Antifungal Susceptibility Testing Research Articles

Evaluation of Antifungal Activity of Psidium guajava (Guava) Leaf Extracts

Aims: This study aimed to evaluate the effectiveness of four Psidium guajava leaf extracts against three strains of Candida albicans and a strain of Cryptococcus neoformans. Study Design: Experiment-observational study. Place and Duration of Study: P. guajava leaves were collected from specific areas in Regions Three and Four in Guyana; and the preparation of the leaf extracts and the treatment against the fungi were performed in two laboratories at the University of Guyana from August 2022-September 2023. Methodology: P. guajava leaves were washed with water, air-dried at room temperature, and ground in a disinfected food mixer. Extracts were prepared by soaking the ground leaves in different solvents, and then using the rotary evaporator to reduce the solutions and obtain crude extracts. Filter paper discs were prepared and allowed to soak in various concentrations of the crude extracts. The discs were then subjected to antifungal susceptibility testing on Potato Dextrose agar seeded with an appropriate fungus according to Clinical Laboratory Standards Institutes guidelines. The plates were incubated and the zone of inhibition (ZOIs) was measured. Results: P. guajava leaves were effective against all four strains of fungi evaluated. The largest ZOI was observed for C. neoformans (25 mm) with the ethyl acetate extract at 100 mg/mL concentration. Large ZOI was also observed for the three strains of C. albicans (10-15 mm). For one of the C. albicans strains, a ZOI significantly higher than the antifungal agents (ketoconazole and fluconazole) was observed with the P. guajava ethyl acetate extract at 100 mg/mL. Conclusion: It can be concluded that P. guajava leaves have antifungal activity against C. albicans and C. neoformans, potentially greater than current antifungal agents like ketoconazole and fluconazole.

Integrating Clinical and Microbiological Expertise to Improve Vaginal Candidiasis Management.

Vaginal candidiasis (VC) is a prevalent condition among women of reproductive age and poses a significant global public health challenge. However, the disease is often diagnosed and treated without mycological information. We investigated the epidemiology, laboratory diagnostics, and antifungal susceptibility of VC. We included 300 women from Çukurova University Obstetrics and Gynecology outpatient clinic in Adana, Türkiye. Participants underwent a health survey and provided vaginal swab samples for microscopic examination and fungal culture. The microscopic analysis involved wet-mount and gram-stained slides, whereas fungal identification involved CHROMAgar Candida, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), and real-time polymerase chain reaction high-resolution melting analysis (RT-PCR HRMA). Antifungal susceptibility tests were conducted at pH 7 and 4 using the CLSI document M44-A2. Of the 106 women with positive fungal cultures, 86.8% were diagnosed with VC, whereas 13.2% showed Candida colonization. Among those with VC, 55.4% had acute and 44.6% had recurrent VC; a family history of allergies increased the risk for both types. We recovered 115 yeast isolates, predominantly C. albicans, C. glabrata, and C. krusei. Diagnostic accuracy of CHROMAgar Candida was 91.3% for the most common isolates, and HRMA was consistent in differential diagnosis. Antifungal resistance varied with pH; susceptibility to fluconazole, itraconazole, and ketoconazole decreased at pH 4, whereas susceptibility to miconazole increased. Our findings underscore the need for a diagnostic algorithm and enhanced collaboration between clinicians and microbiologists to improve VC management. Recommendations include using Gram staining, CHROMAgar Candida, MALDI-TOF MS, and antifungal susceptibility tests at both pH levels.

Fusarium spp. Causing invasive disease in humans: a case series from north India.

Owing to their inherent resistance to different classes of antifungals, early identification of Fusarium spp. is crucial. In this study, ten clinical isolates were included from patients with invasive fusariosis involving lungs, sinuses or both. Clinico-radiological data were collected. Samples were processed by standard laboratory procedures. Three gene regions (ITS, TEF1 and RPB2) were amplified by PCR for multilocus sequencing. Fusarium MLST, FUSARIUM-ID and FUSARIOID-ID databases were used for final identification. Antifungal susceptibility testing was performed by broth microdilution following CLSI M38-A3 and Sensititre™ YeastOne™ YO9 plate. Pulmonary involvement was seen in all patients, and sino-nasal involvement was present in six. Radiologically, consolidations and cavitations were present in eight and six cases respectively. Halo sign was present in six; reverse halo sign was also found in three of them. Direct microscopy showed septate hyphae that were morphologically different from those found in aspergillosis. Results of the molecular identification were as follows: 2 F. irregulare, 1 F. pernambucanum, 1 F. incarnatum, 1 F. sp. FIESC 30, 2 F. keratoplasticum, 1 F. falciforme, 1 F. pseudonygamai and 1 F. delphinoides. For both Fusarium solani (FSSC) and Fusarium incarnatum-equiseti (FIESC) species complexes, amphotericin B had lowest minimum inhibitory concentrations (MICs). Importantly, for terbinafine, all FIESC isolates had low MICs while FSSC isolates had high MICs. In some cases, early identification of Fusarium spp. is possible by means of morphology of hyphae on direct microscopy and findings on radiology. Molecular identification at least to the species complex level is crucial for choice of antifungals.

