Characteristics, Risk Factors, and Survival Analysis of Candida auris Cases: Results of One-Year National Surveillance Data from Oman

Key Factors to Consider for Candida auris Screening in Healthcare Settings: A Systematic Review

BACKGROUND

Candida auris is an emerging fungal pathogen that is often multidrug-resistant. It can persist on skin and in hospital environments, leading to outbreaks and severe infections for patients at risk. Several countries and institutions are working on establishing guidelines and recommendations for prevention. This review aims to assess the evidence on factors associated with C. auris colonisation or infection, the duration of such colonisation, possible colonisation sites, and the risk of secondary cases to inform screening recommendations.

METHODS

We systematically searched five databases for primary studies and systematic reviews of our four outcomes. We excluded studies on treatment, management, laboratory methods, drug resistance, and environmental screening. From each paper, we extracted relevant data and summarised them in tables. Main findings were described narratively.

FINDINGS

We selected 117 studies for inclusion. Most of the studies were observational studies. Without taking the method of testing into account, the duration of C. auris colonisation varied, with up to and beyond a year being common. The predominant sites of colonisation were the axillae and groin, with the nares and rectum being less common sites. The risk of secondary cases saw considerable variation across the studies, and the secondary cases primarily involved patients and not healthcare workers. Critical care settings, invasive medical devices, recent antimicrobial use, and comorbidities were often associated with C. auris colonisation and infection.

CONCLUSION

Our review highlights that, despite relevant findings on factors influencing C. auris colonisation and infection, substantial gaps remain in the evidence supporting screening practices. Most studies were conducted reactively, in outbreak settings, and lack systematic protocols. Given these limitations, screening guidelines are likely to be more successful if grounded in medical theory and yeast microbiology rather than relying solely on current studies. Rigorous, well-designed research is urgently needed to inform future C. auris screening and control efforts.

Investigation and successful control of a Candida auris outbreak at a tertiary health care facility in Kenya

Objectives

This study aimed to conduct an epidemiological and genomic investigation of a hospital outbreak of Candida auris, and implement measures for its control.

Methods

We collected demographic and clinical data from medical records of patients with C. auris from January 2017 to June 2019 after identifying increased cases in April 2019. Point-prevalence surveys for C. auris colonisation were conducted in the critical care units (CCU). Antifungal susceptibility testing and genomic sequencing of isolates were performed. A bundle of infection prevention and control measures was instituted.

Results

Thirty-two patients with C. auris were identified. All patients had a history of CCU admission. A total of 283 screening swabs were obtained and 57 isolates of C. auris identified. Antifungal susceptibility testing was performed on 48 isolates. All but two isolates were resistant to fluconazole; one isolate was also resistant to amphotericin B. Forty-one of 46 isolate genomes were clonally related and formed a distinct genetic cluster in Clade III. C. auris colonisation reduced from 42% in June 2019 to 1% in August 2019, and no new hospital-acquired colonisation was identified in the subsequent 9 months.

Conclusions

We identified a new genetic subcluster of Clade III C. auris. We also show that strict implementation of infection prevention measures can lead to substantial reductions in C. auris transmission.

Application of Raman spectroscopy and machine learning for Candida auris identification and characterization

Candida auris, an emerging fungal pathogen characterized by multidrug resistance and high-mortality nosocomial infections, poses a serious global health threat. However, the precise and rapid identification and characterization of C. auris remain a challenge. Here, we employed Raman spectroscopy combined with machine learning to identify C. auris isolates and its closely related species as well as to predict antifungal resistance and key virulence factors at the single-cell level. The average accuracy of identification among all Candida species was 93.33%, with an accuracy of 98% for the clinically simulated samples. The drug susceptibility of C. auris to fluconazole and amphotericin B was 99% and 94%, respectively. Furthermore, the phenotypic prediction of C. auris yielded an accuracy of 100% for aggregating cells and 97% for filamentous cells. This proof-of-concept methodology not only precisely identifies C. auris at the clade-specific level but also rapidly predicts the antifungal resistance and biological characteristics, promising a valuable medical diagnostic tool to combat this multidrug-resistant pathogen in the future.

