Detection of Candida species in vaginal samples in a clinical laboratory setting

Utility of Cand PCR in the Diagnosis of Vulvovaginal Candidiasis in Pregnant Women

Vulvovaginal candidiasis (VVC) can lead to multiple complications when it occurs during pregnancy, so it is necessary to diagnose it promptly for effective treatment. Traditional methods for identifying Candida spp. are often too time-consuming and have limited specificity and sensitivity. In this work, we evaluated the diagnostic utility of an endpoint PCR assay (Cand PCR) in vaginal swab specimens. Using a cotton swab, 108 vaginal swab samples were taken from pregnant women who consented to participate in the study. The samples were inoculated in Sabouraud agar plates (the gold standard) and subsequently used to extract DNA directly from the exudate. The yeasts isolated from the Sabouraud agar were identified in CHROMagar™ Candida. DNA extracted from vaginal swabs was amplified by Cand PCR. Based on the results of the Cand PCR and the gold standard, sensitivity (S), specificity (E), positive predictive values (PPVs), and negative predictive values (NPVs) were determined. Cand PCR presented an S = 65%, E = 100%, PPV = 100% and NPV = 91%. Cand PCR showed low sensitivity for detecting Candida spp. directly from vaginal swabs, but it was useful for identifying the etiologic agent and reducing the time to obtain the result, which is usually at least 48 h.

Prevalence and Antifungal Susceptibility of Clinically Relevant Candida Species, Identification of Candida auris and Kodamaea ohmeri in Bangladesh

Candida species are major fungal pathogens in humans. The aim of this study was to determine the prevalence of individual Candida species and their susceptibility to antifungal drugs among clinical isolates in a tertiary care hospital in Bangladesh. During a 10-month period in 2021, high vaginal swabs (HVSs), blood, and aural swabs were collected from 360 patients. From these specimens, Candida spp. was isolated from cultures on Sabouraud dextrose agar media, and phenotypic and genetic analyses were performed. A total of 109 isolates were recovered, and C. albicans accounted for 37%, being derived mostly from HVSs. Among non-albicans Candida (NAC), C. parapsilosis was the most frequent, followed by C. ciferrii, C. tropicalis, and C. glabrata. Three isolates from blood and two isolates from aural discharge were genetically identified as C. auris and Kodamaea ohmeri, respectively. NAC isolates were more resistant to fluconazole (overall rate, 29%) than C. albicans (10%). Candida isolates from blood showed 95% susceptibility to voriconazole and less susceptibility to fluconazole (67%). Two or three amino acid substitutions were detected in the ERG11 of two fluconazole-resistant C. albicans isolates. The present study is the first to reveal the prevalence of Candida species and their antifungal susceptibility in Bangladesh.

Vulvovaginal candidiasis in Iran: A systematic review and meta-analysis on the epidemiology, clinical manifestations, demographic characteristics, risk factors, etiologic agents and laboratory diagnosis

Vulvovaginal candidiasis is a global issue of concern due to its association with economic costs, sexually transmitted infections, and ascending genital tract diseases. This infection affects 75% of women on at least one occasion over a lifetime. The present systematic review and meta-analysis is the first to determine the prevalence of vulvovaginal candidiasis in Iranian women. We searched national (SID, IranDoc, Iranmedex, and Magiran) and international (PubMed, Scopus, Google Scholar, and web of science) databases for studies published between May 2000 until May 2020 reporting the epidemiologic features of vulvovaginal candidiasis in Iranian women. Inclusion and exclusion criteria were defined to select eligible studies. Data were extracted and presented according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The results of the meta-analysis were visualized as a forest plot representing the prevalence estimates of each study. Heterogeneity was also analyzed using the I², and Chi² statistics. The literature search revealed 1929 studies, of which 39 studies met the eligibility criteria, consisting of 10536 women with vulvovaginal symptoms from 24 different cities covering all parts of Iran. The city with the highest number of studies was Tehran (5/39). The overall prevalence of vulvovaginal candidiasis among Iranian women was 47% (95% CI, 0/38-0/55%) and Candida albicans was the most prevalent etiologic agent. The use of oral contraceptive pills (OCPs) was the predominant risk factor for developing vulvovaginal candidiasis and vaginal cheese-like discharges were the predominant clinical manifestation in Iranian women suffering from vulvovaginal candidiasis. The 25-34-year-old age group has the highest prevalence. A high level of I² (I² = 98.7%, P = 0.000) and Chi² (Chi² = 2993.57, P < 0.001) was obtained among studies, which provides evidence of notable heterogeneity between studies. The present meta-analysis revealed a high prevalence of vulvovaginal candidiasis in Iranian women. Given that this infection is associated with the enhanced susceptibility to sexually transmitted diseases (HIV, chlamydia, genital herpes, genital warts, gonorrhea, hepatitis, syphilis, and trichomoniasis) and also is related to the increased probability of preterm birth, congenital cutaneous candidiasis, preterm labor, and infertility, taking preventive measures such as awareness of patients as well as monitoring and controlling of the syndrome are essential.

