Candida albicans is one of the agents of invasive candidiasis, a life-threatening disease strongly associated with hospitalization, particularly among patients in intensive care units with central venous catheters. This study aimed to evaluate the synergistic activity of the antifungal peptide ToAP2 combined with fluconazole against C. albicans biofilms grown on various materials. We tested combinations of different concentrations of the peptide ToAP2 with fluconazole on C. albicans biofilms. These biofilms were generated on 96-well plates, intravenous catheters, and infusion tubes in RPMI medium at two maturation stages. Scanning electron microscopy and atomic force microscopy were employed to assess the biofilm structure. We also evaluated the expression of genes previously proven to be involved in C. albicans biofilm formation in planktonic and biofilm cells after treatment with the peptide ToAP2 using qPCR. ToAP2 demonstrated a synergistic effect with fluconazole at concentrations up to 25 µM during both the early and mature stages of biofilm formation in 96-well plates and on medical devices. Combinations of 50, 25, and 12.5 µM of ToAP2 with 52 µM of fluconazole significantly reduced the biofilm viability compared to individual treatments and untreated controls. These results were supported by substantial structural changes in the biofilms observed through both scanning and atomic force microscopy. The gene expression analysis of C. albicans cells treated with 25 µM of ToAP2 revealed a decrease in the expression of genes associated with membrane synthesis, along with an increase in the expression of genes involved in efflux pumps, adhesins, and filamentation. Our results highlight the efficacy of the combined ToAP2 and fluconazole treatment against C. albicans biofilms. This combination not only shows therapeutic potential but also suggests its utility in developing preventive biofilm tools for intravenous catheters.

Fonsecaea pedrosoi is a melanized fungus that causes chromoblastomycosis (CBM), a tropical neglected disease responsible for chronic and disability-related subcutaneous mycosis. Given the challenging nature of CBM treatment, the study of new targets and novel bioactive drugs capable of improving patient life quality is urgent. In the present work, we detected a calcineurin activity in F. pedrosoi conidial form, employing primarily colorimetric, immunoblotting and flow cytometry assays. Our findings reveal that the calcineurin activity of F. pedrosoi was stimulated by Ca2+/calmodulin, inhibited by EGTA and specific inhibitors, such as tacrolimus (FK506) and cyclosporine A (CsA), and proved to be insensitive to okadaic acid. In addition, FK506 and CsA were able to affect the cellular viability and the fungal proliferation. This effect was corroborated by transmission electron microscopy that showed both calcineurin inhibitors promoted profound changes in the ultrastructure of conidia, causing mainly cytoplasm condensation and intense vacuolization that are clear indication of cell death. Our data indicated that FK506 exhibited the highest effectiveness, with a minimum inhibitory concentration (MIC) of 3.12 mg/L, whereas CsA required 15.6 mg/L to inhibit 100% of conidial growth. Interestingly, when both were combined with itraconazole, they demonstrated anti-F. pedrosoi activity, exhibiting a synergistic effect. Moreover, the fungal filamentation was affected after treatment with both calcineurin inhibitors. These data corroborate with other calcineurin studies in fungal cells and open up further discussions aiming to establish the role of this enzyme as a potential target for antifungal therapy against CBM infections.

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UNASSIGNED: The increasing prevalence of fungal infections necessitates broader use of antifungal medications. However, the prevalence of adverse drug events (ADEs) restricts their clinical application. This study aimed to develop a reliable ADEs trigger for antifungals to enable proactive ADEs monitoring, serving as a reference for ADEs prevention and control.
UNASSIGNED: This investigation comprises two phases. Initially, the trigger was established via a literature review, extraction of relevant items, and refinement through Delphi expert consultation. Subsequently, the validity of the trigger was assessed by analyzing hospital records of antifungal drug users from 1 January 2019 to 31 December 2020. The correlation between each trigger signal and ADEs occurrence was examined, and the sensitivity and specificity of the trigger were evaluated through the spontaneous reporting system (SRS) and Global Trigger Tool (GTT). Additionally, risk factors contributing to adverse drug events (ADEs) resulting from antifungal use were analyzed. Results: Twenty-one preliminary triggers were refined into 21 final triggers after one expert round. In the retrospective analysis, the positive trigger rate was 65.83%, with a positive predictive value (PPV) of 28.75%. The incidence of ADEs in inpatients was 28.75%, equating to 44.58 ADEs per 100 admissions and 33.04 ADEs per 1,000 patient days. Predominant ADEs categories included metabolic disturbances, gastrointestinal damage, and skin rashes. ADEs severity was classified into 36 cases at grade 1, 160 at grade 2, and 18 at grade 3. The likelihood of ADEs increased with longer stays, more positive triggers, and greater comorbidity counts.
UNASSIGNED: This study underscores the effectiveness of the GTT in enhancing ADEs detection during antifungal medication use, thereby confirming its value as a monitoring tool.

