Candida auris, a multidrug-resistant yeast, poses significant challenges in healthcare settings due to its ability to form biofilms and resistance to common disinfectants. Understanding its susceptibility to biocides used in hospital disinfection practices is crucial for infection control. We investigated the biocide sensitivity of eight clinical C. auris strains from different patients and one reference strain (CDC B11903) using the biocide activity tests. Species identification was confirmed through MALDI-TOF MS, while clade differentiation and phylogenetic classification were determined via whole-genome sequencing. Biofilm formation was assessed using the MTT assay. Antifungal susceptibilities were tested according to CLSI standards. The effectiveness of biocides, including chlorine, chlorhexidine, and benzalkonium chloride, was evaluated through broth microdilution following CLSI standards and quantitative suspension and carrier tests, following EN standards. All clinical strains were identified as clade 1, and the reference strain as clade 4, with all exhibiting biofilm formation. Clade 1 strains showed resistance to fluconazole, with MIC values ranging from 8 to 32 µg/ml, while being susceptible to other antifungals. Broth microdilution MIC assays for biocides demonstrated that all strains exhibited resistance to benzalkonium chloride. Chlorine and chlorhexidine showed variable efficacy, dependent on concentration and environmental cleanliness. Alcohol-based hand sanitizers demonstrated effectiveness against C. auris from the first minute of application. The study highlights the variable susceptibility of C.auris to different biocides, underscoring the challenge in eradicating this pathogen from healthcare environments. Our findings advocate for the careful selection of disinfectants in hospital settings, emphasizing the need for high-concentration chlorine and chlorhexidine solutions to combat C. auris, even in especially clean environments.

Purpose: Cystic echinococcosis (CE) is caused by the larval form of Echinococcus granulosus. Clinical, radiologic, pathologic, and serologic findings should be evaluated together for the diagnosis of CE. The sensitivity and specificity oalf serologic tests may vary depending on the method used. In this study, we aimed to detect IgG antibodies specific to E. granulosus using indirect hemagglutination assay (IHA), enzyme-linked immunosorbent assay (ELISA), indirect fluorescent antibodies (IFA) and western blot (WB) tests. Methods: In our study, the serum samples of 74 patients sent to our laboratory with suspicion of CE were studied using two different commercial IHA tests, ELISA, IFA and WB test. The test results were evaluated along with radiological findings and histopathological examinations, the latter being the gold standard. Results: Of all the patients, 51 (69%) were female and 23 (31%) were male. There was a statistically significant difference between males and females (χ² = 9.7, p = 0.002). Out of 74 patients, positivity rates for Siemens IHA, Fumouze IHA, ELISA, IFA and WB test were positive as 33 (44.6%), 35 (47.3%), 43 (58.1%), 42 (56.7%) and 38 (51.3%), respectively. The sensitivity and specificity of the tests were as follows: 66.67 and 2.31% for Siemens IHA; 70.83% and 96.15% for Fumouze IHA; 85.42%, and 88.46% for ELISA; 83.33% and 88.46% for IFA; 72.92% and 88.46% for WB test. Conclusion: There were statistically significant differences in between all five methods (p < 0,001). While the tests with the highest specificity was Fumouze IHA, the test with the highest sensitivity was the ELISA test. It was concluded that IHA and ELISA tests were more practical in practice because of their greater applicability.

Ralstonia solanacearum is a very rare cause of infection in humans. There is no described nosocomial outbreak due to R. solanacearum until yet. We determined R. solanacearum as the source of catheter-related bloodstream infection (CRBSI) outbreak. This outbreak analysis was carried out in a 1000-bed tertiary care university hospital in Turkey. The outbreak analysis included haematology, oncology, nephrology, gastroenterology wards, emergency department and intensive care units. The first case with R. solanacearum CRBSI was detected on May 20, 2019 and R. solanacearum was isolated in catheter blood cultures in 34 patients until October 3, 2019 Results: Standart outbreak analysis procedures were applied. Culture samples were taken from the fluids administered via catheters. Cultures did not yield any bacteria. As a result of the investigation in storage area, it was found that there were leaks, air bubbles and water drops inside the packaging of saline solutions. R. solanacearum was yielded in the cultures obtained from the surface of saline bags and inner side of plastic packings. To validate our hypothesis, a clonal analysis was performed by Arbitrarily Primed - PCR method and the 16S rRNA gene for identification among isolates. All R. solanacearum isolates were monoclonal and identical. This is the first outbreak of R. solanacearum CRBSI described in hospital settings. The source of the outbreak was a contamination in the surface of saline bag and inner side of plastic packing. Efficacy of an active surveillance system, accurate and rapid conduction of microbiological identification are essential for outbreak management.

