Antifungal Resistance Research Articles

Comprehensive Review of Tinea Capitis in Adults: Epidemiology, Risk Factors, Clinical Presentations, and Management.

Tinea capitis is a fungal infection of the scalp and hair caused by dermatophyte molds, that most often affects children and may also affect adults. Previous estimates suggest that between 3% and 11% of all tinea capitis cases worldwide occur in adults, although updated epidemiological studies are needed to reassess the prevalence of tinea capitis in adult populations specifically. Postmenopausal adult women are most often affected by tinea capitis, with African American or Black women particularly at risk. Adults who experience crowded living conditions, who live in close proximity to animals, who are immunosuppressed, and/or who live in households with affected children are at greatest risk of infection. Tinea capitis can be non-inflammatory or inflammatory in nature, and the subtype affects the extent and severity of clinical symptoms. Fungal culture and potassium hydroxide preparations are the most commonly used diagnostic tools. Trichoscopy, defined as dermoscopic imaging of the scalp and hair, is a useful adjunct to the physical examination. The mainstay of therapy is oral antifungal therapy, and topical therapy alone is not recommended. Since tinea capitis infection is uncommon in adults, there are no widely accepted treatment guidelines. Rather, the same medications used for tinea capitis infection among children are recommended for adults at varying doses, including griseofulvin, and terbinafine, and, less commonly, itraconazole and fluconazole. The prognosis for tinea capitis in adults is typically excellent when prompt and adequate treatment is administered; however, delayed diagnosis or inadequate treatment can result in scarring alopecia. Over the past decade, dermatophyte infections resistant to treatment with topical and oral antifungal agents have emerged. While tinea capitis infections resistant to antifungal therapy have been rarely reported to date, antifungal resistance is rising among superficial fungal infections in general, and antifungal stewardship is necessary to ensure that resistance to treatment does not develop among dermatophytes that cause tinea capitis.

AntiMicro.ai: An Artificial Intelligence powered web application for predicting antibacterial/antifungal susceptibility and constructing personalized machine learning models

Background To train and develop machine learning models on the Pfizer antibacterial and antifungal datasets with subsequent deployment to an interactive Web Application. Methods We utilized R version 4.3.1 to perform descriptive analysis to obtain features/predictors. Python 3.10 libraries NumPy, Pandas, Scikit learn, Pycaret were used to train machine learning models. All these models were scored using area under the curve, recall, precision, F1, Kappa and the Mathews correlation coefficient. The best performing model was then deployed into a web application built on Streamlit after which deployment was done using GitHub and Streamlit cloud. A prototype android app was also developed using GoNative. Results The exploratory data analysis, S Aureus (17.2%) was the most common species however in the sub group analysis of the isolates with genotypic values, K Pneumoniae(48.2%) and E Coli (36.9%) were dominant. Amongst the fungi, Candida albicans (38.3%) and Candida glabrata (15.5%) were dominant. Feature selection was done using Shapley additive explanation plots. Using Extreme Gradient Boosting (XGBoost), we were able to achieve 99% and 97.8% AUC in the prediction of antibacterial and antifungal susceptibility respectively with minimal overfitting. Conclusions Decision tree based methods are a viable options of predicting antibacterial and antifungal drug resistance. When presented in visually appealing modes like web applications and android apps, it can be a useful guide to clinicians on initial treatment while awaiting definitive phenotypic testing. It can also be a surveillance tool that can craft antimicrobial resistance strategies.

Antifungal activity of β-lapachone against a fluconazole-resistant Candida auris strain.

Candida spp. can be found in the human microbiome. However, immunocompromised patients are likely to develop invasive Candida infections, with mortality rates higher than 50%. The discovery of C. auris, a species that rapidly acquire antifungal resistance, increased the concern about Candida infections. The limited number of antifungal agents and the high incidence of resistance to them make imperative the development of new antifungal drugs. β-lapachone is a biological active naphthoquinone that displays antifungal activity against C. albicans and C. glabrata. The aim of this study was to evaluate if this substance affects C. auris growth and elucidate its mechanism of action. A fluconazole-resistant C. auris isolate was used in this study. The antifungal activity of β-lapachone was determined through microbroth dilution assays, and its mechanism of action was evaluated using fluorescent probes. Interaction with fluconazole and amphotericin B was assessed by disk diffusion assay and checkerboard. β-lapachone inhibited planktonic C. auris cell growth by 92.7%, biofilm formation by 84.9%, and decrease the metabolism of preformed biofilms by 87.1% at 100µg/ml. At 100µg/ml, reductions of 30% and 59% of Calcofluor White and Nile red fluorescences were observed, indicating that β-lapachone affects cell wall chitin and neutral lipids content, respectively. Also, the ratio 590nm/529nm of JC-1 decreased 52%, showing that the compound affects mitochondria. No synergism was observed between β-lapachone and fluconazole or amphotericin B. Data show that β-lapachone may be a promising candidate to be used as monotherapy to treat C. auris resistant infections.

