Search Results (78)

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

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

Infections with strains of the Cryptococcus neoformans species complex are responsible for over 100,000 deaths per year, predominantly due to meningitis in immunocompromised individuals. Despite much research, there are no licensed fungal vaccines available. Most experimental cryptococcal vaccine formulations have been tested in preclinical models using laboratory strains of C. neoformans, particularly H99 and KN99. However, to be effective, vaccines need to protect against the wide variety of cryptococcal isolates found worldwide, particularly in regions that have the highest burden of infections. Therefore, we explored vaccine-mediated protection of BALB/c mice against experimental cryptococcosis due to six C. neoformans strains originally isolated from patients with cryptococcal meningitis in Vietnam, Uganda, and Botswana. Two vaccines were tested: a live-attenuated C. neoformans vaccine lacking three chitin deacetylase genes, and a quadrivalent subunit protein vaccine adjuvanted with Cationic Adjuvant Formulation 01. When compared to unvaccinated mice, both vaccines provided significant protection against all six clinical strains. However, the degree of protection varied as a function of vaccine formulation and clinical strain. Lung leukocytes from vaccinated and infected mice had significantly increased antigen-stimulated interferon-gamma production compared with infected but unvaccinated mice. Thus, although the degree of protection varied, two cryptococcal vaccines significantly protected mice against experimental infection with cryptococcal strains representative of regions of the world that account for the majority of cryptococcal meningitis cases found globally. These data provide preclinical support for trialing vaccines in persons at high risk for developing cryptococcosis. Full article

Cryptococcus neoformans is a fungal pathogen commonly found in the environment. It mainly infects immunocompromised individuals, causing cryptococcal pneumonia and meningitis, which result in hundreds of thousands of deaths each year. Zinc finger proteins, with zinc finger domains, are common across organisms and serve many biological functions. In this study, we identified and characterized Zfp2, a C₃HC₄-type zinc finger protein, which regulates cell fusion and virulence in C. neoformans. Stress tests showed that the zfp2Δ mutant is hypersensitive to SDS, Congo red, NaCl, KCl, caspofungin, and fluconazole, suggesting that Zfp2 helps maintain cell membrane or wall integrity in C. neoformans. Notably, deleting ZFP2 reduced capsule size, while its overexpression led to capsule enlargement. The zfp2Δ mutants also demonstrated a growth defect at 37 °C. Cell fusion assay showed that Zfp2 is essential for cell fusion during sexual reproduction, as zfp2Δ mutants could not fuse during bilateral mating. To understand why the zfp2Δ mutants failed to fuse, we examined key genes in the pheromone response pathway and found that Zfp2 may affect cell fusion by regulating this pathway. Finally, a virulence test in mice showed that both ZFP2 deletion and overexpression significantly reduced C. neoformans’ virulence. Overall, our research suggests that the zinc finger protein Zfp2 is vital for cell fusion and virulence in C. neoformans. Full article

Sertraline, a selective serotonin reuptake inhibitor (SSRI), has emerged as a candidate for therapeutic repurposing due to its reported antifungal activity. We systematically reviewed in vitro, in vivo, and clinical evidence up to July 2025 (PubMed, Scopus, Web of Science). As a result, 322 records were screened and 63 studies were found to meet the inclusion criteria (PRISMA 2020). We close a critical gap by consolidating relevant evidence on Candida auris, including preclinical in vivo models, which have been under-represented in previous summaries. Outcomes included minimum inhibitory and fungicidal concentrations (MIC/MFC), biofilm inhibition, fungal burden, survival, and pharmacokinetic/pharmacodynamic parameters. Preclinical data indicate its activity against clinically relevant fungi—particularly Cryptococcus neoformans and Candida spp., including C. auris—as well as consistent anti-biofilm effects and synergy with amphotericin B, fluconazole, micafungin, or voriconazole. Mechanistic evidence implicates mitochondrial dysfunction, membrane perturbation, impaired protein synthesis, and calcium homeostasis disruption. However, its potential for clinical translation remains uncertain: in cryptococcal meningitis, small phase II studies suggested improved early fungicidal activity, whereas a phase III randomized trial did not demonstrate a benefit regarding survival. Pharmacokinetic constraints at conventional doses, the absence of an intravenous formulation, and safety considerations at higher doses further limit its immediate applicability. Overall, the available evidence supports sertraline as a promising adjuvant candidate, rather than a stand-alone antifungal. Future research should define PK/PD targets, optimize doses and formulations, and evaluate rational combinations through rigorously designed trials, particularly for multidrug-resistant and biofilm-associated infections. Full article