Prevalence of Candida spp. and age-related disparities amongst women presenting with vaginitis at the Obstetrics and Gynaecology (O&G) Clinic in a Tertiary hospital in Port Harcourt, Nigeria

Background

Vaginitis, an infection of the lower genital tract in women, is known to be triggered by the overgrowth of the vagina's naturally occurring microorganisms.

Objective

This study looked at the prevalence of Candida spp. and age-related disparities amongst women presenting with vaginitis at the Obstetrics and Gynaecology (O&G) clinic in a tertiary hospital in Port Harcourt, Nigeria.

Methods

One hundred high vaginal swabs were collected from pregnant and non-pregnant women and examined microscopically and microbiologically.

Results

Age-group 20–29 years had the highest incidence of candidal vaginitis. There was a higher occurrence of yeast cells in pregnant than in non-pregnant participants while the non-pregnant women had a greater level of bacterial cells. Forty (40) of the samples contained yeasts of Candida species representing a 40% prevalence. Three species of Candida were identified with C. albicans dominating. Of the 40 samples positive for Candida spp., 30 (75.0%) were confirmed to be C. albicans. The remaining isolates were C. tropicalis (15.0%) and C. parapsilosis (10.0%).

Conclusion

The findings in this study would play a role in the future management of Candida-induced vaginitis.

Effect of Perillaldehyde on Prophylaxis and Treatment of Vaginal Candidiasis in a Murine Model

Vulvovaginal candidiasis is a common fungal infection afflicting women which is primarily caused by the yeast Candida albicans (C. albicans). It is imperative to introduce new drug classes to counter this threat due to the continuous emergence of drug-resistant cases in recent years. The purpose of this study was to clarify the in vivo antifungal activity of perillaldehyde (PAE) against C. albicans and to prove that PAE is a promising candidate for the control of vaginal candidiasis. An animal model of vaginitis was developed to demonstrate the therapeutic and preventive effects of PAE on vaginal candidiasis, and these were evaluated through fungal and histopathological examinations. In clarifying the mechanism of PAE, standard hematological test results indicated that white blood cells (WBC) were elevated abnormally in mice infected with C. albicans, whereas when the mice were treated with various concentrations of PAE, the number of WBC in the blood was reduced. Flow cytometry was used to detect the populations of neutrophils, macrophages and CD4 T cells in the vaginal tissue of the mice. PAE was found to reduce these immune cells, which all play a key role in the inflammatory response, and the related interleukin and pro-inflammatory cytokines, including IL-17, IL-22 and TNF-α. These were detected using ELISA. Finally, we detected the expression levels of E-cadherin in the PAE treatment mouse group and discovered that it had recovered to its normal levels, but in the infection mouse group, the E-cadherin expression was clearly suppressed by the presence of C. albicans. Our data demonstrated that PAE targets these cytokines and possesses the ability to fight the fungal infection while also reducing the levels of the inflammatory factors identified. Our results demonstrated that PAE has a significant preventative and therapeutic effect on vaginal candidiasis and is a potential candidate for the treatment of vaginal Candida infections.