Single-repeat MYB transcription factor, OsMYB1R, enhanced phytoalexin sakuranetin accumulation and Magnaporthe oryzae resistance

Sakuranetin, a flavonoid phytoalexin in rice, plays a crucial role in defense against pathogen infection. While MYB-type transcription factors are well-known to regulate plant growth, development, secondary metabolism, and adaptation to environmental stresses, the function of rice MYB-related transcription factors in sakuranetin biosynthesis and sakuranetin-mediated defense remains unclear. In this study, we identified and characterized OsMYB1R, a novel single repeat MYB transcription factor that acts as a transcriptional activator in sakuranetin biosynthesis. Protein-DNA binding and activation assays revealed that OsMYB1R directly regulates the gene promoter of OsNOMT, a key enzyme in sakuranetin synthesis. Molecular analyses and infection studies using OsMYB1R-overexpressing (OsMYB1R-OE) and OsMYB1R-knockout (Osmyb1r, generated using CRISPR/Cas9) plants demonstrated that OsMYB1R increases sakuranetin production and decreases Magnaporthe oryzae infection by transcriptionally regulating OsNOMT expression. This finding indicates a positive regulation of sakuranetin biosynthesis and antifungal resistance by the OsMYB1R-OsNOMT crosstalk. Interestingly, the alteration of OsMYB1R expression did not affect yield-related agronomic traits. Our results reveal a novel and positive role of 1R-MYB in secondary metabolite biosynthesis and pathogen defense, suggesting that OsMYB1R is a potential gene for effectively enhancing rice resistance without compromising yield.

Sequential Induction of Drug Resistance and Characterization of an Initial Candida albicans Drug-Sensitive Isolate.

The pathogenic fungus Candida albicans is a leading agent of death in immunocompromised individuals with a growing trend of antifungal resistance. The purpose is to induce resistance to drugs in a sensitive C. albicans strain followed by whole-genome sequencing to determine mechanisms of resistance. Strains will be assayed for pathogenicity attributes such as ergosterol and chitin content, growth rate, virulence, and biofilm formation. We observed sequential increases in ergosterol and chitin content in fluconazole-resistant isolates by 78% and 44%. Surface thickening prevents the entry of the drug, resulting in resistance. Resistance imposed a fitness trade-off that led to reduced growth rates, biofilm formation, and virulence in our isolates. Sequencing revealed mutations in genes involved in resistance and pathogenicity such as ERG11, CHS3, GSC2, CDR2, CRZ2, and MSH2. We observed an increase in the number of mutations in key genes with a sequential increase in drug-selective pressures as the organism increased its odds of adapting to inhospitable environments. In ALS4, we observed two mutations in the susceptible strain and five mutations in the resistant strain. This is the first study to induce resistance followed by genotypic and phenotypic analysis of isolates to determine mechanisms of drug resistance.

Emerging trends of invasive yeast infections and azole resistance in Beijing intensive care units

Invasive fungal infections pose a substantial threat to patients in healthcare settings globally. Recent changes in the prevalence of fungal species and challenges in conducting reference antifungal susceptibility testing emphasize the importance of monitoring fungi and their antifungal resistance. A two-phase surveillance project was conducted in Beijing, China, involving 37 centers across 12 districts, from January 2012 to December 2013 and from January 2016 to December 2017. We found that the proportion of Candida albicans in intensive care units (ICUs) during 2016–2017 exhibited a significant decline compared to the 2012–2013 period, although it remained the most predominant pathogen. In contrast, the prevalence of Nakaseomyces glabratus (formerly Candida glabrata) and Candida tropicalis notably increased during the two-phase surveillance. The high prevalence of C. tropicalis and its resistance to azole drugs posed a serious threat to patients in ICUs. The pathogens causing invasive fungal infections in Beijing were relatively sensitive to echinocandins. While C. albicans continued to exhibit susceptibility to azoles, the resistance and growth rates of C. tropicalis towards azoles were particularly prominent. Concerns were raised due to the emergence of multiple, short-term isolates of Clavispora lusitaniae and Candida parapsilosis complex in neonatal ICUs, given their similarity in antifungal susceptibilities. Such occurrences point towards the potential for transmission and persisting presence of these pathogens within the ICU environment. Our study complements existing data on the epidemiology of invasive fungal infections. It is imperative to exercise cautious medication management for ICU patients in Beijing, paying particular attention to azole resistance in C. tropicalis.