Multicentre Study of Candida parapsilosis Blood Isolates in Türkiye Highlights an Increasing Rate of Fluconazole Resistance and Emergence of Echinocandin and Multidrug Resistance.

Worldwide emergence of clonal outbreaks caused by fluconazole-resistant (FLCR) and the recent emergence of echinocandin- and multidrug-resistant (ECR and MDR) Candida parapsilosis isolates pose serious threats to modern clinics. Conducting large-scale epidemiological studies aimed at determining the genetic composition and antifungal resistance rates is necessary to devise antifungal stewardship and infection control strategies at international, national and local levels. Despite being severely hit by outbreaks due to FLCR C. parapsilosis isolates, such knowledge at the national level is lacking in Türkiye. Herein, we conducted a prospective multicentre study involving five major clinical centres in Türkiye to determine antifungal resistance rates, underlying mechanisms and genetic composition of all isolates. In total, 341 isolates were collected from 265 patients including clinical information. Antifungal susceptibility testing against common antifungals was performed in addition to sequencing of ERG11 and FKS1. Last, isolates were genotyped with short tandem repeat (STR) genotyping to investigate potential nosocomial transmission. The FLCR rate was 26.7% (91/341), out of which 75.8% (69/91) harboured the ERG11Y132F mutation. Patients infected with FLCR isolates had a higher mortality rate compared to their susceptible counterparts (49% for FLCR vs. 42% for susceptible). ECR rate was 2.1% (7/341) and isolates carried FKS1F652L/R658G/W1370R mutations. Concerningly, four ECR isolates were MDR. FLCR isolates grouped in distinct clusters without evidence of inter-hospital transmission, whereas large clusters containing susceptible isolates from all centres were noted. Overall, the increasing prevalence of FLCR C. parapsilosis at national level and the emergence of ECR and MDR isolates pose serious clinical challenges in Türkiye. Therefore, conducting large-scale epidemiological studies are critical to determine the trend of antifungal resistance and to tailor pertinent antifungal stewardship and infection control strategies to effectively curb the spread of drug-resistant C. parapsilosis.

Genomic Assessment of Resistance of Invasive Fungal Infections in Immunocompromised Patients

Introduction: Invasive fungal infections (IFIs) are emerging and significantly increased in immunocompromised populations. These infections are the most commonly acquired by inhalation of spores and can be transmitted by percutaneous inoculation in cutaneous and subcutaneous infections. Candida and Aspergillus species remain the most common cause of invasive fungal infections including neutropenia, hematological malignancies, bone marrow transplantation, parenteral nutrition prolonged treatment with corticosteroids, chemotherapy, HIV infection, invasive medical procedures, and the newer immune suppressive agents. Materials and Methods: An observational study was carried out at SRM MCH&RC, Tamil Nadu, India, in January 2020. Invasive fungal infections were identified in conventional methods (KOH, Gram staining, culture, sugar assimilation, sugar fermentation, LPCB). Antifungal susceptibility testing was done as per standard guidelines; the resistant species were subjected to molecular testing to identify the gene. Results: Clinical samples are collected from the various departments (blood, pus, tissues, BAL, pleural fluid, and other body fluids). Out of 110 clinical samples, 16 samples were positive for yeast infections and five were positive for moulds. Eighty-nine samples were negative for fungal infection. Among yeast isolates, Candida tropicalis (37%) was the most common in the study population, followed by C albicans (25%), C krusei (19%), C.glabrata (13%), and C.parapsilosis (6%). Among the filamentous fungi, all the isolates were present in the same prevalence. Some of the Candida spp. were found to be resistant to amphotericin B (2), fluconazole (2), and itraconazole (1). All moulds were found to be sensitive to the tested antifungals by microbroth dilution methods. Among the resistant Candida, spp.ERG11 gene was found to be common. Conclusion: We observed that the early detection of etiological agents by microscopy and culture and prompt initiation of antifungal therapy can aid in the reduction of morbidity and mortality among immunocompromised patients.