IMPORTANCE

Currently, combating Candida auris infections and transmission is challenging due to the lack of efficient identification and characterization methods for this species. To address these challenges, our study presents a novel approach that utilizes Raman spectroscopy and artificial intelligence to achieve precise identification and characterization of C. auris at the singe-cell level. It can accurately identify a single cell from the four C. auris clades. Additionally, we developed machine learning models designed to detect antifungal resistance in C. auris cells and differentiate between two distinct phenotypes based on the single-cell Raman spectrum. We also constructed prediction models for detecting aggregating and filamentous cells in C. auris, both of which are closely linked to its virulence. These results underscore the merits of Raman spectroscopy in the identification and characterization of C. auris, promising improved outcomes in the battle against C. auris infections and transmission.

Uniqueness of Candida auris cell wall in morphogenesis, virulence, resistance, and immune evasion

Candida auris has drawn global attention due to its alarming multidrug resistance and the emergence of pan resistant strains. C. auris poses a significant risk in nosocomial candidemia especially among immunocompromised patients. C. auris showed unique virulence characteristics associated with cell wall including cell polymorphism, adaptation, endurance on inanimate surfaces, tolerance to external conditions, and immune evasion. Notably, it possesses a distinctive cell wall composition, with an outer mannan layer shielding the inner 1,3-β glucan from immune recognition, thereby enabling immune evasion and drug resistance. This review aimed to comprehend the association between unique characteristics of C. auris's cell wall and virulence, resistance mechanisms, and immune evasion. This is particularly relevant since the fungal cell wall has no human homology, providing a potential therapeutic target. Understanding the complex interactions between the cell wall and the host immune system is essential for devising effective treatment strategies, such as the use of repurposed medications, novel therapeutic agents, and immunotherapy like monoclonal antibodies. This therapeutic targeting strategy of C. auris holds promise for effective eradication of this resilient pathogen.

Prevalence and Outcomes of Candida auris Infections in a Tertiary Hospital in the United Arab Emirates (UAE)

Background Candida auris (C. auris) is an emerging serious threat to healthcare settings, with an average mortality of 45% in cases of bloodstream infections. This study aimed to determine the prevalence of C. auris in a single center in the UAE during the year 2022 and understand risk factors related to poor outcomes. Methods This retrospective cohort chart review at Al-Qassimi Hospital encompassed all confirmed Candida infections, including C. auris, from January to December 2022. The study involved male and female patients aged 13 years and older, using comprehensive data extracted from the hospital's electronic healthcare records. The analysis included clinical, laboratory, and epidemiological data. Adhering to the 2011 Declaration of Helsinki and Good Pharmacoepidemiology Practices, the study received Institutional Review Board approval, with informed consent waived due to its retrospective design. Data were summarized using appropriate statistical methods, including the unpaired t-test, Mann-Whitney U test, Chi-square test, and Fisher exact test. A significance level of 95% (p<0.05) was maintained throughout the statistical analyses. Results Of the 75 confirmed Candidainfections, 53 (70.7%) were C. auris-positive cases. About 23 (43.4%) of the C. auris group were above 65 years old. Most cases of C. auris group were hospital-acquired (49, 92.5%). The highest number of positive cases were found in urine samples. The demographic and clinical profiles of the C. auris and non-auris groups candidemia were largely similar, except for differences in antifungal use history and ICU requirements. Notably, the C. auris group had a significantly lower history of antifungal use and a lower ICU requirement compared to the non-auris group. The study also highlighted the higher mortality rate associated with candidemia. While mortality was higher in the non-auris group, the difference was not statistically significant. Conclusions The findings of the study suggest that while C. auris poses a serious threat, particularly in hospital settings; the clinical and demographic factors influencing its spread and impact are complex and warrant further investigation. Understanding these factors is crucial for developing effective strategies to prevent and manage C. auris infections, particularly in vulnerable patient populations.

Antifungal efficacy of natural antiseptic products against Candida auris

Candida auris is an emerging fungal pathogen responsible for healthcare-associated infections and outbreaks with high mortality around the world. It readily colonizes the skin, nares, respiratory and urinary tract of hospitalized patients, and such colonization may lead to invasive Candida infection in susceptible patients. However, there is no recommended decolonization protocol for C. auris by international health authorities. The aim of this study is to evaluate the susceptibility of C. auris to commonly used synthetic and natural antiseptic products using an in vitro, broth microdilution assay. Synthetic antiseptics including chlorhexidine, povidone-iodine, and nystatin were shown to be fungicidal against C. auris. Among the natural antiseptics tested, tea tree oil and manuka oil were both fungicidal against C. auris at concentrations less than or equal to 1.25% (v/v). Manuka honey inhibited C. auris at 25% (v/v) concentrations. Among the commercial products tested, manuka body wash and mouthwash were fungicidal against C. auris at concentrations less than or equal to 0.39% (w/v) and 6.25% (v/v) of products as supplied for use, respectively, while tea tree body wash and MedihoneyTM wound gel demonstrated fungistatic properties. In conclusion, this study demonstrated good in vitro antifungal efficacy of tea tree oil, manuka oil, manuka honey, and commercially available antiseptic products containing these active ingredients. Future studies are warranted to evaluate the effectiveness of these antiseptic products in clinical settings.