Cryptococcus neoformans is at the top of the list of \"most wanted\" human pathogens. Only three classes of antifungal drugs are available for the treatment of cryptococcosis. Studies on antifungal resistance mechanisms are limited to the investigation of how a particular antifungal drug induces resistance to a particular drug, and the impact of stresses other than antifungals on the development of antifungal resistance and even cross-resistance is largely unexplored. The endoplasmic reticulum (ER) is a ubiquitous subcellular organelle of eukaryotic cells. Brefeldin A (BFA) is a widely used chemical inducer of ER stress. Here, we found that both weak and strong selection by BFA caused aneuploidy formation in C. neoformans, mainly disomy of chromosome 1, chromosome 3, and chromosome 7. Disomy of chromosome 1 conferred cross-resistance to two classes of antifungal drugs: fluconazole and 5-flucytosine, as well as hypersensitivity to amphotericin B. However, drug resistance was unstable, due to the intrinsic instability of aneuploidy. We found overexpression of AFR1 on Chr1 and GEA2 on Chr3 phenocopied BFA resistance conferred by chromosome disomy. Overexpression of AFR1 also caused resistance to fluconazole and hypersensitivity to amphotericin B. Furthermore, a strain with a deletion of AFR1 failed to form chromosome 1 disomy upon BFA treatment. Transcriptome analysis indicated that chromosome 1 disomy simultaneously upregulated AFR1, ERG11, and other efflux and ERG genes. Thus, we posit that BFA has the potential to drive the rapid development of drug resistance and even cross-resistance in C. neoformans, with genome plasticity as the accomplice.

As comparative pharmacokinetic/pharmacodynamic (PK/PD) studies of liposomal amphotericin B (L-AMB) against Candida spp. are lacking, we explored L-AMB pharmacodynamics against different Candida species in an in vitro PK/PD dilution model. Eight Candida glabrata, Candida parapsilosis, and Candida krusei isolates (EUCAST/CLSI AMB MIC 0.125-1 mg/L) were studied in the in vitro PK/PD model simulating L-AMB Cmax = 0.25-64 mg/L and t1/2 = 9 h. The model was validated with one susceptible and one resistant Candida albicans isolate. The Cmax/MIC-log10CFU/mL reduction from the initial inoculum was analyzed with the Emax model, and Monte Carlo analysis was performed for the standard (3 mg/kg with Cmax = 21.87 ± 12.47 mg/L) and higher (5 mg/kg with Cmax = 83 ± 35.2 mg/L) L-AMB dose. A ≥1.5 log10CFU/mL reduction was found at L-AMB Cmax = 8 mg/L against C. albicans, C. parapsilosis, and C. krusei isolates (MIC 0.25-0.5 mg/L) whereas L-AMB Cmax ≥ 32 mg/L was required for C. glabrata isolates. The in vitro PK/PD relationship followed a sigmoidal pattern (R2 ≥ 0.85) with a mean Cmax/MIC required for stasis of 2.1 for C. albicans (close to the in vivo stasis), 24/17 (EUCAST/CLSI) for C. glabrata, 8 for C. parapsilosis, and 10 for C. krusei. The probability of target attainment was ≥99% for C. albicans wild-type (WT) isolates with 3 mg/kg and for wild-type isolates of the other species with 5 mg/kg. L-AMB was four- to eightfold less active against the included non-C. albicans species than C. albicans. A standard 3-mg/kg dose is pharmacodynamically sufficient for C. albicans whereas our data suggest that 5 mg/kg may be recommendable for the included non-C. albicans species.