Clonal outbreak of Candida vulturna in a paediatric oncology ward in Maranhão, Brazil

ObjectiveTo describe an outbreak due to Candida vulturna, a newly emerging Candida species belonging to the Candida haemulonii species complex in the Metschnikowiaceae family. MethodsIn this retrospective cohort study we genotyped 14C. vulturna bloodstream isolates, occurring in a 4-month-period in paediatric cancer patients in a Brazilian hospital. To prove an outbreak, ITS sequence analysis and whole genome sequencing (WGS) was done. Antifungal susceptibility was performed with the reference CLSI method and the commercial Sensititre YeastOne (SYO) YO10 plates. A control C. vulturna isolate from another region in Brazil was included in all analyses. ResultsMALDI-TOF-MS identified isolates as C. pseudohaemulonii and C. duobushaemulonii albeit with low scores and therefore molecular methods were required for accurate identification. ITS sequence analyses clearly differentiated C. vulturna from other species in the C. haemulonii species complex. WGS proved the presence of a clonal outbreak with C. vulturna involving 14 paediatric patients. Antifungal susceptibility testing (AFST) with two methods showed the isolates had low MICs of commonly available antifungals. ConclusionThis study describes an outbreak due to the rare yeast C. vulturna, related to C. auris, during a four-month period in patients admitted to a paediatric oncology ward in a Brazilian hospital. In contrast to previous studies the yeast was susceptible to all antifungals and patient outcome was good.

Antifungal resistance, clinical outcome and clinico-microbiological correlation in ocular infections due to common melanized fungi Curvularia lunata and Lasiodiplodia theobromae in South India.

Aim. Melanized fungi were rarely studied for their antifungal resistance (AFR) or clinical outcome, despite rising incidence of melanized fungal ocular infections and AFR in general. We report the antifungal resistance patterns, clinical outcome and clinico-microbiological correlation in two commonly isolated melanized fungi from ocular infections, Curvularia lunata and Lasiodiplodia theobromae, at a tertiary eyecare centre in South India.Gap statement. Despite melanized fungi accounting for a significant proportion of ocular fungal infections in the Indian subcontinent, and despite there being a limited selection of effective antifungal agents available for these infections, the existing data and studies on these issues remain sparse. Therefore, this study aimed to investigate the prevalence of antifungal resistance in two of the most common melanized fungal pathogens in ocular infections, Curvularia lunata and Lasiodiplodia theobromae and correlate it with the treatment given and the clinical outcome in patients.Methodology. Electronic medical records provided the clinical data. Standard broth microdilution was performed for antifungal susceptibility testing (AFST) in 30 isolates (17 C. lunata and 13 L. theobromae) for amphotericin B and natamycin (polyenes): voriconazole, ketoconazole, posaconazole, itraconazole and fluconazole (azoles) and caspofungin (echinocandin). Multidrug resistance (MDR) was defined as resistance to more than or equal to two classes of antifungals. DNA sequencing was performed for the isolates for species confirmation. The multivariate analysis was done for determining poor prognostic factors.Results. AFST showed highest susceptibility of study isolates for voriconazole (83.3% isolates), followed by natamycin (80%), fluconazole (80%), itraconazole (76.7%), ketoconazole (70%), posaconazole (66.7%), caspofungin (66.7%) and lastly amphotericin B (63.3%). All patients empirically received topical natamycin; additional oral ketoconazole/intraocular voriconazole was administered in select few. MDR was strongly associated with poor clinical outcome (multivariate analysis: P = 0.03, odds ratio = 7.8). All patients had microbial keratitis, one progressed to endophthalmitis. Additionally, therapeutic penetrating keratoplasty was required in 40% of cases. Globe salvage was possible in 80% patients, though good visual outcome was seen in only half of them. Both, anatomical and visual outcomes, were poor in 20% of patients. DNA sequencing showed C. lunata as the highest study species.Conclusion. C. lunata and L. theobromae showed varying in vitro antifungal susceptibility and clinical outcome in ocular infections. Voriconazole had significantly higher activity, while amphotericin B had lower activity in vitro for these melanized fungi. MDR isolates showed poorer clinical outcome.

