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Background: Fluconazole-resistant Candida parapsilosis is a matter of concern.

Objectives: To describe fluconazole-resistant C. parapsilosis genotypes circulating across hospitals in Spain and Rome and to study their azole-resistance profile associated with ERG11p substitutions.

Patients/methods: We selected fluconazole-resistant C. parapsilosis isolates (n = 528 from 2019 to 2023; MIC ≥8 mg/L according to EUCAST) from patients admitted to 13 hospitals located in five Spanish cities and Rome. Additionally, we tested voriconazole, posaconazole, isavuconazole, amphotericin B, micafungin, anidulafungin and ibrexafungerp susceptibility.

Results: Of the 53 genotypes found, 49 harboured the Y132F substitution, five of which were dominating city-specific genotypes involving almost half the isolates. Another genotype involved isolates harbouring the G458S substitution. Finally, we found two genotypes with the wild-type ERG11 gene sequence and one with the R398I substitution. All isolates were fully susceptible/wild-type to amphotericin B, anidulafungin, micafungin and ibrexafungerp. The azole-resistance patterns found were: voriconazole-resistant (74.1%) or voriconazole-intermediate (25.2%), posaconazole-resistant (10%) and isavuconazole non-wild-type (47.5%). Fluconazole-resistant and voriconazole non-wild-type isolates were likely to harbour substitution Y132F if posaconazole was wild type; however, if posaconazole was non-wild type, substitution G458S was indicated if isavuconazole MIC was >0.125 mg/L or substitution Y132F if isavuconazole MIC was ≤0.125 mg/L.

Conclusions: We detected a recent clonal spread of fluconazole-resistant C. parapsilosis across some cities in Spain, mostly driven by dominating city-specific genotypes, which involved a large number of isolates harbouring the Y132F ERG11p substitution. Isolates harbouring substitution Y132F can be suspected because they are non-susceptible to voriconazole and rarely posaconazole-resistant.

Background: Onychomycoses are difficult-to-treat fungal infections with high relapse rates. Combining oral and topical antifungal drugs is associated with higher success rates. Additive or synergistic modes of action are expected to enhance treatment success rates.

Objectives: Investigation of the combined effects of antifungal drugs in vitro with different modes of action and application on clinical isolates from mycotic nails.

Methods: Isolates of Trichophyton rubrum, Trichophyton interdigitale and Scopulariopsis brevicaulis were collected from infected toenail specimens of patients with onychomycosis. Susceptibility testing was performed in 96-well polystyrene plates using a standard stepwise microdilution protocol. Additive or synergistic activity at varying concentrations was investigated by the checkerboard method.

Results: Combining terbinafine with amorolfine tended to be more effective than terbinafine in conjunction with ciclopirox. In most combinations, additive effects were observed. Synergy was detected in combinations with involving amorolfine in S. brevicaulis. These additive and synergistic interactions indicate that combined therapy with topical amorolfine and oral terbinafine is justified. Sublimation of amorolfine (and terbinafine) may enhance the penetration in and through the nail plate, and support treatment efficacy.

Conclusions: These in vitro results support the notion that combining oral terbinafine and topical amorolfine is beneficial to patients with onychomycosis, particularly if the pathogen is a non-dermatophyte fungus such as S. brevicaulis.

Background: Candida species are among the most important invasive pathogens in intensive care units (ICUs). Non-albicans species including Candida parapsilosis (C. parapsilosis) has increased in recent years. Fluconazole is the leading antifungal agent but resistance is a concern among C. parapsilosis species.

Objectives: The aim of this study was to determine the factors associated with fluconazole resistance in patients with candidemia due to C. parapsilosis in ICUs.

Methods: This case-case study was conducted in a 750-bed, tertiary hospital between 2015 and 2021. Patients with fluconazole-resistant C. parapsilosis candidemia constituted the 'cases of interest' group and patients with fluconazole-susceptible C. parapsilosis candidemia constituted the 'comparison cases' group. Demographic and clinical data of the patients were recorded. Logistic regression analysis was performed using the backward elimination method to determine the independent predictors of fluconazole-resistant C. parapsilosis bloodstream infections.