Candida auris-a systematic review to inform the world health organization fungal priority pathogens list

The World Health Organization (WHO) in 2022 developed a fungal priority pathogen list. Candida auris was ultimately ranked as a critical priority pathogen. PubMed and Web of Science were used to find studies published from 1 January 2011 to 18 February 2021, reporting on predefined criteria including: mortality, morbidity (i.e., hospitalization and disability), drug resistance, preventability, yearly incidence, and distribution/emergence. Thirty-seven studies were included in the final analysis. The overall and 30-day mortality rates associated with C. auris candidaemia ranged from 29% to 62% and 23% to 67%, respectively. The median length of hospital stay was 46-68 days, ranging up to 140 days. Late-onset complications of C. auris candidaemia included metastatic septic complications. Resistance rates to fluconazole were as high as 87%-100%. Susceptibility to isavuconazole, itraconazole, and posaconazole varied with MIC90 values of 0.06-1.0 mg/l. Resistance rates to voriconazole ranged widely from 28% to 98%. Resistance rates ranged between 8% and 35% for amphotericin B and 0%-8% for echinocandins. Over the last ten years, outbreaks due to C. auris have been reported in in all WHO regions. Given the outbreak potential of C. auris, the emergence and spread of MDR strains, and the challenges associated with its identification, and eradication of its environmental sources in healthcare settings, prevention and control measures based on the identified risk factors should be evaluated for their effectiveness and feasibility. Global surveillance studies could better inform the incidence rates and distribution patterns to evaluate the global burden of C. auris infections.

Candida auris in Greek healthcare facilities: Active surveillance results on first cases and outbreaks from eleven hospitals within Attica region

BACKGROUND

Candida auris was sporadically detected in Greece until 2019. Thereupon, there has been an increase in isolations among inpatients of healthcare facilities.

AIM

We aim to report active surveillance data on MALDI-TOF confirmed Candida auris cases and outbreaks, from November 2019 to September 2021.

METHODS

A retrospective study on hospital-based Candida auris data, over a 23-month period was conducted, involving 11 hospitals within Attica region. Antifungal susceptibility testing and genotyping were conducted. Case mortality and fatality rates were calculated and p-values less than 0.05 were considered statistically significant. Infection control measures were enforced and enhanced.

RESULTS

Twenty cases with invasive infection and 25 colonized were identified (median age: 72 years), all admitted to hospitals for reasons other than fungal infections. Median hospitalisation time until diagnosis was 26 days. Common risk factors among cases were the presence of indwelling devices (91.1 %), concurrent bacterial infections during hospitalisation (60.0 %), multiple antimicrobial drug treatment courses prior to hospitalisation (57.8 %), and admission in the ICU (44.4 %). Overall mortality rate was 53 %, after a median of 41.5 hospitalisation days. Resistance to fluconazole and amphotericin B was identified in 100 % and 3 % of tested clinical isolates, respectively. All isolates belonged to South Asian clade I. Outbreaks were identified in six hospitals, while remaining hospitals detected sporadic C. auris cases.

CONCLUSION

Candida auris has proven its ability to rapidly spread and persist among inpatients and environment of healthcare facilities. Surveillance focused on the presence of risk factors and local epidemiology, and implementation of strict infection control measures remain the most useful interventions.