Mapping the Global Spread of T. indotineae: An Update on Antifungal Resistance, Mutations, and Strategies for Effective Management.

The global spread of Trichophyton indotineae presents a pressing challenge in dermatophytosis management. This systematic review explores the current landscape of T. indotineae infections, emphasizing resistance patterns, susceptibility testing, mutational analysis, and management strategies. A literature search was conducted in November 2023 using Embase, PubMed, Scopus, and Web of Science databases. Inclusion criteria covered clinical trials, observational studies, case series, or case reports with T. indotineae diagnosis through molecular methods. Reports on resistance mechanisms, antifungal susceptibility testing, and management were used for data extraction. A total of 1148 articles were identified through the systematic search process, with 45 meeting the inclusion criteria. The global spread of T. indotineae is evident, with cases reported in numerous new countries in 2023. Tentative epidemiological cut-off values (ECOFFs) suggested by several groups provide insights into the likelihood of clinical resistance. The presence of specific mutations, particularly Phe397Leu, correlate with higher minimum inhibitory concentrations (MICs), indicating potential clinical resistance. Azole resistance has also been reported and investigated in T. indotineae, and is a growing concern. Nevertheless, itraconazole continues to be an alternative therapy. Recommendations for management include oral or combination therapies and individualized approaches based on mutational analysis and susceptibility testing. Trichophyton indotineae poses a complex clinical scenario, necessitating enhanced surveillance, improved diagnostics, and cautious antifungal use. The absence of established clinical breakpoints for dermatophytes underscores the need for further research in this challenging field.

Unleashing Fungicidal Forces: Exploring the Synergistic Power of Amphotericin B-Loaded Nanoparticles and Monoclonal Antibodies.

Fungal infections cause 1.7 million deaths annually, which can be attributed not only to fungus-specific factors, such as antifungal resistance and biofilm formation, but also to drug-related challenges. In this study, the potential of Amphotericin (AmB) loaded polymeric nanoparticles (AmB-NPs) combined with murine monoclonal antibodies (mAbs) (i.e., CC5 and DD11) was investigated as a strategy to overcome these challenges. To achieve this goal, AmB-NPs were prepared by nanoprecipitation using different polymers (polycaprolactone (PCL) and poly(D,L-lactide) (PLA)), followed by comprehensive characterization of their physicochemical properties and in vitro biological performance. The results revealed that AmB-loaded NPs exhibited no cytotoxicity toward mammalian cells (baby hamster kidney cells-BHK and human monocyte cells-THP-1). Conversely, both AmB-NPs demonstrated a cytotoxic effect against C. albicans, C. neoformans, and H. capsulatum throughout the entire evaluated range (from 10 µg/mL to 0.1 µg/mL), with a significant MIC of up to 0.031 µg/mL. Moreover, the combination of AmB-NPs with mAbs markedly intensified antifungal activity, resulting in a synergistic effect that was two to four times greater than that of AmB-NPs alone. These findings suggest that the combination of AmB-NPs with mAbs could be a promising new treatment for fungal infections that is potentially more effective and less toxic than current antifungal treatments.

Management of invasive candidiasis: A focus on rezafungin, ibrexafungerp, and fosmanogepix.

