Search Results (224)

Background/Objectives: Galleria mellonella (G. mellonella) larvae have emerged as a valuable in vivo model for antifungal drug screening. This study aimed to determine the optimal inoculum concentrations of Candida albicans (C. albicans) in G. mellonella, as well as the appropriate fluconazole concentrations, in order to standardize a preliminary screening method for compounds with antifungal activity. Methods: Larvae were infected with four C. albicans strains, including two reference strains (ATCC^® 10231 and ATCC^® 90028) and two oral isolates (A1 and A2). Fluconazole toxicity was evaluated at doses of 20, 40, and 80 mg/kg over a 72 h period. In the treatment assays, larvae were infected via the left pro-leg and treated with fluconazole, administered as a single or two doses, one hour after infection. Larval viability was monitored over five days based on movement, cocoon formation, and melanization, and survival data were analyzed using Kaplan–Meier curves and the log-rank test. Results: Fluconazole showed no toxicity at the tested concentrations. Infection with up to 2 × 10⁷ cells/mL was non-lethal for most strains, except for A2, which exhibited 50% mortality within 48 h but it was effectively controlled with a single 20 mg/kg dose of fluconazole. Infection with 2 × 10⁸ cells/mL resulted in complete mortality within 48 h; however, a single 80 mg/kg dose significantly improved survival. Conclusions: The G. mellonella model proved to be a suitable and reproducible in vivo system for the preliminary screening of antifungal compounds. The standardized experimental conditions established in this study support its applicability for evaluating antifungal activity in early research stages. Future studies should expand this approach to different fungal species and antifungal agents, as well as explore its applicability in combination therapies. Full article

Bovine mastitis is a major bioeconomic and animal health challenge in dairy systems and is traditionally managed with intensive antibiotic therapy, contributing to antimicrobial resistance (AMR). This study explored the therapeutic potential of essential oils (EOs) from two native species of the Valdivian temperate rainforest, Laureliopsis philippiana (Tepa; LP_EO) and Drimys winteri (Canelo; DW_EO), against priority mastitis pathogens. Gas Chromatography–Mass Spectrometry (GC–MS) was used to characterize EO composition, and in vitro antibacterial and antifungal activities were evaluated against clinical isolates of Staphylococcus aureus, Streptococcus uberis and the azole-resistant yeast Pichia kudriavzevii by disk diffusion and broth microdilution assays. Both EOs were dominated by monoterpenes; LP_EO was richer in oxygenated monoterpenes (eucalyptol, terpinen-4-ol), whereas DW_EO showed a pinene-rich profile (β-pinene, α-pinene). DW_EO produced significantly larger inhibition zones than LP_EO against S. aureus and P. kudriavzevii and exhibited lower MIC₅₀/MIC₉₀ values for S. aureus, S. uberis and P. kudriavzevii. Notably, DW_EO showed a higher inhibitory activity against P. kudriavzevii with a MIC₉₀ of 4 mg/mL. These findings support DW_EO as a high-potential dual-action phytotherapeutic candidate for developing formulations and complementary tools within sustainable bovine udder health and antimicrobial stewardship frameworks. Full article

Background: Hypericin is a natural photosensitizer with promising antifungal potential, but its uptake kinetics in Candida (C.) albicans are not well defined. Objective: To characterize the time-dependent uptake of hypericin by C. albicans in vitro using fluorescence microscopy and quantitative image analysis. Methods: C. albicans ATCC 90028 was standardized to 0.5 McFarland and incubated with hypericin dissolved in DMSO. Samples were illuminated with an LED system tuned near 550 nm and imaged using a CCD fluorescence microscope with emission recorded above ≈600 nm. Images were analyzed in ImageJ, using a control-based threshold and percentage area (the percentage of pixels above the threshold in the whole field) as a fluorescence measure. Time points were 1, 3, 5, 7, 10, 15, 20, 25, 30, 35, 40, and 45 min, plus a separate dark-only series at 35–45 min. Data from three experiments were evaluated by ANOVA. Results: Fluorescence increased rapidly and showed a nonlinear, biphasic profile under light, with local maxima around 5–7 and 15–30 min. Dark-only samples at 35–45 min had a lower %Area and lacked a clear biphasic pattern. Conclusions: Hypericin uptake by C. albicans is dynamic, nonlinear, and light-dependent. These kinetics should be considered when designing hypericin-based antifungal photodynamic therapy protocols. Full article