Novel antifungal drugs are urgently needed to treat candidiasis caused by the emerging fungal multidrug-resistant pathogen Candida auris. In this study, the most cost-effective drug repurposing technology was adopted to identify an appropriate option among the 1615 clinically approved drugs with anti-C. auris activity. High-throughput virtual screening of 1,3-beta-glucanosyltransferase inhibitors was conducted, followed by an analysis of the stability of 1,3-beta-glucanosyltransferase drug complexes and 1,3-beta-glucanosyltransferase-dutasteride metabolite interactions and the confirmation of their activity in biofilm formation and planktonic growth. The analysis identified dutasteride, a drug with no prior antifungal indications, as a potential medication for anti-auris activity in seven clinical C. auris isolates from Saudi Arabian patients. Dutasteride was effective at inhibiting biofilm formation by C. auris while also causing a significant reduction in planktonic growth. Dutasteride treatment resulted in disruption of the cell membrane, the lysis of cells, and crushed surfaces on C. auris, and significant (p-value = 0.0057) shrinkage in the length of C. auris was noted at 100,000×. In conclusion, the use of repurposed dutasteride with anti-C. auris potential can enable rapid recovery in patients with difficult-to-treat candidiasis caused by C. auris and reduce the transmission of nosocomial infection.

Currently, the spread of fungal infections is becoming an urgent problem. Fungi of the Candida genus are opportunistic microorganisms that cause superficial and life-threatening systemic candidiasis in immunocompromised patients. The list of antifungal drugs for the treatment of candidiasis is very limited, while the prevalence of resistant strains is growing rapidly. Therefore, the search for new antimycotics, including those exhibiting immunomodulatory properties, is of great importance. Plenty of natural compounds with antifungal activities may be extremely useful in solving this problem. This review evaluates the features of natural antimicrobial peptides, namely plant defensins as possible prototypes of new anticandidal agents. Plant defensins are important components of the innate immune system, which provides the first line of defense against pathogens. The introduction presents a brief summary regarding pathogenic Candida species, the pathogenesis of candidiasis, and the mechanisms of antimycotic resistance. Then, the structural features of plant defensins, their anticandidal activities, their mechanisms of action on yeast-like fungi, their ability to prevent adhesion and biofilm formation, and their combined action with conventional antimycotics are described. The possible mechanisms of fungal resistance to plant defensins, their cytotoxic activity, and their effectiveness in in vivo experiments are also discussed. In addition, for the first time for plant defensins, knowledge about their immunomodulatory effects is also presented.

Infection caused by the Humicola sp is extremely rare. We report the first case of fungal keratitis caused by Humicola pulvericola (H. pulvericola) in a 63-year-old man with a history of exposed to hot oil two weeks ago who developed keratitis. Direct examination of confocal microscopy and corneal scrapings showed fungal hyphae and isolates were identified by morphology and by sequencing the internal transcribed spacer region of ribosomal DNA. The in vitro antifungal susceptibilities of the case strain were tested for five antifungal agents. The results showed that the infectious agent was resistant towards fluconazole, caspofungin and amphotericin B; itraconazole and voriconazole were highly effective against H. pulvericola. He was diagnosed with H. pulvericola keratitis and treated with oral itraconazole and natamycin eyedrops. After one month of treatment, the lesion gradually improved, with the best-corrected visual acuity improving to 0.8.

A male patient in his 60s, with a history of tobacco use, presented with fever, weight loss, and cough, and was ultimately diagnosed with histoplasmosis. Initial treatment with itraconazole (ITZ) led to symptom improvement. However, two months later, he returned with lower extremity swelling and dyspnea. Imaging showed pleural effusions and reduced ejection fraction, suggesting itraconazole-induced cardiac toxicity. Transition to voriconazole and initiation of guideline-directed medical therapy improved symptoms. This case report delves into the cardiac side effects of itraconazole, notably heart failure, and elucidates the potential underlying mechanisms. Our goal is to emphasize the importance of monitoring patients on itraconazole for potential cardiac complications, necessitating timely intervention to mitigate adverse outcomes.