Management of invasive fungal infections is challenging with growing antifungal resistance. Broad antifungal use has resulted in greater intrinsic and acquired resistance among Candida spp. It is important for clinicians to recognize the relationship between host susceptibility, site of infection, Candida resistance profiles, specific drug pharmacokinetics and pharmacodynamics, and the role of novel antifungal agents. This narrative review covers the role of rezafungin, ibrexafungerp, and fosmanogepix in the management of invasive candidiasis (IC). The PubMed Database, Embase, and ClinicalTrials.gov were searched between January 2006 and January 2024 using the following terms: rezafungin, CD101, ibrexafungerp, SCY-078, fosmanogepix, APX001, candidemia, and invasive candidiasis. Review articles, prospective clinical trials, and observational studies published in the English language were reviewed. Studies evaluating pharmacology, pharmacokinetics, efficacy, and safety in animals and humans were also reviewed. Promising data continues to emerge in support of novel drug therapies for IC and candidemia. Rezafungin possesses a unique pharmacodynamic profile that might be advantageous compared to other echinocandins, with a practical, once-weekly dosing interval. Ibrexafungerp, currently approved for vulvovaginal candidiasis, has been studied off-label for use in IC and candidemia, and initial data is encouraging. Lastly, fosmanogepix, a mechanistically novel, investigational antifungal agent, may be a potential future option in the management of IC and candidemia. Future research is needed to evaluate the potential use of these agents among diverse patient populations.

Antifungal Susceptibility Pattern of Fungi Isolated from Patients with Otomycosis Attending a Tertiary Health Care Institution in Sokoto, Nigeria

Abstract Background: Antifungal therapy is an important component of patient management for acute and chronic mycoses. However, treatment choices are restricted because of the scanty number of antifungal drug classes. Medical treatment of otomycosis is further compromised by the emergence of antifungal drug resistance, and these limits available drug classes as treatment options. Once considered a rare occurrence, antifungal drug resistance is on the rise in many high-risk medical centers. Most concerning is the evolution of multidrug-resistant organisms refractory to several different classes of antifungal agents, especially among common Candida species. Aim: This study seeks to identify the fungal species implicated in otomycosis among patients attending a tertiary health-care institution in Sokoto, Nigeria and determine its susceptibility pattern using commonly used antifungal agents. Methods: A descriptive, cross-sectional, hospital-based study was conducted on 100 patients with otitis externa. The ear discharge specimens were collected and analyzed using the standard microbial techniques. The antibiotic susceptibility profiles were determined for 12 different antifungal by the standard disk diffusion method. Data were analyzed using the SPSS software version 25 and the P < 0.05 was considered as statistically significant. Results: One hundred and twenty-four external ear discharge samples were collected from either right ear, left ear, or both ears (some patients has unilateral while others have bilateral disease and those with bilateral disease, samples were taken from the two ears). Aspergillus niger 30 (40.0%) was the most commonly isolated fungi in this study, followed by Candida spp. 25 (33.3%), Aspergillus fumigatus 5 (6.7%), Mucor 5 (6.7%), Penicillum 4 (5.3%), Aspergillus flavus 3 (4.0%), and Rhizopus 3 (4.0%) %). The isolated fungi were tested for antifungal sensitivity to 6 antifungal discs. A. niger shows good susceptibility to clotrimazole (100%), nystatin (90%), and fluconazole (83.3%) but was resistant to griseofulvin, terbinafine, and ketoconazole. A. flavus and A. fumigatus also show good sensitivity to clotrimazole, nystatin, and fluconazole. Candida albicans was only susceptible to clotrimazole but resistant to other tested antifungal disc. Rhizopus and Penicillum species showed 100.0% sensitivity to clotrimazole but also resistant to other tested antifungal discs. Conclusions: This study revealed that Aspergillus and Candida species were the most common fungal pathogens causing otomycosis. A. niger is the predominant fungal isolate. Molds isolates showed good susceptibility to clotrimazole, while highest resistance was to terbinafine and ketoconazole. Yeasts isolates showed highest susceptibility to clotrimazole and highest resistance to nystatin and fluconazole.

Insights into invasive fungal infection diagnostic and treatment capacities in tertiary care centres of Germany.

