic compounds active against Candida spp. biofilms. We synthesised analogues of natural antifungal peptides LL-III (LL-III/43) and HAL-2 (peptide VIII) originally isolated from bee venoms and elucidated their structures by nuclear magnetic resonance spectroscopy. The haemolytic, cytotoxic, antifungal and anti-biofilm activities of LL-III/43 and peptide VIII were then tested. LL-III/43 and VIII showed moderate cytotoxicity to HUVEC-2 cells and had comparable inhibitory activity against C. albicans and non-albicans spp. The lowest minimum inhibitory concentration (MIC90) of LL-III/43 was observed towards Candida tropicalis (0.8 µM). That was 8-fold lower than that of antimycotic amphotericin B. Both peptides can be used to inhibit Candida spp. bio film f ormation. Biofilm inhibitory concentrations (BIC50) ranged from 0.9 to 58.6 µM and biofilm eradication concentrations (BEC50) for almost all tested Candida spp. strains ranged from 12.8 to 200 µM. Als o pro ven were the peptides’ abilities to reduce the area colonised by biofilms , inhibit hyphae formation and permeabilise cell membranes in biofil ms . LL-III/43 and VIII are promising candidates for further development as therapeutics against VVC.

Prevalence of Candida africana and Candida dubliniensis, in vulvovaginal candidiasis: First Turkish Candida africana isolates from vulvovaginal candidiasis

INTRODUCTION

Candida africana and C. dubliniensis are closely related species of C. albicans. Current phenotypic methods are not suitable to accurately distinguish all the species belonging to the C. albicans complex. Several molecular-based methods have recently been designed for discriminating among closely related Candida species. The aim of this study was to establish the prevalence of C. dubliniensis and C. africana in vulvovaginal samples with phenotypic and genotypic methods.

MATERIALS AND METHODS

We re-examined 376 vulvovaginal C. albicans complex isolates. All the isolates were identified with morphological features and HWP1 gene polymorphisms. ITS and D1/D2 sequencing, carbohydrate assimilation, MALDI-TOF MS profiles and antifungal susceptibilities were evaluated for C. africana and C. dubliniensis isolates.

RESULTS

Of the 376 isolates, three C. africana and three C. dubliniensis isolates (0.8% and 0.8% prevalence, respectively) were identified by molecular methods (HPW1, ITS and D1/D2) Phenotypically, C. africana differed from C. albicans and C. dubliniensis by formation of no/rare pseudohyphae, absence of chlamydospores and, the development of turquoise green colonies on CHROMagar. MALDI-TOF MS and API ID 32C could not revealed C. africana isolates. C. africana and C. dubliniensis isolates showed very low MIC values for all the tested antifungals.

DISCUSSION

This first report of C. africana from Turkey provides additional data for epidemiological, phenotypic features and antimicrobial susceptibility profiles. This study also highlights the importance of using genotypic methods in combination with phenotypic methods.

Fungal Profile of Vulvovaginal Candidiasis in a Tertiary Care Hospital

INTRODUCTION

Vulvovaginal Candidiasis (VVC) is a common medical health problem of adult women. It is most commonly caused by Candida albicans. But there is a change in fungal profile. Sabouraud's Dextrose Agar (SDA) is the most common culture medium used where mixed fungal infection may be missed. It can be detected easily by using chromogenic culture medium.

AIM

To know the fungal profile of vulvovaginal candidiasis using Candida CHROMagar and antifungal susceptibility pattern in patients attending tertiary care hospital.

MATERIALS AND METHODS

Culture confirmed cases of VVC presented at Department of Obstetrics and Gynaecology of Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Puducherry, India, from July 2015 to December 2015 were included in the cross-sectional study. Two high vaginal swabs were collected and inoculated on SDA and Candida CHROMagar (Hi-Media, Mumbai, India). After overnight incubation the colonies were counted and colour of the colonies were recorded from Candida CHROMagar. Candida spp. were identified by sugar fermentation and assimilation tests and other conventional tests. Antifungal susceptibility tests were performed by the disc diffusion method using fluconazole (25 μg) and voriconazole (1μg) as per the Clinical and Laboratory Standards Institute (CLSI - M44-A2) guidelines.