Spectrum and Antifungal Drug Resistance among Fungal Pathogens Isolated from Prison Inmates in Nairobi, Kenya

Background The emergence of antifungal resistance in fungal pathogens highlights the need for local epidemiological data to guide empirical therapy in clinical settings. Fungal research and anti-fungal drug resistance studies are limited in developing countries; hence, there is a need for burden estimation in low- and middle-income countries. This study aimed to determine the spectrum of fungal pathogens and the anti-fungal resistance profile of fungal pathogens isolated from the respiratory and urinary tracts of prison inmates in Nairobi, Kenya. Methods A cross-sectional study was conducted in which sputum and urine samples were obtained from inmates presenting with symptoms of respiratory and urogenital infections at a prison outpatient clinic. One hundred and sixty-two samples were collected and subjected to fungal investigation using standard protocols. Susceptibility to fluconazole, itraconazole, and voriconazole was assessed using standard broth microdilution. Clinical and sociodemographic data were obtained using a structured questionnaire. Results From the 162, 94 samples were positive for fungal pathogens, with an overall prevalence of 58%. Seventeen (18%) of the isolated fungi were Aspergillus fumigatus, Aspergillus flavus and Histoplasma. There was a statistically significant difference between fungal pathogens isolated from the respiratory and urogenital tracts in both sexes (p<0.05). Antifungal susceptibility testing against itraconazole showed 2 of Aspergillus flavus and Aspergillus fumigatus were resistant. Conclusion Mycological agents are significant causes of respiratory and UTI infections among prison inmates, which could be attributed to prison conditions and misdiagnosis as bacterial infections. This highlights the need for specific control measures to reduce exposure to fungal infections in prisons and in the general population.

Characterization of Yeast Isolated from the Gut Microbiota of Tunisian Children with Autism Spectrum Disorder

Research on the microbiota–gut–brain axis in autism has primarily focused on bacteria, with limited attention to fungi. There is a growing interest in understanding the involvement of fungi, particularly Candida, in patients with autism spectrum disorder. The aim of this study was to assess the prevalence, antifungal susceptibility profiles and virulence factors of Candida isolates from the guts of Tunisian children with autism. Twenty-eight children with autism and forty-six controls were enrolled. Candida isolates from the faecal samples were identified using biochemical and molecular methods; antifungal susceptibility testing was determined by the EUCAST broth microdilution method and virulence factors, including biofilm formation, cell surface hydrophobicity and phospholipase and proteinase activities, were assessed in vitro. As a result, Candida was detected in 13 children with autism (46.4%) and 14 control children (30.4%). Candida albicans was found to be the most common species isolate in the faeces of both groups of children. Antifungal susceptibility profiles showed that one Candida isolate was resistant to amphotericin B and anidulafungin (3.7%), six were resistant to micafungin (22.2%) and five were resistant to fluconazole (18.5%). All Candida isolates were biofilm producers. Of the twenty-seven isolates, only four showed phospholipase activity (14.8%), eight showed aspartyl-proteinase activity (29.6%) and nine were hydrophobic (33.3%). These results highlight the presence of Candida in the guts of children with autism, as well as the ability to express multiple virulence factors and the antifungal resistance, and they emphasize the need for further studies to confirm intestinal Candida colonization and its potential role in autism.

Diversity and Antifungal Susceptibilities of Yeasts from Mangroves in Hong Kong, China-A One Health Aspect.