The laboratory investigation, management, and infection prevention and control of Candida auris: a narrative review to inform the 2024 national guidance update in England

The emergent fungal pathogen Candida auris is increasingly recognised as an important cause of healthcare-associated infections globally. It is highly transmissible, adaptable, and persistent, resulting in an organism with significant outbreak potential that risks devastating consequences. Progress in the ability to identify C. auris in clinical specimens is encouraging, but laboratory diagnostic capacity and surveillance systems are lacking in many countries. Intrinsic resistance to commonly used antifungals, combined with the ability to rapidly acquire resistance to therapy, substantially restricts treatment options and novel agents are desperately needed. Despite this, outbreaks can be interrupted, and mortality avoided or minimised, through the application of rigorous infection prevention and control measures with an increasing evidence base. This review provides an update on epidemiology, the impact of the COVID-19 pandemic, risk factors, identification and typing, resistance profiles, treatment, detection of colonisation, and infection prevention and control measures for C. auris. This review has informed a planned 2024 update to the United Kingdom Health Security Agency (UKHSA) guidance on the laboratory investigation, management, and infection prevention and control of Candida auris. A multidisciplinary response is needed to control C. auris transmission in a healthcare setting and should emphasise outbreak preparedness and response, rapid contact tracing and isolation or cohorting of patients and staff, strict hand hygiene and other infection prevention and control measures, dedicated or single-use equipment, appropriate disinfection, and effective communication concerning patient transfers and discharge.

The Gordian Knot of C. auris: If You Cannot Cut It, Prevent It

Since its first description in 2009, Candida auris has, so far, resulted in large hospital outbreaks worldwide and is considered an emerging global public health threat. Exceptionally for yeast, it is gifted with a profoundly worrying invasive potential and high inter-patient transmissibility. At the same time, it is capable of colonizing and persisting in both patients and hospital settings for prolonged periods of time, thus creating a vicious cycle of acquisition, spreading, and infection. It exhibits various virulence qualities and thermotolerance, osmotolerance, filamentation, biofilm formation and hydrolytic enzyme production, which are mainly implicated in its pathogenesis. Owing to its unfavorable profile of resistance to diverse antifungal agents and the lack of effective treatment options, the implementation of robust infection prevention and control (IPC) practices is crucial for controlling and minimizing intra-hospital transmission of C. auris. Rapid and accurate microbiological identification, adherence to hand hygiene, use of adequate personal protective equipment (PPE), proper handling of catheters and implantable devices, contact isolation, periodical environmental decontamination, targeted screening, implementation of antimicrobial stewardship (AMS) programs and communication between healthcare facilities about residents' C. auris colonization status are recognized as coherent strategies for preventing its spread. Current knowledge on C. auris epidemiology, clinical characteristics, and its mechanisms of pathogenicity are summarized in the present review and a comprehensive overview of IPC practices ensuring yeast prevention is also provided.

Description of Candida auris Occurrence in a Tertiary Health Institution in Riyadh, Saudi Arabia

BACKGROUND

Candida auris is an emerging multidrug-resistant fungal pathogen that represents a current serious threat to healthcare settings.

OBJECTIVE

The objective was to determine the prevalence of C. auris in a Riyadh hospital since its initial detection in late 2019.

METHODS

Using an adapted risk assessment tool, we reviewed the charts and medical files of all suspected and confirmed cases of C. auris infections reported at King Khalid University Hospital, Riyadh, between November 2019 and December 2022. Anonymized data were retrieved in a pre-established datasheet and analyzed to determine the epidemiological characteristics of C. auris infections in our facility. We analyzed prevalence by age, gender, risk factors, and according to sampling source.

RESULTS

Of the 53 confirmed C. auris-positive cases during the study period, 33 (62%) were males. Their ages ranged between 15 and 98, with most positive cases occurring in those aged 50 and above. Only one of the confirmed cases was hospital-acquired. All patients had at least one risk factor, and urine samples yielded the greatest number of positive cases, while admission to healthcare facilities constituted the highest risk in our study.

CONCLUSION

Establishing a local prevalence pattern could serve as a baseline/benchmark to compare with regional and international benchmarks.

Candida auris from colonisation to candidemia: A four-year study

BACKGROUND

Candida auris has become a worrisome multi-drug resistant healthcare-associated pathogen due to its capacity to colonise patients and surfaces and to cause outbreaks of invasive infections in critically ill patients.

OBJECTIVES

This study evaluated the outbreak in our setting in a 4-year period, reporting the risk factors for developing candidemia in previously colonised patients, the therapeutic measures for candidemia and the outcome of candidemia and colonisation cases among all C. auris isolates and their susceptibility to antifungals.

METHODS

Data were retrospectively collected from patients admitted to Consorcio Hospital General Universitario de Valencia (Spain) from September 2017 to September 2021. A retrospective case-control study was designed to identify risk factors for developing C. auris candidemia in previously colonised patients.