Among Candida species, several are major opportunistic fungal pathogens capable of causing a wide spectrum of infections, ranging from superficial mucosal conditions to severe systemic diseases. Their success as human pathogens is largely due to their ability to rapidly adapt to diverse host environments and develop resistance to antifungal agents. Experimental evolution provides a powerful framework for understanding these adaptive processes by observing evolutionary change in real-time. Although most studies rely on in vitro systems and a limited set of Candida species, there is strong evidence that genome plasticity, including aneuploidy, loss of heterozygosity, and copy number variation, plays a central role in driving rapid adaptation. Experimental evolution has also been applied to study the dynamics of antifungal resistance, particularly to azoles, although relatively fewer studies have explored resistance to echinocandins and polyenes. This review summarizes current knowledge on experimental evolution in pathogenic Candida species, with a focus on genome plasticity, adaptation to host-imposed stress, and particularly on the emergence of antifungal resistance. It also identifies critical research gaps, including the need for broader species coverage, investigation of underexplored antifungal classes, and evaluation of combined therapies. A deeper understanding of these dynamics is essential to improve antifungal strategies and counter the growing threat of drug-resistant Candida spp. infections. Full article

Nystatin is a polyene macrolide antibiotic with broad-spectrum antifungal activity and serves as a key therapeutic agent for superficial fungal infections. This review systematically elaborates on its multicomponent chemical nature, its mechanism of action targeting ergosterol, and highlights the potential adverse effects, such as cardiotoxicity, associated with impurities like RT6 (albonoursin). The fundamental analytical techniques for quality control are outlined. Furthermore, the clinical applications and combination therapy strategies of nystatin in treating oral diseases, vaginitis, and otitis externa are summarized in detail. Regarding biosynthesis, the assembly mechanism of nystatin A₁ via the type I polyketide synthase pathway and its subsequent modification processes are thoroughly discussed. Emphasis is placed on the latest advances and potential of gene-editing technologies, particularly CRISPR/Cas9, in the targeted knockout of genes responsible for toxic components and in optimizing production strains to enhance nystatin yield and purity. Finally, this review prospects the future development of nystatin towards improved safety and efficacy through structural optimization, innovative delivery systems, and synthetic biology strategies, aiming to provide a reference for its further research and clinical application. Full article

Subcutaneous mycoses are a heterogeneous group of chronic fungal infections, usually acquired through traumatic inoculation of environmental fungi and particularly severe in immunocompromised and critically ill patients. These infections involve pathogens with marked morphological and physiopathological diversity, resulting in significant diagnostic and therapeutic challenges. Conventional treatment relies on systemic antifungals such as amphotericin B, itraconazole, and other azoles; however, these therapies are often limited by poor tissue penetration, adverse effects, and prolonged treatment regimens, especially in vulnerable patient populations. In this context, nanodrugs have emerged as promising alternatives by improving solubility, stability, bioavailability, and targeted delivery to infection sites. This review conducted a comprehensive literature search in PubMed, SciELO, ScienceDirect, Web of Science, and Scopus, identifying 31 eligible studies that developed and evaluated antifungal nanosystems using in vitro, ex vivo, and/or in vivo models. Quantitative outcomes included minimum inhibitory concentration (MIC), colony-forming units (CFU), inhibition halo diameter, and survival assays. Overall, the evidence indicates that several nanosystems may overcome key pharmacological limitations of conventional antifungals and enhance therapeutic outcomes. Nevertheless, important translational challenges remain, including toxicity, long-term safety, scalability, and regulatory approval, which must be addressed before clinical implementation. Full article