An introduction of the role of probiotics in human infections and autoimmune diseases

During the last decades, studies exploring the role of microorganisms inhabiting human body in different scenarios have demonstrated the great potential of modulating them to treat and prevent diseases. Among the most outstanding applications, probiotics have been used for over a century to treat infections and inflammation. Despite the beneficial role of other probiotics, Lactobacillus and Bifidobacterium species are the most frequently used, and have been effective as a therapeutic option in the treatment/prevention of dental caries, periodontal diseases, urogenital infections, and gastrointestinal infections. Additionally, as gastrointestinal tract harbors a great diversity of microbial species that directly or indirectly modulate host metabolism and immune response, the influence of intestinal microbiota, one of the targets of therapies using probiotics, on the biology of immune cells can be explored to treat inflammatory disorders or immune-mediated diseases. Thus, it is not surprising that probiotics have presented promising results in modulating human inflammatory diseases such as type 1 diabetes, multiple sclerosis, rheumatoid arthritis and inflammatory bowel disease, among others. Hence, the purpose of this review is to discuss the potential of therapeutic approaches using probiotics to constrain infection and development of inflammation on human subjects.

Vulvovaginal candidiasis: species distribution of Candida and their antifungal susceptibility pattern

BACKGROUND

Vulvovaginal candidiasis is a global issue of concern due to its association with economic costs, sexually transmitted infections, and ascending genital tract infection. The aim of this study was to determine species distribution and antifungal susceptibility pattern of Candida species causing vulvovaginal candidiasis.

METHODS

A cross sectional study was conducted from November 2015 to December 2016 at the Family Guidance Association of Ethiopia. Vaginal swabs collected from study subjects that were clinically diagnosed with vulvovaginal candidiasis were cultured. Yeast identification and antifungal susceptibility testing were determined by the automated VITEK 2 compact system. The association of vulvovaginal candidiasis with possible risk factors was assessed and analyzed using SPSS version 20.

RESULTS

The overall prevalence of vulvovaginal candidiasis was 41.4%. The association of vulvovaginal candidiasis was statistically significant with previous genital tract infection (p = 0.004), number of life-time male sex partners (p = .037), and number of male sex partners in 12 month (p = 0.001). Of 87 Candida isolates recovered, 58.6% were C. albicans while 41.4% were non-albicans Candida species. The highest overall drug resistance rate of Candida species was observed against fluconazole (17.2%), followed by flycytosine (5.7%). All Candida isolates were 100% susceptible to voriconazole, caspofungin, and micafungin. C. albicans, was 100% susceptible to all drugs tested except fluconazole and flycytosine with a resistance rate of 2% each drug. C. krusei, was 100 and 33.3% resistant to fluconazole and flycytosine, respectively.

CONCLUSIONS

High prevalence rate of vulvovaginal candidiasis and observation of high prevalence rate of non-albicans Candida species in the present study substantiate, the importance of conducting continuous epidemiological surveys to measure changes in species distribution from C. albicans to non-albicans Candida species in Ethiopia. Although, fluconazole still appeared to be active against all isolates of C. albicans and non-albicans Candida species high resistance rate of C. krusei against the drug may demonstrate a search for alternative antifungal drugs when treating vulvovaginal candidiasis caused by C. krusei.

Probiotics for vulvovaginal candidiasis in non-pregnant women

BACKGROUND

Vulvovaginal candidiasis (VVC) is estimated to be the second most common form of infection after bacterial vaginosis. The ability of probiotics in maintaining and recovering the normal vaginal microbiota, and their potential ability to resist Candidas give rise to the concept of using probiotics for the treatment of VVC.

OBJECTIVES

To assess the effectiveness and safety of probiotics for the treatment of vulvovaginal candidiasis in non-pregnant women.

SEARCH METHODS

We searched the following databases to October 2017: Sexually Transmitted Infections Cochrane Review Group's Specialized Register, CENTRAL, MEDLINE, Embase and eight other databases. We searched in following international resources: World Health Organization International Clinical Trials Registry Platform, ClinicalTrials.gov, Web of Science and OpenGrey. We checked specialty journals, reference lists of published articles and conference proceedings. We collected information from pharmaceutical companies and experts in the field.