RESULTS

C. auris affected 550 patients, of which 210 (38.2%) had some clinical sample positive. Isolates were uniformly resistant to fluconazole, 20 isolates were resistant to echinocandins (2.8%) and four isolates were resistant to ampfotericin B (0.6%). There were 86 candidemia cases. APACHE II, digestive disease and catheter isolate were proven to be independent risk factors for developing candidemia in previously colonised patients. Thirty-day mortality rate for C. auris candidemia cases was 32.6%, while for colonisation cases was 33.7%.

CONCLUSIONS

Candidemia was one of the most frequent and severe infections caused by C. auris. The risk factors identified in this study should help to detect patients who are at more risk of developing candidemia, as long as an adequate surveillance of C. auris colonisation is performed.

Candida auris in Intensive Care Setting: The First Case Reported in Portugal

Candida auris is an opportunistic human pathogen that has rapidly spread to multiple countries and continents and has been associated with a high number of nosocomial outbreaks. Herein, we report the first case of C. auris in Portugal, which was associated with a patient transferred from Angola to an ICU in Portugal for liver transplantation after a SARS-CoV-2 infection. C. auris was isolated during the course of bronchoalveolar lavage, and it was subjected to antifungal susceptibility testing and whole-genome sequence analysis. This isolate presents low susceptibility to azoles and belongs to the genetic clade III with a phylogenetic placement close to African isolates. Although clade III has already been reported in Europe, taking into account the patient's clinical history, we cannot discard the possibility that the patient's colonization/infection occurred in Angola, prior to admission in the Portuguese hospital. Considering that C. auris is a fungal pathogen referenced by WHO as a critical priority, this case reinforces the need for continuous surveillance in a hospital setting.

Candida auris Blood stream infection- a descriptive study from Qatar

BACKGROUND

Candida auris is an emerging yeast pathogen that can cause invasive infections, particularly candidemia, in healthcare settings. Candida auris is characterized by resistance to multiple classes of antifungal drugs and high mortality.

OBJECTIVE

To describe the risk factors, clinical characteristics, antifungal susceptibility pattern and outcomes of Candida auris blood stream infection.

METHODS

We conducted a retrospective review of electronic medical records of C. auris fungemia cases in the facilities under Hamad Medical corporation, Qatar from 1/11/2018 to 31/7/2021. Demographic data, risk factors, antibiogram and 30-day outcome are described.

RESULTS

We identified 36 patients with C. auris fungemia. Most of the patients were in intensive care unit following severe COVID-19 pneumonia and had received steroids and broad-spectrum antibiotics. Most cases were central line related. Over 90% of isolates were non-susceptible to fluconazole, while amphotericin B resistance reached 85%. Factors associated with high mortality included initial SOFA score of 9 or above and absence of source control.

CONCLUSION

Our study reveals a concerning 41.6% mortality rate within 30 days of C. auris candidemia. Furthermore, the prevalence of amphotericin B resistance in Qatar exceeds what has been reported in the literature necessitating further exploration. Echinocandins retains nearly 100% susceptibility and should be prioritized as the treatment of choice. These findings emphasize the need for vigilant monitoring and appropriate management strategies to combat C. auris infections and improve patient outcomes.

Cellular apoptosis and cell cycle arrest as potential therapeutic targets for eugenol derivatives in Candida auris

Candida auris, the youngest Candida species, is known to cause candidiasis and candidemia in humans and has been related to several hospital outbreaks. Moreover, Candida auris infections are largely resistant to the antifungal drugs currently in clinical use, necessitating the development of novel medications and approaches to treat such infections. Following up on our previous studies that demonstrated eugenol tosylate congeners (ETCs) to have antifungal activity, several ETCs (C1-C6) were synthesized to find a lead molecule with the requisite antifungal activity against C. auris. Preliminary tests, including broth microdilution and the MUSE cell viability assay, identified C5 as the most active derivative, with a MIC value of 0.98 g/mL against all strains tested. Cell count and viability assays further validated the fungicidal activity of C5. Apoptotic indicators, such as phosphatidylserine externalization, DNA fragmentation, mitochondrial depolarization, decreased cytochrome c and oxidase activity and cell death confirmed that C5 caused apoptosis in C. auris isolates. The low cytotoxicity of C5 further confirmed the safety of using this derivative in future studies. To support the conclusions drawn in this investigation, additional in vivo experiments demonstrating the antifungal activity of this lead compound in animal models will be needed.

The Mortality Attributable to Candidemia in C. auris Is Higher than That in Other Candida Species: Myth or Reality?