RESULTS

A total of 50 culture confirmed (23.7%) cases were detected from 211 clinically suspected VVC cases. Candida glabrata (45.1%) was the most common isolate, followed by Candidatropicalis (23.5%), Candida albicans (17.6%), Candida krusei (9.8%) and Candida parapsilosis (3.9%). One mixed infection of C. glabrata and C. albicans was identified on Candida CHROMagar. Mixed fungal infection was observed in 2% of positive culture and 0.5% of VVC cases. The antifungal susceptibility testing revealed that 15.7% and 9.8% isolates of Candida spp. were resistant and Susceptible Dose Dependent (S-DD) respectively to fluconazole. The increase resistant against fluconazole was because of increased isolation of C. glabrata strains. All strains of Candida spp. were susceptible to voriconazole.

CONCLUSION

C. glabrata was the most common causative agent of VVC in a tertiary care hospital. Chromogenic culture medium facilitates detection of mixed fungal infection. In vitro susceptibility testing should be used to guide the treatment especially in cases of non-albicans Candidiasis.

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.

Prevalence and antifungal susceptibility of Candida albicans and its related species Candida dubliniensis and Candida africana isolated from vulvovaginal samples in a hospital of Argentina

Candida africana taxonomical status is controversial. It was proposed as a separate species within the Candida albicans species complex; however, phylogenetic analyses suggested that it is an unusual variety of C. albicans. The prevalence of C. albicans-related species (Candida dubliniensis and C. africana) as vulvovaginal pathogens is not known in Argentina. Moreover, data on antifungal susceptibility of isolates causing vulvovaginal candidiasis is scarce. The aims of this study were to establish the prevalence of C. dubliniensis and C. africana in vaginal samples and to evaluate the antifungal susceptibilities of vaginal C. albicans species complex strains. We used a molecular-based method coupled with a new pooled DNA extraction methodology to differentiate C. dubliniensis and C. africana in a collection of 287 strains originally identified as C. albicans isolated from an Argentinian hospital during 2013. Antifungal susceptibilities to fluconazole, clotrimazole, itraconazole, voriconazole, nystatin, amphotericin B and terbinafine were evaluated by using the CLSI M27-A3 and M27-S4 documents. Of the 287 isolates, 4 C. dubliniensis and one C. africana strains (1.39% and 0.35% prevalence, respectively) were identified. This is the first description of C. africana in Argentina and its identification was confirmed by sequencing the ITS2 region and the hwp1 gene. C. dubliniensis and C. africana strains showed very low MIC values for all the tested antifungals. Fluconazole-reduced-susceptibility and azole cross-resistance were observed in 3.55% and 1.41% of the C. albicans isolates, respectively. These results demonstrate that antifungal resistance is still a rare phenomenon in this kind of isolates.

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.

Yeast species in vulvovaginitis candidosa

Introduction: Vulvovaginal candidiasis is the most common mycosis, however, the available information about antifungal susceptibilities of these yeasts is limited. Aim: To compare the gold standard fungal culture with a new molecular identification method and report the incidence of yeast species in vulvovaginitis candidosa. Method: The authors studied 370 yeasts isolated from vulvovaginal candidiasis and identified them by phenotypic and molecular methods. Results: The most common species was Candida albicans (85%), followed by Candida glabrata, and other Candida species. Conclusion: At present there are no recommendations for the evaluation of antifungal susceptibility of pathogenic fungal species occurring in vulvovaginal candidiasis and the natural antifungal resistance of the different species is known only. Matrix Assisted Laser Desorption Ionization Time of Flight identification can be used to differentiate the fluconazole resistant Candida dubliniensis and the sensitive Candida albicans strains. Orv. Hetil., 2015, 156(1), 28–31.