SELECTION CRITERIA

Randomized controlled trials (RCT) using probiotics, alone or as adjuvants to conventional antifungal drugs, to treat VVC in non-pregnant women. Trials recruiting women with recurrent VVC, coinfection with other vulvovaginal infections, diabetes mellitus, immunosuppressive disorders or taking immunosuppressant medication were ineligible for inclusion. Probiotics were included if they were made from single or multiple species and in any preparation type/dosage/route of administration.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for eligibility and quality and extracted data. We resolved any disagreements through consensus. The quality of the evidence was assessed using the GRADE approach.

MAIN RESULTS

Ten RCTs (1656 participants) met our inclusion criteria, and pharmaceutical industry funded none of these trials. All trials used probiotics as adjuvant therapy to antifungal drugs. Probiotics increased the rate of short-term clinical cure (risk ratio (RR) 1.14, 95% confidence interval (CI) 1.05 to 1.24, 695 participants, 5 studies, low quality evidence) and mycological cure (RR 1.06, 95% CI 1.02 to 1.10, 969 participants, 7 studies, low quality evidence) and decreased relapse rate at one month (RR 0.34, 95% CI 0.17 to 0.68, 388 participants, 3 studies, very low quality evidence). However, this effect did not translate into a higher frequency of long-term clinical cure (one month after treatment: RR 1.07, 95% CI 0.86 to 1.33, 172 participants, 1 study, very low quality evidence; three months after treatment: RR 1.30, 95% CI 1.00 to 1.70, 172 participants, one study, very low quality evidence) or mycological cure (one month after treatment: RR 1.26, 95% CI 0.93 to 1.71, 627 participants, 3 studies, very low quality evidence; three months after treatment: RR 1.16, 95% CI 1.00 to 1.35, 172 participants, one study, very low quality evidence). Probiotics use did not increase the frequency of serious (RR 0.80, 95% CI 0.22 to 2.94; 440 participants, 2 studies, low quality evidence). We found no eligible RCTs for outcomes as time to first relapse, need for additional treatment at the end of therapy, patient satisfaction and cost effectiveness.

AUTHORS' CONCLUSIONS

Low and very low quality evidence shows that, compared with conventional treatment, the use of probiotics as an adjuvant therapy could increases the rate of short-term clinical and mycological cure and decrease the relapse rate at one month but this did not translate into a higher frequency of long-term clinical or mycological cure. Probiotics use does not seem to increase the frequency of serious or non-serious adverse events. There is a need for well-designed RCTs with standardized methodologies, longer follow-up and larger sample size.

Isolation of different species of Candida in patients with vulvovaginal candidiasis from sari, iran

BACKGROUND

Vulvovaginal Candidiasis (VVC) is a frequent, complex and cumbersome condition that can cause physical and psychological distress for the involved individual. Candida albicans was reported as the most common agent of VVC yet it seems that we are recently encountering changes in the pattern of Candida species in VVC.

OBJECTIVES

In this study we assessed different species of Candida isolated from patients with VVC, residing in Sari, Iran.

PATIENTS AND METHODS

Two hundred and thirty-four patients with vulvovaginitis were enrolled in this study. Samples were collected by a wet swab. Each vaginal swab was examined microscopically and processed for fungal culture. The identification of Candida species was done by morphological and physiological methods such as culture on CHROMagar Candida media and sugar assimilation test with the HiCandida identification kit (HiMedia, Mumbai, India).

RESULTS

Out of 234 patients with vulvovaginitis, 66 (28.2%) patients showed VVC. Of these patients, 16 (24.2%) had recurrent VVC (RVVC). The age group of 20 - 29 year-olds had the highest frequency of VVC (48.5%). Erythema concomitant with itching (40.9%) was the most prevalent sign in VVC patients. Fifty-seven (86.4%) of the collected samples had positive results from both microscopic examination and culture. In total, 73 colonies of Candida spp. were isolated from 66 patients with VVC. The most common identified species of Candida were C. albicans (42.5%), C. glabrata (21.9%) and C. dubliniensis (16.4%). In patients with RVVC and patients without recurrence, C. albicans and non-albicans species of Candida were frequent species, respectively.

CONCLUSIONS

The results of our study showed that non-albicans species of Candida are more frequent than C. albicans in patients with VVC. This result is in line with some recent studies indicating that non-albicans species of Candida must be considered in gynecology clinics due to the reported azole resistance in these species.