Coccidioidal meningitis (CM) is a rare but life-threatening complication of disseminated coccidioidomycosis, occurring in ~16% of cases, particularly among children in endemic regions such as the southwestern US and northern Mexico. Without timely diagnosis and antifungal therapy, pediatric CM is almost universally fatal within the first year. Hydrocephalus develops in up to 50% of cases. In 2000, Galgiani et al. established fluconazole as first-line therapy for CM. Subsequent guidelines refined management but did not specifically address pediatric patients (>1 month–≤19 years). No studies in the fluconazole era have systematically evaluated risk factors for complications in this population. We therefore conducted a systematic review and proportional synthesis of pediatric CM cases, focusing on CNS complications and outcomes. PubMed/MEDLINE, Embase (Ovid), and Web of Science were systematically searched (2000–2025). PROSPERO registration ID (1130290). Inclusion criteria encompassed epidemiological studies, case series, and case reports that described at least one pediatric case of CM or CNS involvement, confirmed by diagnostic methods. Cases in adults, neonates (<1 month), congenital infections, teratogenicity studies, reviews, or incomplete reports were excluded. Only cases with complete individual data (n = 48) were included. Methodological rigor was ensured using JBI Critical Appraisal Tools. Of 1089 studies, 31 met the inclusion criteria, representing 3874 pediatric cases. CM/CNS involvement was confirmed in 165 cases (4.25%; 95% CI: 3.6–4.9%), with hydrocephalus in 62 (37.5%). Among 48 case reports with complete data, fluconazole was first-line therapy in 65%. Serum CF titers ≥ 1:16 were associated with hydrocephalus plus stroke (p = 0.027) and independently predicted adverse outcomes (relapse/death; OR = 4.5, p = 0.037), whereas lifelong azole therapy was associated with improved outcomes (overall survival mean, 82 vs. 32 months; p = 0.002). Pediatric CM remains highly lethal, with hydrocephalus a frequent and severe complication. High serum CF titers (≥1:16) predict poor outcomes, emphasizing the urgent need for standardized, pediatric-specific diagnosis and management guidelines. Full article

A 47-year-old woman presented with a two-year history of progressive visual symptoms and headaches. Lumbar puncture revealed lymphocytic pleocytosis, elevated protein, low glucose, and a CSF CrAg titer of 1:256. She was treated empirically for cryptococcal meningitis with amphotericin B, flucytosine, and fluconazole for 15 months. Her symptoms persisted, and repeated CSF and serum CrAg, fungal cultures, and an extensive infectious workup were negative. CSF flow cytometry eventually demonstrated a monoclonal B-cell population suggestive of a lymphoproliferative process. Imaging, including MRI and PET scans, did not reveal systemic disease. A ventriculoperitoneal (VP) shunt was placed for symptom management. This case emphasizes the limitations of CrAg testing and the potential for false positives. It underscores the need for integrating clinical, laboratory, and imaging data when evaluating chronic meningitis. Full article

Background/Objectives: Opportunistic fungal infections are common among people living with HIV (PLHIV) and contribute substantially to morbidity, mortality, and hospitalization rates in this population. This study aimed to determine the prevalence of dermatological manifestations of fungal infections in HIV-positive patients and examine their association with demographic, clinical, and immunological characteristics. Methods: A retrospective review of medical records from 2500 PLHIV treated at the Infectious Diseases Unit of “Andreas Syggros” Hospital for Skin and Venereal Diseases between 1988 and 2017. Data from patients diagnosed with opportunistic fungal infections were analyzed. Participants were classified as either antiretroviral therapy (ART)-naïve or already receiving treatment. Recorded fungal infections were correlated with epidemiological variables and CD4+ T-cell counts. Results: Opportunistic fungal infections were identified in 859 patients (34.36%), with a marked male predominance. Candidiasis was the most frequently reported condition, with a higher prevalence among female patients. Lower CD4+ counts were significantly associated with an increased risk of cryptococcal meningitis, esophageal candidiasis, Pneumocystis jirovecii pneumonia (PJP), and oral candidiasis, whereas higher CD4+ counts were more common in patients with dermatophytosis, onychomycosis, and pityriasis/tinea versicolor. Conclusions: Opportunistic fungal infections remain highly prevalent in PLHIV, particularly among those with advanced immunosuppression. CD4+ T-cell counts are key diagnostic and prognostic markers, reinforcing their importance in monitoring disease progression and guiding clinical management. Full article