In Germany, the growing incidence of invasive fungal infections (IFIs) is a significant health concern, particularly impacting individuals with compromised immune systems due to factors like increasing transplant recipients, an ageing population, and heightened use of immunosuppressive medications. Diagnosing IFI remains challenging, and the integration of biomarker assays into clinical practice is difficult. Antifungal resistance, exemplified by pan-antifungal-resistant Candida auris cases, adds complexity to treatment. This study aims to provide a concise overview of the diagnostic and treatment landscape for IFI in Germany, identifying areas for improvement and paving the way for targeted interventions. Data were collected using an online electronic case report form from October 2021 to February 2023. The survey included questions about institutional practices related to fungal infection diagnosis and treatment, with invitations extended to researchers nationwide. The study surveyed 58 hospitals across Germany. Notably, 77.6% managed high-risk patients for IFI. While 86% had onsite microbiology labs, a significant difference was noted for high-risk patients (93% in specialized hospitals versus 62% in others). Microscopy services had 96% coverage, while overall access to culture was 96%. Antigen tests had 96% coverage, and antibody access was reported at 98%. PCR testing was available at 98%. Imaging access showed no significant access differences. Variability existed in amphotericin B formulations based on patient profiles. Therapeutic drug monitoring was more common in high-risk patient institutions (89.5% versus 50.0%). All analysed institutions reported access to surgery (100%). Addressing identified disparities in diagnostic and therapeutic resources for IFI is crucial to improving patient outcomes. The study calls for ongoing research and collaboration to optimize strategies for the prevention and treatment of IFI, emphasizing the importance of equitable access to resources, especially in high-risk patient populations.

Exploring European Consensus About the Remaining Treatment Challenges and Subsequent Opportunities to Improve the Management of Invasive Fungal Infection (IFI) in the Intensive Care Unit

BackgroundThe global prevalence of invasive fungal infections (IFI) is increasing, particularly within Intensive Care Units (ICU), where Candida spp. and Aspergillus spp. represent the most important pathogens. Diagnosis and management of IFIs becomes progressively challenging, with increasing antifungal resistance and the emergence of rare fungal species.Through a consensus survey focused on assessing current views on how IFI should be managed, the aim of this project was to identify challenges around diagnosing and managing IFIs in the ICU. The current status in different countries and perceived challenges to date amongst a multidisciplinary cohort of healthcare professionals involved in the care of IFI in the ICU was assessed.MethodsUsing a modified Delphi approach, an expert panel developed 44 Likert-scale statements across 6 key domains concerning patient screening and minimal standards for diagnosis of IFIs in ICU; initiation and termination of antifungal treatments and how to minimise their side effects and insights for future research on this topic. These were used to develop an online survey which was distributed on a convenience sampling basis utilising the subscriber list held by an independent provider (M3 Global). This survey was distributed to intensivists, infectious disease specialists, microbiologists and antimicrobial/ICU pharmacists within the UK, Germany, Spain, France and Italy. The threshold for consensus was set at 75%.ResultsA total of 335 responses were received during the five-month collection period. From these, 29/44 (66%) statements attained very high agreement (≥ 90%), 11/44 (25%) high agreement (< 90% and ≥ 75%), and 4/44 (9%) did not meet threshold for consensus (< 75%). ConclusionThe results outline the need for physicians to be aware of the local incidence of IFI and the associated rate of azole resistance in their ICUs. Where high clinical suspicion exists, treatment should start immediately and prior to receiving the results from any diagnostic test. Beta-D-glucan testing should be available to all ICU centres, with results available within 48 h to inform the cessation of empirical antifungal therapy. These consensus statements and proposed measures may guide future areas for further research to optimise the management of IFIs in the ICU.

Genetic Mutations in FKS1 Gene Associated with Acquired Echinocandin Resistance in Candida parapsilosis Complex.

Candida parapsilosis complex has recently received special attention due to naturally occurring FKS1 polymorphism associated with high minimal inhibitory concentrations for echinocandin and the increase of clonal outbreaks of strains resistant to commonly used antifungals such as fluconazole. Despite the previous fact, little is known about the genetic mechanism associated with echinocandin resistance. Therefore, the present study was designed to investigate the mechanism of acquired echinocandin resistance in C. parapsilosis complex strains. A total of 15 clinical C. parapsilosis complex isolates were sub-cultured for 30days at a low concentration of micafungin at ½ the lowest MIC value of the tested isolates (0.12µg/ml). After culturing, all the isolates were checked phenotypically for antifungal resistance and genotypically for echinocandin resistance by checking FKS1 gene hot spot one (HS1) and HS2 mutations. In vitro induction of echinocandin resistance confirmed the rapid development of resistance at low concentration micafungin, with no difference among C. parapsilosis, C. metapsilosis, and C. orthopsilosis in the resistance development. For the first time we identified different FKS1 HS1 and or HS2 mutations responsible for echinocandin resistance such as R658S and L1376F in C. parapsilosis, S656X, R658X, R658T, W1370X, X1371I, V1371X, and R1373X (corresponding to their location in C. parapsilosis) in C. metapsilosis, and L648F and R1366H in C. orthopsilosis. Our results are of significant concern, since the rapid development of resistance may occur clinically after short-term exposure to antifungals as recently described in other fungal species with the potential of untreatable infections.