While mangrove ecosystems are rich in biodiversity, they are increasingly impacted by climate change and urban pollutants. The current study provides first insights into the emergence of potentially pathogenic yeasts in Hong Kong's mangroves. Sediment and water samples were collected from ten urban and rural mangroves sites. Initial CHROMagarTM Candida Plus screening, representing the first application of this differential medium for water and soil samples collected from a non-clinical environment, enabled the rapid, preliminary phenotypic identification of yeast isolates from mangroves. Subsequent molecular profiling (ITS and/or 28S nrDNA sequencing) and antifungal drug susceptibility tests were conducted to further elucidate yeast diversity and drug resistance. A diversity of yeasts, including 45 isolates of 18 distinct species across 13 genera/clades, was isolated from sediments and waters from Hong Kong mangroves. Molecular profiling revealed a dominance of the Candida/Lodderomyces clade (44.4%), a group of notorious opportunistic pathogens. The findings also reveal a rich biodiversity of non-Candida/Lodderomyces yeasts in mangroves, including the first reported presence of Apiotrichum domesticum and Crinitomyces flavificans. A potentially novel Yamadazyma species was also discovered. Remarkably, 14.3% of the ubiquitous Candida parapsilosis isolates displayed resistance to multiple antifungal drugs, suggesting that mangroves may be reservoirs of multi-drug resistance. Wildlife, especially migratory birds, may disseminate these hidden threats. With significant knowledge gaps regarding the environmental origins, drug resistance, and public health impacts of pathogenic yeasts, urgent surveillance is needed from a One Health perspective. This study provides an early warning that unrestrained urbanization can unleash resistant pathogens from coastal ecosystems globally. It underscores the necessity for enhanced surveillance studies and interdisciplinary collaboration between clinicians, ornithologists, and environmental microbiologists to effectively monitor and manage this environmental health risk, ensuring the maintenance of 'One Health'.

Distribution and antifungal susceptibility profiles of Candida species isolated from candidemia patients admitted to Egyptian tertiary hospitals: a cross-sectional study

BackgroundCandidemia is a widespread threat that can lead to significant complications in healthcare settings.ObjectivesOur study aimed to identify isolates of Candida isolated from blood culture bottles of patients with candidemia and assess their antifungal susceptibility profiles.MethodsWe conducted a cross-sectional study at Cairo University tertiary care hospitals over 16 months including 90 patients. Candida isolates were collected from blood culture bottles, and identified using MALDI-TOF MS technology of VITEK MS PRIME (bioMérieux) with the corresponding database VITEK IVD Database 3.2. followed by antifungal susceptibility testing using VITEK 2 Compact system.ResultsCandida albicans was the most common species isolated from both pediatric and adult patients with percentages of 47.3% and 36.4% respectively, followed by Candida parapsilosis with percentages of 32.6% and 25.0% respectively. Voriconazole showed the highest antifungal activity at 90.9% of isolates in adults and 95.7% in pediatrics, followed by caspofungin and micafungin. The mean hospital stays for adults ranged from 8 to 30 days and from 10 to 42 days in the pediatric group.ConclusionsC. albicans remains the predominant species isolated from both pediatric and adult candidemia patients, despite a notable increase in other species. C. tropicalis and C. parapsilosis are considered the most common non-albicans Candida (NAC) species. The rise in Candida species other than albicans highlights the urgent need for effective antifungal stewardship programs. Voriconazole exhibited the higher antifungal activity followed by caspofungin and micafungin.

Comparative evaluation of MIC values of Trichosporon spp. by MTT assay and CLSI M27-A3 broth microdilution reference methods

Objectives: The objective of this study was to determine and compare the minimum inhibitory concentration (MIC) values of Trichosporon spp. by MTT (3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl- 2H-tetrazoliumbromide) assay, and Clinical and Laboratory Standards Institute M27-3rd edition (CLSI M27-A3) broth microdilution methods. Materials and Methods: Antifungal susceptibility testing was done by CLSI M27-A3 broth microdilution and MTT assay for all the 72 Trichosporon isolates after genus specific and Trichosporon asahii specific polymerase chain reaction (PCR). Candida krusei ATCC 6258 was used as the reference strain. Statistical Analysis: All statistical data were analyzed using the Statistical Package for the Social Sciences, version 17 for Microsoft Windows. The percentage of agreement was calculated using the Type C intraclass correlation coefficient. Results: The MICs by MTT assay strongly correlated with those obtained by CLSI M27-A3 method, by being either the same or within 1 dilution of MIC by CLSI method. Furthermore, the ranges of MICs obtained by MTT and CLSI method were all identical in our study. The overall agreement between the two methods for the Trichosporon isolates was good, that is, 90.8% in our study. Conclusions: MTT assay can be an alternative method that assists reading of MICs visually with a colored end point, making it easier compared to CLSI M27-A3 method. MTT assay can also be standardized for other yeasts and molds so that antifungal susceptibility tests can be done for different fungi.

Standardisation of high throughput microdilution antifungal susceptibility testing for Candida albicans and Cryptococcus neoformans.