Prevalence and risk factors for bacterial vaginosis and other vulvovaginitis in a population of sexually active adolescents from Salvador, Bahia, Brazil

Bacterial vaginosis, trichomoniasis, and genital candidiasis are considered the main etiologies of vulvovaginitis. Few studies estimate the prevalence of vulvovaginitis among adolescents, especially in Brazil. This study aimed to determine the prevalence and main risk factors associated with bacterial vaginosis and genital infection by C. albicans and Trichomonas vaginalis among a group of adolescents from Salvador, Bahia, Brazil. One hundred sexually active adolescents followed at an adolescent gynecology clinic were included. Endocervical and vaginal samples were obtained during gynecological examination. Nugent criteria were applied for the diagnosis of bacterial vaginosis. For Candida albicans and Trichomonas vaginalis detection, culture in Sabouraud agar plates and Papanicolaou cytology were used, respectively. The mean age of participants was 16.6 ± 1.6 years. The prevalence of bacterial vaginosis was 20% (95% CI 12-28) and of genital infection by Candida was 22% (95% CI 14-30). Vaginal cytology detected Trichomonas vaginalis in one patient. Alcohol, tobacco, and illegal drug use (P = 0.02) and multiple lifetime partners were statistically related to bacterial vaginosis (P = 0.01). The prevalence of bacterial vaginosis and genital candidiasis was similar to other studies carried out among adolescents worldwide.

Identification of Candida species associated with vulvovaginal candidiasis by multiplex PCR

BACKGROUND

Vulvovaginal candidiasis is a common infection. The aim of this study was to identify the species of vaginal Candida isolates by using multiplex PCR technique.

METHODS

191 isolates from patients admitted to Mahdieh hospital were identified. The vaginal swab specimens were cultured on Sabouraud Dextrose Agar. The ITS1 region between the 18S and 5.8S rRNA genes and a specific DNA fragment within the ITS2 region were amplified. The multiplex PCR products were separated by electrophoresis in 2% agarose gel, visualized by staining with ethidium bromide, and photographed. Descriptive statistics, Chi-square test, and Spearman correlation were used to summarize the findings.

RESULTS

C. albicans and C. glabrata were the most common species isolated from the specimens. A mix of C. glabrata and C. albicans was the most common mixed infection isolated from the samples. The analysis revealed a significant positive association between older age and infection with C. glabrata isolates (Spearman's rho = 0.89, P = 0.015).

CONCLUSION

Multiplex PCR is a fast, yet reliable method to identify Candida species. C. albicans and then C. glabrata are the two most common causes of vulvovaginal candidiasis. The number of mixed fungal infections is higher among Iranian population compared to international reports.

Comparison of Enzymatic Method Rapid Yeast Plus System with RFLP-PCR for Identification of Isolated Yeast from Vulvovaginal Candidiasis

OBJECTIVES

To compare two identification methods, i.e., restriction fragment length polymorphism (RFLP)-PCR analysis and enzymatic method Rapid TM Yeast Plus System to identify different species causing vulvovaginal candidiasis (VVC).

MATERIALS AND METHODS

Vaginal discharges of women who had attended the gynecology outpatient clinic of Mobini Hospital in Sabzevar, Iran were collected using cotton swabs and were cultured on Sabouraud dextrose agar. Isolated yeasts were identified by germ-tube testing and Rapid TM Yeast Plus System (Remel USA). For molecular identification, the isolated DNA was amplified with ITS1 and ITS4 universal primers and PCR products digested with the enzyme HpaІІ followed by agarose gel electrophoresis. Epidemiological and clinical features of women with respect to identified species were also evaluated.

RESULTS

Out of 231 subjects enrolled, 62 VVC cases were detected. The isolated species were identified as follows: Candida albicans, 24 (38.7%), C. glabrata, 15 (24.2%), C. kefyr, 13 (21.0%) C. krusei, 9 (14.5%), and Saccharomyces cerevisiae, 1 (1.6%) by RFLP-PCR method; whereas findings by Rapid TM Yeast Plus System were C. albicans, 24 (38.7%), C. glabrata, 5 (8%), C. kefyr, 11 (17.7%) C. krusei, 2 (3.2%), S. cerevisiae, 9 (14.5%), and C. tropicalis, 6 (9.6%) as well as other nonpathogenic yeasts, 4 (6.9%).