Antifungal Susceptibility and Genotypic Analysis of cyp51A Mutations in Aspergillus fumigatus Isolates in Malaysia.

Azole resistance in Aspergillus fumigatus poses a significant challenge in the management of invasive aspergillosis. This study aimed to investigate the antifungal susceptibility and cyp51A mutation profiles of A. fumigatus isolates in Malaysia. Sixty clinical A. fumigatus isolates were collected and subjected to antifungal susceptibility testing (AFST) and molecular analysis. The antifungal susceptibility testing was performed according to CLSI M38 guideline. The geometric mean (GM) minimum inhibitory concentration (MIC), MIC50/MIC90 for voriconazole, itraconazole, posaconazole, amphotericin B, and isavuconazole against A. fumigatus in non-invasive cases and invasive cases were calculated. In addition, the presence of cyp51A mutations was also identified. The present study revealed an overall resistance rate of 6.7% among the isolates. In non-invasive cases, isavuconazole and posaconazole demonstrated the lowest GM MIC of 0.08 µg/mL. Following them were itraconazole, voriconazole, and amphotericin B with concentrations of 0.15µg/mL, 0.16µg/mL and 0.90µg/mL, respectively. Similarly, in invasive cases, isavuconazole and posaconazole exhibited the lowest GM MIC of 0.09µg/mL. Following them were itraconazole, voriconazole, and amphotericin B with concentrations of 0.14µg/mL, 0.17µg/mL and 0.80µg/mL, respectively. Genotypic analysis revealed various cyp51A mutations, including F46Y, M172V, N248K, R34L, V244A, V244S, and E427K. However, not all mutations corresponded to antifungal resistance. The majority of clinical Aspergillus fumigatus isolates demonstrated susceptibility to the antifungal agents tested, with isavuconazole and posaconazole demonstrating the lowest MIC values. However, cyp51A mutations were discovered without a consistent correlation to antifungal resistance, emphasising the need for additional research.

Distribution and antifungal resistance profile of Candida spp. isolated from patients living with HIV at the Yaoundé Central Hospital

Distribution and antifungal resistance profile of Candida spp. isolated from patients living with HIV at the Yaoundé Central Hospital

Candida Non-albicans and Non-auris Causing Invasive Candidiasis in a Fourth-Level Hospital in Colombia: Epidemiology, Antifungal Susceptibility, and Genetic Diversity.

Increasingly common and associated with healthcare settings, Candida infections are very important, since some species of this genus can develop antifungal resistance. We contribute data on the epidemiology, antifungal susceptibility, and genetic diversity of Candida non-albicans and non-auris affecting critically ill patients in a fourth-level hospital in Colombia. Ninety-seven isolates causing invasive infections, identified by conventional methods over 18 months, were studied. Data from patients affected by these yeasts, including sex, age, comorbidities, treatment, and outcome, were analysed. The antifungal susceptibility of the isolates was determined, and the ribosomal DNA was sequenced. Candida parapsilosis, Candida tropicalis, Candida glabrata, Candida dubliniensis, and Candida guilliermondii caused 48.5% of all cases of invasive candidiasis. The species were mainly recovered from blood (50%). Patients were mostly men (53.4%), between 18 days and 93 years old, hospitalized in the ICU (70.7%). Overall mortality was 46.6%, but patients in the ICU, using antibiotics, with diabetes mellitus, or with C. glabrata infections were more likely to die. Resistant isolates were identified in C. parapsilosis, C. tropicalis, and C. glabrata. This study provides epidemiological data for the surveillance of emerging Candida species, highlighting their clinical impact, as well as the emergence of antifungal resistance and clonal dispersal.