The Clinical and Laboratory Standards Institute (CLSI) M27 guidelines are the recommended and most commonly used protocols for broth microdilution antifungal susceptibility testing of yeasts. However, these guidelines are limited to the use of 96-well assay plates, limiting assay capacity. With the increased risk of fungal resistance emerging in the community, it is important to have alternative protocols available, that offer higher throughput and can screen more than eight to ten potential antifungal compounds per plate. This study presents an optimised broth microdilution minimum inhibitory concentration (MIC) method for testing the susceptibility of yeasts in an efficient high throughput screening setup, with minimal growth variability and maximum reproducibility. We extend the M27 guidelines and optimise the conditions for 384-well plates. Validation of the assay was performed with ten clinically used antifungals (fluconazole, amphotericin B, 5-fluorocytosine, posaconazole, voriconazole, ketoconazole, itraconazole, caspofungin diacetate, anidulafungin and micafungin) against Candida albicans and Cryptococcus neoformans.

SPECIES IDENTIFICATION AND IN VITRO ANTIFUNGAL SUSCEPTIBILITY TESTING OF ASPERGILLUS ISOLATED FROM VARIOUS CLINICAL SAMPLES

Objectives: Aspergillus is ubiquitous mold species present in environment in the form of spores. Infection due to Aspergillus is uncommon in immunocompetent individuals unless they possess any abnormality or have undergone any treatment with corticosteroids. In immunocompromised individuals, infection by this fungus is common among people with prolonged neutropenia, transplants, and human immunodeficiency virus infection. The symptoms are diverse, ranging from allergic reactions to invasive aspergillosis and life-threatening complications. The aim of this study is to isolate and identify Aspergillus species obtained from various clinical specimens and perform antifungal susceptibility testing (AFST). Methods: A total of 200 isolates in which positive direct microscopic findings correlated well with culture growth for Aspergillus were included. Antifungal susceptibility was performed by micro broth dilution technique according to clinical laboratory standard institute M38-A2 guidelines. Results: Aspergillus flavus was found to be predominant species followed by Aspergillus fumigatus. AFST was performed, where all Aspergillus strains exhibited low minimum inhibitory concentration (MIC) and minimum effective concentration (MEC) values for most of antifungal drugs tested except for one strain of A. flavus, which exhibited high MIC for voriconazole and high MEC for caspofungin. Conclusion: Polyenes, azoles, and echinocandin resistance are emerging in many parts of the world. Therefore, continued application of AFST combined with morphological characterization for species identification is critical in detecting the emergence of resistance among various Aspergillus species to reduce mortality, morbidity, and overcome treatment failure.

Antifungal susceptibility, molecular epidemiology, and clinical risk factors of Candida glabrata in intensive care unit in a Chinese Tertiary Hospital.

The increasing incidence and high mortality rate of Candida glabrata infection in ICU patients is an important issue. Therefore, it is imperative to investigate the antifungal susceptibility profiles and epidemiological characteristics in local regions. Herein, antifungal susceptibility testing was conducted to determine the minimum inhibitory concentrations (MICs) of eight antifungal drugs. Multilocus sequence typing (MLST) was used to study the strain genotype, geographical distribution, and susceptibility to antifungal agents among C. glabrata isolates. The mechanism of echinocandin resistance was explored by sequencing the FKS1 and FKS2 genes (encoding 1,3-β-D-glucan synthases) of echinocandin-resistant C. glabrata strains. Moreover, we further investigated the clinical manifestations and the various risk factors of patients infected with C. glabrata in the ICU. We selected 234 C. glabrata isolates from 234 patients in the ICU randomly for the follow-up study. Cross-resistance was found among the ICU C. glabrata isolates. Analysis using MLST showed that the genetic diversity among the C. glabrata isolates was low. Furthermore, sequence type showed no correlation with the antifungal resistance profiles, but was associated with geographical distribution. We also revealed novel mutations in FKS1 (S629P) and FKS2 (W1497stop) that mediated high-level echinocandin resistance (MIC >8 µg/mL). More than 14 days' stay in ICU (P=0.007), Acute Physiology and Chronic Health Evaluation II (APACHE-II) score (P=0.024), prior antifungal exposure (P=0.039) and lung disease (P=0.036) were significantly associated with antifungal resistant/non-wild-type C. glabrata infection. Our study shed light on the antifungal susceptibility, molecular epidemiology, and clinical risk factors of C. glabrata in the ICU of a Chinese Tertiary Hospital. Importantly, we revealed the molecular mechanism of echinocandin resistance. These results highlight the significance of continued surveillance in ICUs and provide data support for the treatment of C. glabrata in clinics.