With the rise in immunocompromised individuals and patients with immune-related comorbidities such as COVID-19, the rate of fungal infections is growing. This increase, along with the current plateau in antifungal drug development, has made understanding the pathogenesis and dissemination of these organisms more pertinent than ever. The mouse model of fungal infection, while informative on a basic scientific level, has severe limitations in terms of translation to the human disease. Here we present data supporting the implementation of the human cerebral organoid model, which is generated from human embryonic stem cells and accurately recapitulates relevant brain cell types and structures, to study fungal infection and dissemination to the central nervous system (CNS). This approach provides direct insight into the relevant pathogenesis of specific fungal organisms in human tissues where in vivo models are impossible. With this model system we assessed the specific brain tropisms and cellular effects of fungal pathogens known to cross the blood–brain barrier (BBB), such as Cryptococcus neoformans. We determined the effects of this fungal pathogen on the overall gross morphology, cellular architecture, and cytokine release from these model organoids. Furthermore, we demonstrated that C. neoformans penetrates and invades the organoid tissue and remains present throughout the course of infection. These results demonstrate the utility of this new model to the field and highlight the potential for this system to elucidate fungal pathogenesis to develop new therapeutic strategies to prevent and treat the disseminated stages of fungal diseases such as cryptococcal meningitis. Full article

Cryptococcus neoformans is an opportunistic fungal pathogen and causative agent of cryptococcosis and cryptococcal meningitis (CM). Cryptococcal disease accounts for up to 19% of AIDS-related mortalities globally, warranting its label as a pathogen of critical priority by the World Health Organization. Standard treatments for CM rely heavily on high doses of antifungal agents for long periods of time, contributing to the growing issue of antifungal resistance. Moreover, mortality rates for CM are still incredibly high (13–78%). Attempts to create new and effective treatments have been slow due to the complex and diverse set of immune-evasive and survival-enhancing virulence factors that C. neoformans employs. To bolster the development of better clinical tools, deeper study into host–Cryptococcus proteomes is needed to identify clinically relevant proteins, pathways, antigens, and beneficial host response mechanisms. Mass spectrometry-based proteomics approaches serve as invaluable tools for investigating these complex questions. Here, we discuss some of the insights into cryptococcal disease and biology learned using proteomics, including target proteins and pathways regulating Cryptococcus virulence factors, metabolism, and host defense responses. By utilizing proteomics to probe deeper into these protein interaction networks, new clinical tools for detecting, diagnosing, and treating C. neoformans can be developed. Full article

Cryptococcosis, an opportunistic fungal infection predominantly caused by Cryptococcus neoformans, is the third most common invasive fungal disease in solid organ transplant recipients. While well-characterized in adult kidney transplant (KT) patients, pediatric data remain sparse. This article compares clinical presentation, immune response, renal involvement, and management strategies of cryptococcosis between adult and pediatric KT recipients. In adults, the disease typically presents as cryptococcal meningitis or pulmonary infection, often complicated by delayed diagnosis and high mortality. In contrast, children frequently exhibit non-specific respiratory symptoms or disseminated disease, reflecting immune immaturity and increased susceptibility to hematogenous spread. Key immunopathological differences include impaired Th1 type responses, macrophage dysfunction, and variable complement activity across age groups. Management involves similar antifungal regimens such as liposomal amphotericin B, flucytosine, and fluconazole, but requires weight-based dosing and careful toxicity monitoring in pediatric patients. Early diagnosis through serum cryptococcal antigen screening, appropriate adjustment of immunosuppressive therapy, and coordinated multidisciplinary care are essential. The findings underscore the need for pediatric specific research and clinical vigilance, emphasizing tailored antifungal dosing and individualized immune management to improve outcomes in this vulnerable population. Full article