Background: Candidozyma auris is an emerging multidrug-resistant fungal pathogen responsible for nosocomial outbreaks worldwide. In addition to antifungal resistance, its ability to persist in the hospital environment and tolerate commonly used biocides presents a critical challenge for infection control. However, the relationship between biocide tolerance, antifungal resistance, and virulence traits in C. auris remains poorly understood. Methods: In this study, 47 C. auris Clade 1 isolates were evaluated using phenotypic and genotypic methods. ITS region sequencing was performed using Oxford Nanopore technology. Susceptibility testing was conducted for seven antifungal agents and four biocides using the CLSI reference microdilution method. Virulence factors including biofilm formation, secreted aspartyl proteinase, esterase, caseinase, phospholipase, and hemolysis were assessed. Results: All isolates were identified as Clade 1. MIC values for antifungals ranged from 0.015 to 64 µg/mL, and for biocides from 0.0078 to 128 mg/L. Fluconazole resistance was found in 31% of isolates, while amphotericin B resistance was 4%; no echinocandin resistance was observed. Biofilm and SAP activity were detected in all isolates; esterase was positive in 87%, and caseinase in 4%. Statistically significant correlations were observed between amphotericin B and isavuconazole MICs (ρ = 0.32, p = 0.028), amphotericin B and triclosan MICs (ρ = 0.35, p = 0.018), and amphotericin B MICs and caseinase activity (ρ = 0.31, p = 0.035). These findings suggest potential phenotypic links between antifungal resistance and specific virulence traits. Conclusions: This is the first study from Türkiye to evaluate the antifungal and biocide susceptibility alongside virulence characteristics of Clade 1 C. auris. While statistically significant associations were observed, we acknowledge that resistance mechanisms and pathogenicity pathways are distinct. Therefore, these correlations should be interpreted cautiously and warrant further investigation at the molecular level.

Kandidemilerde etken tür dağılımında ve antifungal duyarlılık durumundaki değişimler, hastalarda prognozu etkileyebilmektedir. Bu çalışma, COVID-19 pandemisi öncesi (2016-2019) ve sonrası (2020-2024) dönemlerde kan kültürlerinden izole edilen mantar türlerinin dağılımlarını ve antifungal duyarlılıklarını karşılaştırmayı amaçlamaktadır. Çalışmada, Gazi Üniversitesi Tıp Fakültesi Tıbbi Mikrobiyoloji Laboratuvarı'nda 2016-2024 yılları arasında kan kültürlerinden izole edilen mantar türleri değerlendirilmiştir. Kan kültürleri COVID-19 öncesi ve COVID-19 sonrası dönemde BACT/ALERT® 3D cihazında inkübe edilmiştir. Üreyen mantarların tanımlanmasında pandemiden önce fenotipik yöntemler (ID32C) kullanılırken, pandemi sonrası dönemde VITEK® MS (MALDI-TOF MS) sisteminden yararlanılmıştır. Antifungal duyarlılık testleri CLSI M27-A3 mikrodilüsyon referans yöntemiyle yapılmıştır. Gazi Üniversitesi Hastanesi’nde 2016-2019 ve 2020-2024 dönemlerinde alınan toplam 148734 kan kültürünün analizi yapılmıştır. COVID-19 öncesi dönemde pozitif kültür oranı %16 (8397/53835) ve mantar pozitifliği %5 (391/8397) iken, pandemi sonrası dönemde bu oranlar sırasıyla %17 (16.572/94.899) ve %5 (845/16.572) olarak saptanmıştır. En sık izole edilen dört tür her iki dönemde Candida albicans (%40→%39), Nakaseomyces glabratus (%19→%18), Candida parapsilosis (%14→%23) ve Candida tropicalis (%9→%7) olmuş, C. parapsilosis’teki artış istatistiksel olarak anlamlı bulunmuştur (p=0.011). MİK90 değerleri esas alındığında flukonazol için C. tropicalis’te (4→8 µg/ml), vorikonazol için N. glabratus ve C. tropicalis’te (sırasıyla 0.25→2 ve 0.25→4 µg/ml), amfoterisin B için ise C. albicans ve C. parapsilosis’te (0.25→1 µg/ml) artış izlenmiştir. Bu bulgular, bazı türlerde antifungal duyarlılığın azaldığını ve dikkatli izlenmesi gerektiğini göstermektedir. Pandemi öncesi ve sonrası dönemde etken dağılımlarında sınırlı farklılıklar izlenmiş, antifungal direnç açısından dikkat çekici artışlar gözlemlenmiştir. Klinik mikrobiyoloji laboratuvarlarının düzenli aralıklarla tür ve duyarlılık dağılımlarını değerlendirmesi önerilmektedir.

Candida auris is an emerging multidrug‐resistant yeast demonstrating remarkable persistence in healthcare environments, contributing to nosocomial transmission and outbreak persistence. Increasing disinfectant failure reports have raised concerns regarding infection control policies, as environmental reservoirs play central roles in its spread. We reviewed experimental studies, environmental surveillance reports, and comparative disinfection efficacy data to summarise interactions between C. auris and commonly used biocidal classes: chlorine‐based oxidizers, alcohol formulations, biguanides, and quaternary ammonium compounds. Mechanistic findings on biofilm formation, efflux activity, and stress‐response pathways were integrated to contextualise tolerance behaviour. Evidence indicates C. auris shows reduced susceptibility to quaternary ammonium compounds and demonstrates variable, strain‐dependent tolerance to alcohol‐based disinfectants, particularly with organic load or suboptimal contact times. Chlorine‐based oxidising agents maintain reliable activity at appropriate concentrations and exposure durations. Biofilm formation enhances environmental persistence and diminishes surface decontamination efficiency. C. auris requires disinfectant strategies distinct from other Candida species. Effective infection prevention depends on optimised agent selection, adequate contact times, and consideration of surface and organic‐matter conditions. Tailored decontamination protocols are essential to limit environmental persistence and interrupt nosocomial transmission.