Vulvovaginal candidiasis in pregnant women attending a tertiary care centre in North-Eastern India

BackgroundCandida colonisation in vagina was found to be 20 %, rising to 30 % during pregnancy. According to studies, the prevalence of VVC during pregnancy is higher than healthy women. During pregnancy, candidal colonisation increases, both symptomatic and asymptomatic. However, the difference between strains causing symptomatic infection and those that cause asymptomatic infection is unknown. ObjectiveThis study aimed to compare the virulence factors of Candida VVC isolates from symptomatic and asymptomatic pregnant women. MethodsThe study included 120 pregnant women- 60 symptomatic and 60 asymptomatic, who presented to the Obstetrics and Gynaecology Outpatient Department with vaginitis symptoms. High vaginal swabs from the patient and used for gram stain, direct wet mount, pH detection and fungal culture in SDA with and without antibiotics. Germ tube tests, growth in CMA, and HiCrome Candida Differential Agar were used to identify yeast colonies grown in culture. The isolates were then examined for virulence factors like biofilm formation, phospholipase, coagulase, and hemolysin. Antifungal susceptibility was determined using E-test. ResultsThe current study reveals a high prevalence of Vulvovaginal Candidiasis in pregnant women(35 %). Asymptomatic patients had lower proportion of VVC than symptomatic patients. Non albicans Candida(NAC) outnumbered Candida albicans. Although Candida albicans growth was predominant in asymptomatic patients. Virulence studies revealed that Candida spp. isolated from symptomatic patients expressed a higher proportion of virulence factors. Besides NAC has higher proportion of expressing virulence factors than Candida albicans and has higher propensity to cause infection especially in symptomatic pregnant women. Antifungal susceptibility testing shows Itraconazole to be most sensitive for VVC treatment but Candida albicans was most susceptible to fluconazole while NAC had the least. ConclusionsThe study emphasizes the importance of routine screening of symptomatic pregnant women for VVC, as syndromic treatment will increase antifungal resistance, particularly in NAC.

Antifungal susceptibility and biofilm production of Candida species- causative agents of female genital tract infections.

Recurrent vulvovaginal candidosis (RVVC) is a chronic infection affecting 8-10% of women worldwide. Biofilm production of the infecting species and reduced sensitivity to antimycotics could contribute to the recurrence of this infection. This study aimed to examine the biofilm production ability and antifungal susceptibility of genital yeast isolates to determine their virulence potential. Matrix-assisted laser desorption in ionization-time of flight mass spectrometry (MALDI-TOF MS) was used to identify 300 Candida species. Using crystal violet method, strains were categorized into non-producers, weak, moderate, and strong biofilm producers (BFP). Antifungal susceptibility testing was performed using commercial Integral System YEASTS Plus test (ISYPT) and broth microdilution method (BMM). MALDI-TOF MS identified 150 Candida albicans, 124 non-albicans Candida (NAC), and 26 Saccharomyces cerevisiae strains. Within 138 (46.0%) BFP, 23 (16.7%) were strong, 44 (31.9%) moderate, and 71 (51.4%) weak. BMM was done for 43 BFP selected isolates with nystatin MIC ˃1.25 μl, fluconazole MIC ˃64 μl, and clotrimazole MIC ˃1.0 μl determined by ISYPT. Compared to all examined isolates, BMM confirmed that: i) C. albicans and NAC BFP showed low sensitivity to fluconazole (12% and 4%, respectively); ii) all BFP showed low sensitivity to nystatin (12.7% C. albicans, 14.5% NAC, and 23.1% S. cerevisiae); iii) clotrimazole in vitro was the most efficient regarding C. albicans and S. cerevisiae strains, but in 4.0% NAC BFP for this antimycotic higher MIC was established. Novel antimycotics or possible combinations of antifungal agents and natural products could be a new treatment option for RVVC.