Candida auris has become a major health threat due to its transmissibility, multidrug resistance and severe outcomes. In a case-control design, 74 hospitalised patients with candidemia were enrolled. In total, 22 cases (29.7%) and 52 controls (C. albicans, 21.6%; C. parapsilosis, 21.6%; C. tropicalis, 21.6%; C. glabrata, 1.4%) were included and analysed in this study. Risk factors, clinical and microbiological characteristics and outcomes of patients with C. auris and non-auris Candida species (NACS) candidemia were compared. Previous fluconazole exposure was significantly higher in C. auris candidemia patients (OR 3.3; 1.15–9.5). Most C. auris isolates were resistant to fluconazole (86.3%) and amphotericin B (59%) whilst NACS isolates were generally susceptible. No isolates resistant to echinocandins were detected. The average time to start antifungal therapy was 3.6 days. Sixty-three (85.1%) patients received adequate antifungal therapy, without significant differences between the two groups. The crude mortality at 30 and 90 days of candidemia was up to 37.8% and 40.5%, respectively. However, there was no difference in mortality both at 30 and 90 days between the group with candidemia by C. auris (31.8%) and by NACS (42.3%) (OR 0.6; 95% IC 0.24–1.97) and 36.4% and 42.3% (0.77; 0.27–2.1), respectively. In this study, mortality due to candidemia between C. auris and NACS was similar. Appropriate antifungal therapy in both groups may have contributed to finding no differences in outcomes.

Usefulness of screening for Candida auris colonisation in international patients admitted to a large university hospital

INTRODUCTION

Candida auris is an emerging pathogen in health care-associated infections. In contrast to many other countries with rising numbers of C. auris, only seven cases have been reported in Germany from 2015 to 2017, mostly from patients who received prior medical treatment abroad. We therefore established a mandatory screening for C. auris colonisation at our tertiary care centre for all patients who were admitted as international patients or previously hospitalised in a foreign country within the past 6 months.

METHODS

Colonisation of patients was assessed using a previously established screening protocol for multidrug resistant bacteria. Since 2017, all screening samples were additionally analysed for C. auris using CHROMagar Candida (CHROMagar, Paris, France). Yeast isolates were identified using matrix-assisted laser ionisation time-of-flight (MALDI TOF), except for C. albicans (identified by the typical green colour on chromogenic agar). Data were analysed retrospectively.

RESULTS

Our study cohort included 655 patients and an overall number of 1399 samples. Fifty-three patients were colonised with Candida species (C. albicans, n = 37; C. glabrata, n = 14; others n = 9). No case of C. auris was detected. Candida spp. were mainly detected from respiratory samples (5.4% positive) and gastrointestinal specimen (5.2%). Laboratory costs were 14,689 € and analyses resulted in 98.7 h of additional technician's work.

CONCLUSION

No colonisation with C. auris was detected among patients with previous hospitalisation abroad. Universal C. auris screening of patients with any contact to foreign health care does not seem to be cost-effective in our setting and more targeted screening strategies have to be developed.

Functional Expression of Recombinant Candida auris Proteins in Saccharomyces cerevisiae Enables Azole Susceptibility Evaluation and Drug Discovery

Candida auris infections are difficult to treat due to acquired drug resistance against one or multiple antifungal drug classes. The most prominent resistance mechanisms in C. auris are overexpression and point mutations in Erg11, and the overexpression of efflux pump genes CDR1 and MDR1. We report the establishment of a novel platform for molecular analysis and drug screening based on acquired azole-resistance mechanisms found in C. auris. Constitutive functional overexpression of wild-type C. auris Erg11, Erg11 with amino acid substitutions Y132F or K143R and the recombinant efflux pumps Cdr1 and Mdr1 has been achieved in Saccharomyces cerevisiae. Phenotypes were evaluated for standard azoles and the tetrazole VT-1161. Overexpression of CauErg11 Y132F, CauErg11 K143R, and CauMdr1 conferred resistance exclusively to the short-tailed azoles Fluconazole and Voriconazole. Strains overexpressing the Cdr1 protein were pan-azole resistant. While CauErg11 Y132F increased VT-1161 resistance, K143R had no impact. Type II binding spectra showed tight azole binding to the affinity-purified recombinant CauErg11 protein. The Nile Red assay confirmed the efflux functions of CauMdr1 and CauCdr1, which were specifically inhibited by MCC1189 and Beauvericin, respectively. CauCdr1 exhibited ATPase activity that was inhibited by Oligomycin. The S. cerevisiae overexpression platform enables evaluation of the interaction of existing and novel azole drugs with their primary target CauErg11 and their susceptibility to drug efflux.