Species distribution and antimicrobial sensitivity pattern of etiologic agents in patients with neonatal sepsis, National Children’s Hospital, Ha Noi, Vietnam, 2019–2021

Neonatal sepsis is one of the significant causes of morbidity and mortality in neonates, especially in developing countries. This study investigates the species distribution and antimicrobial susceptibility pattern of agents causing neonatal sepsis in a northern hospital in Vietnam. Materials and methods. All in-term neonates treated at the Neonatal Center, National Children’s Hospital, Vietnam between December 2019, and April 2021 who met the clinical criteria for sepsis and positive blood cultures were enrolled. Species identification and antimicrobial susceptibility testing were performed with Vitek 2 Compact (bioMerieux, France). Results. Eighty-five neonates were included with the majority of cases being early-onset sepsis (61.2%, 95% CI: 50.6–71.8%). Gram-negative, Gram-positive, and fungal isolates constituted 50.6%, 40%, and 9.4%, respectively. The most common agent was Staphylococcus aureus (28.2%) followed by Klebsiella pneumoniae and Escherichia coli (16.5% each). For those with bacteriological sepsis, Gram-negative pathogens were predominant in early-onset sepsis whereas Gram-positive pathogens were predominant in late-onset sepsis (75.0% (33/44) vs 69.7% (23/33), p 0.001). Antibiotic resistance was common among bacterial isolates, but antifungal resistance was not detected among isolates of Candida sp. Vancomycin and fluoroquinolone were very effective against Gram-positive organisms while piperacillin + tazobactam, aztreonam, and ertapenem were potent drugs against Gram-negative organisms. Conclusion. Routine investigation of microbial profiles and antimicrobial susceptibility patterns is essential to guiding strategies for the choices of empirical antimicrobials.

Secreted Aspartic Proteinases: Key Factors in Candida Infections and Host-Pathogen Interactions.

Extracellular proteases are key factors contributing to the virulence of pathogenic fungi from the genus Candida. Their proteolytic activities are crucial for extracting nutrients from the external environment, degrading host defenses, and destabilizing the internal balance of the human organism. Currently, the enzymes most frequently described in this context are secreted aspartic proteases (Saps). This review comprehensively explores the multifaceted roles of Saps, highlighting their importance in biofilm formation, tissue invasion through the degradation of extracellular matrix proteins and components of the coagulation cascade, modulation of host immune responses via impairment of neutrophil and monocyte/macrophage functions, and their contribution to antifungal resistance. Additionally, the diagnostic challenges associated with Candida infections and the potential of Saps as biomarkers were discussed. Furthermore, we examined the prospects of developing vaccines based on Saps and the use of protease inhibitors as adjunctive therapies for candidiasis. Given the complex biology of Saps and their central role in Candida pathogenicity, a multidisciplinary approach may pave the way for innovative diagnostic strategies and open new opportunities for innovative clinical interventions against candidiasis.

Determination of Metalloprotease Gene in a Few Dermatophyte Species and Its Relationship with Antifungal Resistance

Determination of Metalloprotease Gene in a Few Dermatophyte Species and Its Relationship with Antifungal Resistance

New Amino Acids Naphthalene Scaffolds as Potent Antimicrobial Agents: In Vitro Assay and In Silico Molecular Docking Study

AbstractThe development of innovative antifungal medications to address the issues of indiscriminate antifungal use contributes to certain antifungal drug resistance. To tackle this issue, we have designed and synthesized novel amino acids naphthalene scaffolds (6 a–6 i) (Scheme 1) by acid amine coupling between compound 5 and various amino acids. Moreover, we evaluated the antifungal, anti‐bacterial and antimalarial activities of synthesized derivatives. Among them, compounds Met (6 a), Phe (6 c), Lys (6 d), Ser (6 f), and Tyr (6 i) expressed excellent antifungal activity at a minimum inhibitory concentration (MIC) value of 250 μg/mL against Candida albicans compared to standard drug griseofulvin (500 μg/mL). The antibacterial assay results showed that compound Met (6 a) exhibited effective antibacterial activity at MIC value at 50 and 62.5 μg/mL against Streptococcus pyogenes and Pseudomonas aeruginosa respectively, and compound Trp (6 g) showed very good antibacterial activity at MIC 62.5 μg/mL against Staphylococcus aureus. The antimalarial activity of synthesized compoundsVal (6 b) and Lys (6 d) showed moderately active with mean IC50 of 0.69 and 0.47 μg/mL, respectively compared with standard drug quinine (IC50=0.26 μg/mL). Also, a molecular docking study was performed to demonstrate the binding energy of synthesized scaffoldswith effective interaction with various proteins. The compound Met (6 a) showed that the highest binding affinity (binding energy: −7.1 kcal/mol) which interacted more effectively with VAL 120 (2.90 Å).