Background and Clinical Significance: Cerebral candidiasis (Candida albicans meningoencephalitis) is a rare but severe central nervous system (CNS) infection, usually associated with neurosurgical procedures or indwelling devices. Diagnosis is challenging due to frequent negativity of cerebrospinal fluid (CSF) cultures, and mortality remains high despite antifungal therapy. Case Presentation: We describe a 64-year-old woman who underwent retrosigmoid resection of a left vestibular schwannoma. The early postoperative course was complicated by fever, neurological deterioration, and hydrocephalus requiring external CSF drainage. Multiple lumbar punctures revealed inflammatory CSF profiles but persistently negative cultures. One month post-surgery, intraoperative samples from mastoid repair material grew Candida albicans, prompting antifungal therapy. Despite treatment, the patient experienced fluctuating neurological status and required multiple external ventricular drains. Three months after surgery, she clinically deteriorated and died. Autopsy showed diffuse meningeal thickening and purulent exudates at the brain base and posterior fossa. Histopathology confirmed chronic lympho-histiocytic meningitis with necrotizing foci containing Candida albicans. Conclusions: This case underscores the diagnostic and therapeutic challenges of post-neurosurgical Candida CNS infections. Repeatedly negative CSF cultures delayed diagnosis, emphasizing the value of ancillary tests such as β-d-glucan and molecular assays. Even with antifungal therapy, prognosis is poor. Autopsy remains essential for uncovering fatal healthcare-associated fungal infections and informing clinical vigilance and medico-legal assessment. Full article

The increasing resistance of Candida tropicalis to conventional antifungal agents has necessitated the development of effective, biocompatible alternatives derived from natural sources. Garlic (Allium sativum), known for its potent antimicrobial activity, contains 33 bioactive sulfur compounds, some of them being allicin, ajoene, and diallyl sulfides, that exhibit strong antifungal effects. However, the clinical application of garlic extract in pharmaceutical formulations remains limited due to its chemical instability, rapid degradation, and limited bioavailability. This review highlights recent advancements in pharmaceutical processing and particle engineering approaches to enhance the stability, delivery, and therapeutic efficacy of garlic extract-based antifungal formulations. Key strategies such as nanoparticle encapsulation, nanoemulsification, advanced drying techniques, and hydrogel-based delivery systems are discussed as effective approaches to enhance the stability and antifungal performance of garlic extract formulations. Special attention is given to hydrogel-based systems due to their excellent mucoadhesive properties, ease of application, and sustained release potential, making them ideal for treating localized C. tropicalis infections. The review also discusses formulation challenges and in vitro evaluation parameters, including minimum inhibitory concentration, minimum fungicidal concentration, and biofilm inhibition. By analyzing recent findings and technological trends, this review underscores the potential of garlic extract-based particle-engineered systems as sustainable and effective antifungal therapies. The scope of this review includes an in-depth evaluation of garlic extract-derived formulations, the application of particle processing technologies, and their translational potential in the design of next-generation antifungal delivery systems for managing C. tropicalis infections. Full article

Cutaneous infections caused by dematiaceous fungi are rare in the general population but are increasingly recognized in solid organ transplant recipients as a consequence of prolonged immunosuppression. When Alternaria species are confirmed as the causative agents of a skin infection, the condition is referred to as alternariosis. These infections may clinically resemble bacterial or neoplastic lesions and require accurate diagnosis and individualized therapy. We report one case of cutaneous alternariosis in a kidney transplant recipient receiving tacrolimus-based immunosuppression. The patient was a 47-year-old woman who sustained minor trauma to her knee three months after transplantation. She developed an ulcerated, crusted lesion, which coincided with severe neutropenia. Histology, culture and molecular identification confirmed A. infectoria. Treatment included systemic azole therapy (voriconazole followed by isavuconazole) and surgical excision, resulting in resolution without recurrence. This case highlights the importance of early recognition of alternariosis in transplant recipients. Successful management typically requires combined surgical and systemic antifungal therapy, with careful monitoring of drug interactions and immunosuppressive levels to prevent toxicity or rejection. Full article