CONCLUSION

Statistical comparison showed that there is no significant difference in identification of C. albicans by the two methods; although, in this study, it was not true about other species of yeasts. A correlation between clinical and laboratory findings is important as it enables us to administer an appropriate treatment on time.

Candida parapsilosis: a review of its epidemiology, pathogenesis, clinical aspects, typing and antimicrobial susceptibility

The Candida parapsilosis family has emerged as a major opportunistic and nosocomial pathogen. It causes multifaceted pathology in immuno-compromised and normal hosts, notably low birth weight neonates. Its emergence may relate to an ability to colonize the skin, proliferate in glucose-containing solutions, and adhere to plastic. When clusters appear, determination of genetic relatedness among strains and identification of a common source are important. Its virulence appears associated with a capacity to produce biofilm and production of phospholipase and aspartyl protease. Further investigations of the host-pathogen interactions are needed. This review summarizes basic science, clinical and experimental information about C. parapsilosis.

Candida albicans and filtrates interfere with human spermatozoal motility and alter the ultrastructure of spermatozoa: an in vitro study

The in vitro effects of Candida albicans and its filtrates on the motility and ultrastructure of human spermatozoa from healthy donors were studied. A significant reduction in sperm progressive motility and signs of membrane alteration, directly related to contact time were observed. Distinct adhesion of spermatozoa to C. albicans and agglutination were observed. Light and transmission electron microscopy examinations showed that spermatozoa attached to C. albicans mainly via the head. Multiple ultrastructural lesions were present, which were the possible morphological reasons for spermatozoan immobilization observed in the present study. It is concluded that C. albicans as well as its filtrates had an inhibitory effect on human sperm motility and impaired the ultrastructure of human spermatozoa, which could be associated with male infertility.

Vulvovaginal candidosis

Despite therapeutic advances, vulvovaginal candidosis remains a common problem worldwide, affecting all strata of society. Understanding of anti-candida host defence mechanisms in the vagina has developed slowly and, despite a growing list of recognised risk factors, a fundamental grasp of pathogenic mechanisms continues to elude us. The absence of rapid, simple, and inexpensive diagnostic tests continues to result in both overdiagnosis and underdiagnosis of vulvovaginal candidosis. I review the epidemiology and pathogenesis of this infection, and also discuss management strategies.

Antimicrobial effects of liquid anesthetic isoflurane on Candida albicans

Candida albicans is a dimorphic fungus that can grow in yeast morphology or hyphal form depending on the surrounding environment. This ubiquitous fungus is present in skin and mucus membranes as a potential pathogen that under opportunistic conditions causes a series of systemic and superficial infections known as candidiasis, moniliasis or simply candidiasis. There has been a steady increase in the prevalence of candidiasis that is expressed in more virulent forms of infection. Although candidiasis is commonly manifested as mucocutaneous disease, life-threatening systemic invasion by this fungus can occur in every part of the body. The severity of candidal infections is associated with its morphological shift such that the hyphal morphology of the fungus is most invasive. Of importance, aberrant multiplication of Candida yeast is also associated with the pathogenesis of certain mucosal diseases. In this study, we assessed the anti-candidal activity of the volatile anesthetic isoflurane in liquid form in comparison with the anti-fungal agent amphotericin B in an in vitro culture system. Exposure of C. albicans to isoflurane (0.3% volume/volume and above) inhibited multiplication of yeast as well as formation of hyphae. These data suggest development of potential topical application of isoflurane for controlling a series of cutaneous and genital infections associated with this fungus. Elucidiation of the mechanism by which isoflurane effects fungal growth could offer therapeutic potential for certain systemic fungal infections.

Sexually transmitted infections: screening, syndromes, and symptoms

STI are among the most common pathological conditions affecting sexually active adolescents. Both screening of asymptomatic adolescents and a thoughtful, thorough approach to the evaluation of symptoms are critical measures in STI identification and control.