Meningitis is an inflammation of the meninges that can sometimes be a life-threatening disease. Therefore, fast and proper diagnosis with the implementation of adequate treatment is crucial in its management. Treatment depends on etiology, which can be viral, bacterial, fungal, and parasitic. Diagnosis is based on thorough clinical examination with a performance of lumbar puncture in the case of meningitis suspicion. This procedure, however, remains invasive with several contraindications and a need for a patient’s consent, which is not always given due to the patient’s fear of it, for instance. Thus, this systematic review aimed to summarize the available literature on the topic of blood biomarkers in meningitis differentiation. A selection process was performed by two authors independently in accordance with the Preferred Research Items for Systematic Reviews and Meta-analyses. Two databases were screened. It led to the identification of 863 articles, of which 43 were eventually included in the systematic review. The analysis resulted in identifying blood biomarkers in both adult and pediatric meningitis. Most studies focused on inflammatory markers, such as C-reactive protein and procalcitonin, from which procalcitonin showed better utility. Among other analyzed molecules were, for instance, interleukins, apolipoproteins, and microRNAs. Moreover, many researchers suggested that combining biomarkers or implementing novel technologies may lead to the best accuracy. However, many suggested methods lack validation, which stands in the way of making them widely used. Full article

Cryptococcus neoformans is a globally distributed human fungal pathogen that can cause cryptococcal meningitis with high morbidity and mortality. In this study, we identified an anaphase-promoting complex (APC) activator, Cdh1, and examined its impact on the virulence of C. neoformans. Our subcellular localization analysis revealed that Cdh1 is situated in the nucleus of C. neoformans. Disrupting or overexpressing the CDH1 gene caused abnormal capsule formation in C. neoformans. The cdh1Δ mutant displayed slight sensitivity when grown at 37 °C, indicating that Cdh1 plays a role in maintaining the growth of C. neoformans at 37 °C. A fungal virulence assay showed that Cdh1 is closely associated with the virulence of C. neoformans, and both the cdh1Δ mutant and CDH1^OE overexpression strains significantly diminished the virulence of C. neoformans. The Cryptococcus–macrophage interaction assay revealed that both the cdh1∆ mutant and the CDH1^OE strains had significantly lower proliferation ability inside macrophages. Furthermore, the infection of the cdh1Δ mutant significantly activated neutrophil recruitment, as well as Th2 and Th17 immune responses, in lung tissue. In summary, our findings indicate that Cdh1 is crucial for producing virulence factors and fungal virulence in C. neoformans. The findings of this study can offer valuable insights and form the basis for further study of the regulatory mechanisms governing the pathogenicity of C. neoformans, potentially leading to the development of novel therapeutic strategies. Full article

Evaluating altered mental status and suspected meningeal disorders in children often begins with imaging, typically before a lumbar puncture. The challenge is that meningeal enhancement is a common finding across a range of pathologies, making diagnosis complex. This review proposes a categorization of meningeal diseases based on their predominant imaging characteristics. It includes a detailed description of the clinical and imaging features of various conditions that lead to leptomeningeal or pachymeningeal enhancement in children and adolescents. These conditions encompass infectious meningitis (viral, bacterial, tuberculous, algal, and fungal), autoimmune diseases (such as anti-MOG demyelination, neurosarcoidosis, Guillain-Barré syndrome, idiopathic hypertrophic pachymeningitis, and NMDA-related encephalitis), primary and secondary tumors (including diffuse glioneuronal tumor of childhood, primary CNS rhabdomyosarcoma, primary CNS tumoral metastasis, extracranial tumor metastasis, and lymphoma), tumor-like diseases (Langerhans cell histiocytosis and ALK-positive histiocytosis), vascular causes (such as pial angiomatosis, ANCA-related vasculitis, and Moyamoya disease), and other disorders like spontaneous intracranial hypotension and posterior reversible encephalopathy syndrome. Despite the nonspecific nature of imaging findings associated with meningeal lesions, narrowing down the differential diagnoses is crucial, as each condition requires a tailored and specific treatment approach. Full article

Cryptococcus neoformans is a widespread fungal pathogen that can infect the human central nervous system (CNS) and cause fungal meningitis, leading to hundreds of thousands of deaths worldwide each year. Previous studies have demonstrated that many signal transduction pathways are crucial for the morphological development and virulence of C. neoformans. In this review, data from over 116 research articles have been compiled to show that many signaling pathways control various characteristics of C. neoformans, individually or in association with other pathways, and to establish strong links among them to better understand C. neoformans pathogenesis. Every characteristic of C. neoformans is closely linked to these signaling pathways, making this a rich area for further research. It is essential to thoroughly explore these pathways to address questions that remain and apply a molecular mechanistic approach to link them. Targeting these pathways is crucial for understanding the exact mechanism of infection pathogenesis and will facilitate the development of antifungal drugs as well as the diagnosis and prevention of cryptococcosis. Full article