Background/Objectives: Mucormycosis is a rapidly progressive invasive fungal infection that commonly involves the sinonasal region and skull base in patients with systemic comorbidities, yet robust ENT data from middle-income settings are scarce. Methods: We performed a single-center retrospective review of all patients with histopathologically confirmed mucormycosis treated in the Otorhinolaryngology Department of Dicle University between 2010 and 2023, covering a 14-year period. Eligible patients had paranasal sinus computed tomography at presentation and received surgical and/or systemic antifungal therapy. Demographic data, comorbidities, disease subtype, radiological extent, treatment modality and survival were extracted from records. Survival was estimated using Kaplan–Meier analysis, and group differences were tested with chi-square statistics (p ≤ 0.05). Results: Fifty-two patients met the inclusion criteria (mean age 56.5 ± 15.2 years; 57.7% male); 73.1% had at least one systemic comorbidity, most frequently diabetes mellitus (65.4%) and hematological malignancy (19.2%). Disease was sinonasal in 42.3%, rhino-orbital in 28.8% and rhino-orbito-cerebral in 28.8%. Baseline CT showed intracranial extension in 26.9%. Overall survival was 59.6% and differed markedly by subtype, highest in isolated sinonasal disease (81.8%) and lowest in rhino-orbito-cerebral disease (26.7%). Intracranial extension was associated with higher mortality (71.4% vs. 28.9%). Combined surgical debridement plus systemic antifungal therapy, used in 84.6% of patients, yielded lower mortality than antifungal therapy alone (31.8% vs. 87.5%). Conclusions: In this ENT cohort, prognosis was mainly determined by anatomical extent and treatment strategy. Our findings suggest that timely combined surgical and antifungal management, when feasible and in appropriately selected patients, is associated with improved survival outcomes. Full article

Invasive Mucormycosis (IM) is an extremely rare infection with a high mortality rate, caused by a group of fungi classified as Mucorales moulds. Rhizomucor pusillus is a saprophitic, thermophilic, and angioinvasive microorganism that grows and lives at about 45 °C and is usually found in different environmental spaces such as soil, air, water, food, and other organic matter. These features predispose the infection to wide dissemination, especially in immunocompromised patients and most often in children after chemotherapy for hematological malignancies (HMs). Mucormycosis in patients with hematologic malignancies and neutropenia represents between 0.07% and 4.29% of the concomitant diseases. IM can develop into an infection in different sites, but its most common manifestation is pulmonary, followed by rhino-orbital–cerebral and disseminated forms. In recent years, an increased morbidity rate has been associated with the ongoing COVID-19 pandemic, as cited in the literature. There are many publications with COVID-19-associated mucormycosis (CAM) cases. The present treatment protocol includes extensive and radical surgical debridement and systemic antifungal therapy with Liposomal Amphotericin B (L-AmB), Posaconazole, and Isavuconazole, either combined or as monotherapy. Despite these new treatment modalities, the mortality rate remains over 50%. We present a rare case of a 3-year-old child with acute lymphoblastic leukemia (ALL) and systemic Rhizomucor pusillus infection, diagnosed on the occasion of lung and brain abscesses. The patient underwent lung and brain surgery and is recovering well with no further complications. The two-year follow-up period shows no signs of recurrence of the disease. Full article

Disorders in the oral cavity caused by pathogenic fungi pose a significant clinical challenge, particularly in immunocompromised patients, as well as those undergoing oncological therapy or antibiotic treatment. A practical therapeutic approach involves the topical application of mucoadhesive drug dosage forms. However, only a limited number of such preparations are available on the pharmaceutical market. Mucoadhesive systems are especially advantageous, as they ensure prolonged retention and adequate concentrations of the active substances at the site of infection. Localized drug delivery enhances therapeutic efficacy compared to systemic administration, enabling lower drug doses, and consequently reducing the risk of side effects. Moreover, many fungal conditions require long-term treatment, which may be optimized by the use of mucoadhesive systems, improving patient compliance. Considering the issue of limited adhesion of conventional drug dosage forms and the moist environment in the oral cavity, providing optimal mucoadhesive properties is a key aspect. This article presents a comprehensive overview of the significance of treating oral candidiasis using mucoadhesive drug dosage forms, the mechanisms and advantages of mucoadhesion (including relevant polymers), and, most importantly, recent scientific reports on the development and quality assessment of mucoadhesive drug delivery systems for the management of oral fungal diseases. Full article