Results: The study included 177 patients. In the cultures of these patients, 76 (43%) fluconazole-resistant, 13 (7.3%) fluconazole-reduced susceptible, and 88 (49.7%) fluconazole-susceptible isolates were found. In the regression analysis the risk factors for fluconazole-resistant C. parapsilosis bloodstream infection, malignancy, immunosuppressive treatment, history of intra-abdominal surgery, hypoalbunemia, previous fluconazole use, and SOFA score were found to be associated in univariate analysis. In multivariate regression analysis, history of intra-abdominal surgery (OR: 2.16; 95% CI: 1.05-4.44), hypoalbuminemia (OR: 2.56; 95% CI: 1.06-6.17) and previous fluconazole use (OR: 3.35; 95% CI: 1.02-11) were found to be independent predictors.

Conclusions: In this study, a significant correlation was found between candidemia due to fluconazole-resistant C. parapsilosis in ICUs and intra-abdominal surgery, hypoalbuminemia, and previous fluconazole use. C. parapsilosis isolates and fluconazole resistance should be continuously monitored, strict infection control measures should be taken and antifungal stewardship programs should be implemented.

Background: Autosomal recessive deficiency in the caspase recruitment domain-containing protein 9 (CARD9) is a congenital immunological condition that leads to susceptibility to mucocutaneous and invasive fungal infections. There is growing incidence of fungal infections in patients with CARD9 deficiency, a phenomenon that is increasingly recognised.

Objectives: This study aimed to assess the frequency, geographic distribution and nature of mutations in patients with CARD9 deficiency, based on published papers in the literature until March 2023.

Methods: We swiftly conducted a study to pinpoint every documented instance of fungal infections arising from CARD9 deficiency. We selected case reports from the databases of PubMed, Embase, Scopus and Google Scholar spanning the period from October 2009 to March 2023.

Results: We analysed 90 cases of fungal infections and identified 32 mutations in the CARD9 gene. Notably, the homozygous (HMZ) p.Q295X (c.883C > T) mutation was associated with an increased risk of candidiasis. In contrast, the HMZ p.Q289X (c.865C > T) mutation is linked to a higher risk of dermatophytosis. We observed differences in the geographical distribution of these mutations. The primary mutations found in African patients differ from those in Asian patients. Specifically, Asian patients exhibit a broader spectrum of CARD9 mutations than African patients.

Conclusions: The diversity of mutations observed in the 90 cases revealed 32 distinct variations, emphasising the unique genetic alterations in the CARD9 gene associated with specific geographical areas and the corresponding prevalence of fungal infections.

Background: Post-tuberculosis lung abnormality (PTLA) is the most common risk factor for developing chronic pulmonary aspergillosis (CPA). However, the prevalence and incidence of CPA in PTLA patients in India remain unknown.

Objectives: We aimed to ascertain the incidence and prevalence of CPA in subjects with PTLA.

Methods: We identified a cohort of pulmonary tuberculosis who completed anti-tuberculosis therapy (ATT) before November 2019 from the records of the 12 tuberculosis treatment centers attached to the national program. We recorded the clinical and demographic details. We performed computed tomography (CT) of the chest and estimated serum A. fumigatus-specific IgG. We categorised subjects as PTLA with or without CPA using a composite of clinical, radiological, and microbiological features. We resurveyed the subjects at 6 months (or earlier) for the presence of new symptoms. We calculated the prevalence and the incidence rate (per 100-person years) of CPA.

Results: We included 117 subjects with PTLA, with a median of 3 years after ATT completion. Eleven subjects had CPA in the initial survey, and one additional case developed CPA during the second survey. The prevalence of CPA in PTLA subjects was 10.3% (12/117). The total observation period was 286.7 person-years. The median (interquartile range) time to develop CPA after ATT completion was 12.5 (5-36.7) months. We found the CPA incidence rate (95% confidence interval) of 4.2 (1.8-6.5) per 100-person years.