Evaluation of a customised Sensititre YeastOne plate containing isavuconazole for antifungal susceptibility testing in Singapore

This study evaluated the performance of a customised Sensititre YeastOne (SYO) plate including isavuconazole (YIT) against existing practice (comprising SYO YO10 plate and isavuconazole gradient strip) in order to streamline the workflow for antifungal susceptibility testing in a tertiary hospital in Singapore.A total of 101 (51 yeast and 50 mould) clinical isolates were included for analysis. Isolates included in the study were recovered from a variety of body sites and reflected the case mix encountered in daily practice. Antifungal susceptibility testing was performed using three methods: YO10, YIT and gradient diffusion strip (for isavuconazole only). Reproducibility, essential agreement and categorical agreement were calculated.When YO10 and YIT plates were compared, the reproducibility was 100% for 8 common antifungals. The categorical agreement (CA) was >97% for all antifungals except for amphotericin B (89.4%), but this was attributed to seven isolates with MICs bordering the wild-type (WT) cut-off. The essential agreement (EA) obtained when testing isavuconazole using YIT versus gradient diffusion was 77.2% overall, 90.2% for yeasts and 64% for moulds.In conclusion, the YIT plate is suitable for antifungal susceptibility testing of yeasts in our laboratory. Its use for mould isolates needs to be monitored further.

Strengthening Fungal Infection Diagnosis and Treatment: An In-depth Analysis of Capabilities in Honduras.

Invasive fungal infections (IFIs) are a major public health concern in low- and middle-income countries (LMICs) due to limited diagnostic and treatment resources, leading to high morbidity and mortality. Despite their significant global burden, IFIs are underrecognized and underdiagnosed in LMICs. This study evaluates the diagnostic and therapeutic capacities for managing IFI in Honduras, a country with unique health care challenges. From March to December 2023, a comprehensive survey was conducted across multiple health care centers in Honduras. The survey, reviewed for content and clarity by local medical institutions, targeted medical microbiologists and clinicians to assess various aspects of fungal disease diagnosis and treatment. Data included the availability and use of diagnostic tools and antifungal therapies, identifying gaps and limitations in current practices. The survey revealed that Candida spp (97.4%) and Aspergillus spp (35.9%) were the most concerning pathogens. Although microscopy and culture methods were available in most institutions, their application in suspected IFI cases was inconsistent, and antifungal susceptibility testing was rarely performed. Advanced diagnostic techniques, such as antigen detection, were available in only a few institutions, while antibody detection and polymerase chain reaction testing were entirely absent. All hospitals had access to at least 1 triazole antifungal, typically fluconazole, but there was a notable scarcity of more potent antifungals, including amphotericin B formulations and echinocandins. The limited use of available diagnostic tools and the restricted availability of essential antifungals were identified as major barriers to effective IFI management. This study highlights significant gaps in the diagnostic and therapeutic capabilities for managing IFI in Honduras. The underutilization of basic diagnostic tools, the inaccessibility of advanced testing methods, and the limited availability of essential antifungal medications underscore the urgent need for capacity-building initiatives, infrastructure improvements, and policy reforms. Addressing these deficiencies is critical for enhancing the management of IFI in Honduras, with broader implications for similar LMIC settings. These findings can inform targeted interventions and resource allocation to improve outcomes for patients with IFI.

Antifungal resistance profile and genetic relatedness of moulds from rural groundwater sources

Antifungal resistance remains a significant public health threat, yet poorly investigated. This study for the first time investigated the antifungal profile of moulds isolated from groundwaters in a rural community of Osun State, Southwest Nigeria. Groundwater samples were collected during dry and rainy seasons, and processed for mould isolation using standard methods. The isolates were presumptively identified and screened for in vitro susceptibility using 4 antifungals conventionally employed in clinical cases. Multiple antifungal resistance phenotypes and indices were equally evaluated. Representative of each putatively identified species were confirmed using molecular techniques. A total of 29 and 27 moulds were obtained during the dry and rainy seasons, respectively. Genus Aspergillus was the most prevalent (30.4%). Of the 56 isolates subjected to antifungal susceptibility testing, 55(98%) were resistant to fluconazole, followed by flucytosine 49(88%), ketoconazole 45(80%) and amphotericin B 31(55%). Exactly 46 isolates were multidrug-resistant, 23(50%) each, to 3 and 4 drugs, respectively. The multiple antifungal resistance index (MARI) evaluated was 1 in all the samples A-Q, except C (0.75), transcending the threshold limit of 0.2, indicating the isolates to be of high antifungal usage origin. The molecularly identified species had 99–100% similarity with reference strains from GenBank and evolutionary relationship of taxa revealed 10 distinct clades. The outcome of this study reveals a rise in the frequency of antifungal resistance in moulds towards standard drugs, thus, advocating for adequate investigations targeted at monitoring antifungal resistance in groundwater milieus.