Background: Onychomycosis is a common nail infection primarily caused by Trichophyton rubrum, posing therapeutic challenges due to poor antifungal penetration and high recurrence rates. Conventional treatments include topical and systemic antifungals, but novel approaches such as laser therapy and chemical agents like nitric acid have emerged as promising alternatives or adjuncts. However, comparative evidence regarding the clinical and mycological efficacy of these treatments remains limited. Objectives: We aimed to assess and compare the clinical and mycological efficacy of three therapeutic modalities—69% nitric acid, 1064 nm Nd:YAG laser, and their combination—in the treatment of Trichophyton rubrum onychomycosis over a 12-month follow-up period. Methods: A prospective, comparative, observational study was conducted, assigning patients with confirmed onychomycosis to one of three treatment groups: nitric acid, Nd:YAG 1064 nm laser, or combination therapy. Clinical and mycological cure rates, mean time to clinical resolution, changes in Onychomycosis Severity Index [OSI] scores, and mycological relapse rates were assessed over a 12-month follow-up. Results: All three groups demonstrated significant improvement in both clinical and mycological cure rates, with the combination therapy yielding the most favorable outcomes in terms of response speed and durability. Laser and nitric acid monotherapies were also effective, though associated with lower cure rates and longer times to resolution. The relapse rate was lowest in the combination group. Conclusions: The combination of nitric acid and Nd:YAG laser appears to be a more effective therapeutic option for Trichophyton rubrum onychomycosis, offering superior clinical and mycological outcomes compared to monotherapies, with faster resolution and lower relapse rates. These findings suggest that combination therapy may optimize the management of this challenging nail infection. Full article

Candida biofilms play a critical role in clinical settings, contributing to persistent and device-associated infections and conferring resistance to antifungal agents, particularly in immunocompromised or hospitalized patients. Biofilm formation varies among Candida species, including C. albicans and non-albicans species, such as C. glabrata, C. tropicalis, C. parapsilosis, and C. auris, due to species-specific transcriptional networks that regulate modes of biofilm development, extracellular matrix composition, and metabolic reprogramming. These differences influence biofilm responses to treatment and the severity of infections, which can be further complicated in polymicrobial biofilms that modulate colonization and virulence. Understanding the mechanisms driving biofilm formation and interspecies interactions is essential for developing effective therapies and requires appropriate experimental models. Available models range from simplified in vitro systems to more complex ex vivo and in vivo approaches. Static in vitro models remain widely used due to their simplicity and reproducibility, but they poorly mimic physiological conditions and require careful standardization. Ex vivo tissue models offer a balance between practicality and biological relevance, enabling the study of biofilm physiology, host–microbe interactions and immune responses. In vivo models, primarily in mice, remain the gold standard for testing antifungal therapies, while alternative systems such as Galleria mellonella larvae provide simpler, cost-effective approaches. Advanced in vitro platforms, including organ-on-chip systems, bridge the gap between simplified tests and physiological relevance by simulating fluid dynamics, tissue architecture, and immune complexity. This review aims to examine Candida biofilms across species, highlighting differences in structural diversity and clinical implications, and to provide a guide to the most widely used experimental models supporting studies on Candida biofilm biology for the development of new therapeutic targets or drug testing. Full article

Central nervous system (CNS) cryptococcosis caused by Cryptococcus neoformans is a severe opportunistic infection that primarily affects individuals with impaired cellular immunity. Although the classic presentation includes headache, fever, and meningeal signs, chronically immunosuppressed patients may develop atypical neuropsychiatric manifestations, leading to diagnostic delays. We report the case of a 53-year-old man with rheumatoid arthritis (RA) receiving long-term prednisolone and etanercept therapy, who presented with a 7-day history of depressive mood, anhedonia, social withdrawal, irritability, and progressive confusion. Neurological examination revealed disorientation without focal deficits. Brain imaging showed only mild cortical atrophy, and cerebrospinal fluid (CSF) analysis revealed lymphocytic pleocytosis, low glucose, and elevated protein levels. Multiplex PCR (FilmArray^®) of CSF identified Cryptococcus neoformans, CSF positive to C. neoformans. The patient was treated with liposomal amphotericin B followed by fluconazole, resulting in gradual improvement of both neurological and psychiatric symptoms. This case highlights an unusual presentation of CNS cryptococcosis in a non-HIV immunosuppressed patient with RA, emphasizing that acute psychiatric or cognitive changes can be the predominant manifestation. Clinicians should consider fungal infections in the differential diagnosis of acute neuropsychiatric symptoms in patients receiving chronic corticosteroid and biologic therapy. Early recognition and molecular diagnosis can facilitate timely antifungal treatment, potentially improving prognosis and reducing morbidity associated with delayed therapy. This report underscores the importance of awareness of atypical presentations of opportunistic infections in immunosuppressed populations. Full article