Conclusion: Chronic pulmonary aspergillosis complicates 10% of PTLA subjects after successful outcomes with ATT. Four new CPA cases may develop per 100-persons years of observation after ATT completion. We suggest screening patients with PTLA who develop new symptoms for CPA.

Background: Meyerozyma guilliermondii is a yeast species responsible for invasive fungal infections. It has high minimum inhibitory concentrations (MICs) to echinocandins, the first-line treatment of candidemia. In this context, azole antifungal agents are frequently used. However, in recent years, a number of azole-resistant strains have been described. Their mechanisms of resistance are currently poorly studied.

Objective: The aim of this study was consequently to understand the mechanisms of azole resistance in several clinical isolates of M. guilliermondii.

Methods: Ten isolates of M. guilliermondii and the ATCC 6260 reference strain were studied. MICs of azoles were determined first. Whole genome sequencing of the isolates was then carried out and the mutations identified in ERG11 were expressed in a CTG clade yeast model (C. lusitaniae). RNA expression of ERG11, MDR1 and CDR1 was evaluated by quantitative PCR. A phylogenic analysis was developed and performed on M. guilliermondii isolates. Lastly, in vitro experiments on fitness cost and virulence were carried out.

Results: Of the ten isolates tested, three showed pan-azole resistance. A combination of F126L and L505F mutations in Erg11 was highlighted in these three isolates. Interestingly, a combination of these two mutations was necessary to confer azole resistance. An overexpression of the Cdr1 efflux pump was also evidenced in one strain. Moreover, the three pan-azole-resistant isolates were shown to be genetically related and not associated with a fitness cost or a lower virulence, suggesting a possible clonal transmission.

Conclusion: In conclusion, this study identified an original combination of ERG11 mutations responsible for pan-azole-resistance in M. guilliermondii. Moreover, we proposed a new MLST analysis for M. guilliermondii that identified possible clonal transmission of pan-azole-resistant strains. Future studies are needed to investigate the distribution of this clone in hospital environment and should lead to the reconsideration of the treatment for this species.

Background: Invasive pulmonary aspergillosis (IPA) is a relatively common infection in patients with acute myeloid leukaemia (AML), and is associated with high mortality rates. Optimising early detection is key to reduce the burden of IPA in this population. In this retrospective cohort study, we evaluated the added value of baseline chest CT before start of classical induction chemotherapy.

Methods: Adult patients receiving first-line intensive chemotherapy for AML were included if a baseline chest CT scan was available (±7 days). Data were collected from the electronic health record. IPA was classified using the EORTC/MSGERC 2020 consensus definitions.

Results: Between 2015 and 2019, 99 patients were included. During first-line treatment, 29/99 (30%) patients developed a probable IPA. Baseline chest CT was abnormal in 61/99 (62%) and 14/61 (23%) patients had typical radiological signs for IPA. An abnormal scan showed a trend towards higher risk for IPA (hazard ratio (HR): 2.12; 95% CI 0.95-4.84). Ground glass opacities were a strong predictor for developing IPA (HR 3.35: 95% CI 1.61-7.00). No probable/proven IPA was diagnosed at baseline; however, a bronchoalveolar lavage (BAL) at baseline was only performed in seven patients. Twelve-week mortality was higher in patients with IPA (7/26, 27% vs. 5/59, 8%; p = .024).

Conclusion: Baseline chest CT scan could be an asset in the early diagnosis of IPA and contribute to risk estimation for IPA. In patients with an abnormal baseline CT, performing a BAL should be considered more frequently, and not only in patients with radiological findings typical for IPA.

Background: Cryptococcal meningitis (CM), an opportunistic fungal infection affecting immunocompromised hosts, leads to high mortality. The role of previous exposure to glucocorticoids as a risk factor and as an outcome modulator has been observed, but systematic studies are lacking.

Objective: The primary aim of this study is to evaluate the impact of glucocorticoid use on the clinical outcomes, specifically mortality, of non-HIV and non-transplant (NHNT) patients diagnosed with CM.