Global Prevalence and Subgroup Analyses of Coronavirus Disease (COVID-19) Associated Candida auris infections (CACa): A Systematic Review and Meta-Analysis

Background

Increased hospitalisation rates in the Coronavirus disease 19 (COVID‐19) era lead to a new wave of hospital‐acquired infections such as emerging multidrug‐resistant Candida auris. We aimed to evaluate and estimate the global prevalence of coronavirus‐associated C. auris infection (CACa).

Methods

We searched related databases between December 2019 and April 2022 for studies that reported data about CACa. Meta‐analysis was performed using MedCalc software version 20.104 according to the DerSimonian and Laird method applying the random‐effects model. We evaluated heterogeneity using the χ²‐based Q statistic (significant for p‐value < .1) and the I² statistic (>75% indicative of ‘notable’ heterogeneity). Moreover, if possible, an odds ratio (OR) analysis was performed for eligible data.

Results

Our meta‐analysis includes ten eligible studies, including 1942 patients hospitalised with COVID‐19; 129 were C. auris cases. The overall pooled prevalence of CACa was estimated at 5.7%. The mortality rate of CACa was estimated at 67.849%. Hypertension was the most prevalent comorbidity (59.374%), followed by diabetes mellitus (52.898%) and cardiovascular diseases (31.392%). Men with a prevalence rate of 80.012% were 3.27 (OR) times more prone to getting infected by C. auris.

Conclusion

We concluded that the prevalence of C. auris infections decreased during the COVID‐19 pandemic and the prevalence gradient changed from Asia to America. Unfortunately, there are many descriptive studies with duplicate content in the field of epidemiology of C. auris infections which are increasing every day. We suggest further non‐descriptive studies to accurately establish the cause‐and‐effect relationships between C. auris and COVID‐19 infections.

COVID-19 and C. auris: A Case-Control Study from a Tertiary Care Center in Lebanon

Many healthcare centers around the world have reported the surge of Candida auris (C. auris) outbreaks during the COVID-19 pandemic, especially among intensive care unit (ICU) patients. This is a retrospective study conducted at the American University of Beirut Medical Center (AUBMC) between 1 October 2020 and 15 June 2021, to identify risk factors for acquiring C. auris in patients with severe COVID-19 infection and to evaluate the impact of C. auris on mortality in patients admitted to the ICU during that period. Twenty-four non-COVID-19 (COV−) patients were admitted to ICUs at AUBMC during that period and acquired C. auris (C. auris+/COV−). Thirty-two patients admitted with severe COVID-19 (COV+) acquired C. auris (C. auris+/COV+), and 130 patients had severe COVID-19 without C. auris (C. auris−/COV+). Bivariable analysis between the groups of (C. auris+/COV+) and (C. auris−/COV+) showed that higher quick sequential organ failure assessment (qSOFA) score (p < 0.001), prolonged length of stay (LOS) (p = 0.02), and the presence of a urinary catheter (p = 0.015) or of a central venous catheter (CVC) (p = 0.01) were associated with positive culture for C. auris in patients with severe COVID-19. The multivariable analysis showed that prolonged LOS (p = 0.008) and a high qSOFA score (p < 0.001) were the only risk factors independently associated with positive culture for C. auris. Increased LOS (p = 0.02), high “Candida score” (p = 0.01), and septic shock (p < 0.001) were associated with increased mortality within 30 days of positive culture for C. auris. Antifungal therapy for at least 7 days (p = 0.03) appeared to decrease mortality within 30 days of positive culture for C. auris. Only septic shock was associated with increased mortality in patients with C. auris (p = 0.006) in the multivariable analysis. C. auris is an emerging pathogen that constitutes a threat to the healthcare sector.

Prevalence, Risk Factors, Treatment and Outcome of multidrug resistance Candida auris Infections in Coronavirus Disease (COVID-19) Patients: A Systematic Review

BACKGROUND

Candida auris is an emerging multidrug-resistant pathogen in intensive care settings (ICU). During the coronavirus disease 19 (COVID-19) pandemic, ICU admissions were overwhelmed, possibly contributing to the C. auris outbreak in COVID-19 patients.

OBJECTIVES

The present systematic review addresses the prevalence, underlying diseases, iatrogenic risk factors, treatment and outcome of C. auris infections in COVID-19 patients.