Methods: We queried a global research network to identify adult NHNT patients with CM based on ICD codes or recorded specific Cryptococcus CSF lab results with or without glucocorticoid exposure the year before diagnosis. We performed a propensity score-matched analysis to reduce the risk of confounding and analysed outcomes by glucocorticoid exposure. We used a Cox proportional hazards model for survival analysis.

Results: We identified 764 patients with a history of glucocorticoid exposure and 1267 patients without who developed CM within 1 year. After propensity score matching of covariates, we obtained 627 patients in each cohort. The mortality risk in 1 year was greater in patients exposed to prior glucocorticoids (OR: 1.3, CI: 1.2-2.0, p = 0.002). We found an excess of 45 deaths among CM patients with previous glucocorticoid use (7.4% increased absolute risk of dying within 1 year of diagnosis) compared to CM controls without glucocorticoid exposure. Hospitalisation, intensive care unit admission, emergency department visits, stroke and cognitive dysfunction also showed significant, unfavourable outcomes in patients with glucocorticoid-exposed CM compared to glucocorticoid-unexposed CM patients.

Conclusions: Previous glucocorticoid administration in NHNT patients seems to associate with 1-year mortality after CM adjusted for possible confounders related to demographics, comorbidities and additional immunosuppressive medications. Serial CrAg screening might be appropriate for higher-risk patients on glucocorticoids after further cost-benefit analyses.

Background: Dermatophytosis is an intractable superficial mycosis in humans and animals mainly caused by Trichophyton mentagrophytes (T. mentagrophytes), with a global prevalence of about 20%. Keratinocytes are the most abundant participants in skin immunity, and they also play a role in the first-line defence against T. mentagrophytes. However, no studies of keratinocyte responses against T. mentagrophytes infection based on the whole transcriptome have been reported.

Objectives: Here, we systematically analysed changes in keratinocytes infected with T. mentagrophytes using whole transcriptome sequencing technology.

Methods: The phenotypic changes in keratinocytes after infection with 1 × 10⁵ conidia/mL T. mentagrophytes were observed by light microscopy, scanning electron microscopy, transmission electron microscopy and terminal deoxynucleotidyl transferase dUTP nick end labeling. RNA-sequencing (RNA-seq), small RNA-seq technology and related bioinformatics methods were used to systematically analyse the whole transcriptome changes in keratinocytes upon T. mentagrophytes stimulation.

Results: We found that T. mentagrophytes infection caused morphological changes, membrane damage, the formation of irregular organelles and keratinocyte apoptosis. A total of 204 differentially expressed (DE) circular RNAs (circRNAs), 868 DE long noncoding RNAs (lncRNAs), 2973 DE mRNAs and 209 DE micro RNAs (miRNAs) were identified between noninfected and T. mentagrophytes-infected keratinocytes. The expression level of selected RNAs was validated by quantitative real-time polymerase chain reaction (qRT-PCR). Functional enrichment analysis revealed that the parental genes of DE circRNAs were related to cell response, cell death and establishment of the skin barrier. Genes targeted by miRNA were involved in regulating the initiation of the immune response. Based on the expression level of circRNAs, lncRNAs, mRNAs and miRNAs, circRNA-miRNA-mRNA competing endogenous (ceRNA) networks comprised of 159 DE miRNAs, 141 DE circRNAs and 2307 DE mRNAs, and lncRNA-miRNA-mRNA ceRNA networks comprised of 790 DE lncRNAs, 190 DE miRNAs and 2663 DE mRNAs were constructed. The reliability of two selected ceRNA networks was verified using qRT-PCR. Further functional enrichment analysis revealed that the DE mRNAs interacting with circRNAs and lncRNAs in the ceRNA network mainly participated in fungal recognition, inflammation, the innate immune response and the death of keratinocytes.

Conclusions: Our findings might provide new evidence on the pathogenesis of T. mentagrophytes-induced dermatophytosis, which is essential for identifying new therapeutic targets for dermatophytosis treatment.