METHODS

MEDLINE, Scopus, Embase, Web of Science and LitCovid databases were systematically searched with appropriate keywords from 1^st January 2020 to 31^st December 2021.

RESULTS

A total of 97 cases of C. auris were identified in COVID-19 patients. The prevalence of C. auris infections in COVID-19 patients was 14%. The major underlying diseases were diabetes mellitus (42.7%), hypertension (32.9%), and obesity (14.6%), followed by the iatrogenic risk factors such as a central venous catheter (76.8%%) intensive care unit (ICU) stay (75.6%), and broad-spectrum antibiotic usage (74.3%). There were no significant differences in underlying disease and iatrogenic risk factors among C. auris non-candidemia/colonisation and C. auris candidemia cases. The mortality rate of the total cohort is 44.4%, whereas, in C. auris candidemia patients, the mortality was 64.7%.

CONCLUSION

This study shows that the prevalence of C. auris infections remains unchanged in the COVID-19 pandemic. Hospital-acquired risk factors may contribute to the clinical illness. Proper infection control practices and hospital surveillance may stop future hospital outbreaks during the pandemic.

Expert recommendations for prevention and management of Candida auris transmission

Candida auris was first described as a yeast pathogen in 2009. Since then, the new species has emerged worldwide. In contrast to most other Candida spp., C. auris frequently exhibits multi-drug resistance and is readily transmitted in hospital settings. While most isolations so far are from colonized patients, C. auris does cause life-threatening invasive infections. During management of the first documented C. auris transmission in a German hospital, experts from the National Reference Centers for Invasive Fungal Infections (NRZMyk) and the National Reference Center for Surveillance of Nosocomial Infections screened available literature and integrated available knowledge on infection prevention and C. auris epidemiology and biology to enable optimal containment. Relevant recommendations developed during this process are summarized in this guidance document, intended to assist in management of C. auris transmission and potential outbreak situations. Rapid and effective measures to contain C. auris spread require a multidisciplinary approach that includes clinical specialists of the affected unit, nursing staff, hospital hygiene, diagnostic microbiology, cleaning staff, hospital management and experts in diagnostic mycology / fungal infections. Action should be initiated in a step-wise process and relevant interventions differ between management of singular C. auris colonized / infected patients and detection of potential C. auris transmission or nosocomial outbreaks. [word count 205].

Ninhydrin as a novel DNA hybridization indicator applied to a highly reusable electrochemical genosensor for Candida auris

This work reports a simple strategy for Candida auris genomic DNA (gDNA) detection, a multi-resistant fungus associated with nosocomial outbreaks in healthcare settings, presenting high mortality and morbidity rates. The platform was developed using gold electrode sensitized with specific DNA capture probe and ninhydrin as a novel DNA hybridization indicator. The genosensor was able to detect C. auris in urine sample by differential pulse voltammetry and electrochemical impedance spectroscopy. The biosensor's analytical performance was evaluated by differential pulse voltammetry, detecting up to 4.5 pg μL^-1 of C. auris gDNA in urine (1:10, V/V). Moreover, the genosensor was reused eight times with no loss in the current signal response. The genosensor showed selectivity and stability, maintaining 100% of its response up to 80 days of storage. In order to analyze interactions of single and double-stranded DNA with ninhydrin, SEM, AFM and molecular dynamics studies followed by docking simulations were performed. Theoretical calculations showed ninhydrin interactions more favorably with dsDNA in an A-T rich binding pocket rather than with the ssDNA. Therefore, the proposed system is a promising electrochemical detection device towards a more accurate detection of C. auris gDNA in biological samples.

Metagenomic Sequencing for Direct Identification of Candida auris Colonization

Candida auris is an emerging multidrug-resistant yeast that is associated with skin colonization and deadly bloodstream infections, especially in ventilator skilled nursing facilities. An ongoing question is how this organism colonizes the skin of these patients and whether the skin microbiome provides a measure of colonization resistance against C. auris. Now, Huang et al. (X. Huang, R. M. Welsh, C. Deming, D. M. Proctor, et al., mSphere 6:e00287-21, 2021, https://doi.org/10.1128/mSphere.00287-21) demonstrate a method for shotgun metagenomic analysis of the skin to generate a profile of fungal colonization that is highly correlative with culture-based methods. These methods are likely to assist in the diagnosis of C. auris and the identification of microbiome-associated risk factors that predict invasive disease.