Candida Tropicalis Endocarditis: A case report and literature review.

Fungi rarely cause infective endocarditis but when they do, they are often associated with poor outcomes. Candida tropicalis accounts for only 10% of Candida endocarditis cases. A case of a 30-year-old male with a history of intravenous drug abuse was reported to the emergency department in August, 2021 with right-sided leg pain and fever for 3 days. A trans-thoracic echocardiogram showed a vegetation on the aortic valve and a computed tomography angiogram showed complete nonopacification of the right-sided common iliac artery and the superficial femoral artery just distal to its branching of the right profunda femoris artery. An emergent right iliofemoral embolectomy was done. Candida tropicalis was isolated from tissue and blood cultures. The patient was successfully treated with aortic valve replacement and intravenous caspofungin. The other reported cases of Candida tropicalis were reviewed and findings were compared with those reported in patients with Candida albicans and Candida parapsilosis endocarditis.

A synthetic peptide mimic kills Candida albicans and synergistically prevents infection.

More than two million people worldwide are affected by life-threatening, invasive fungal infections annually. Candida species are the most common cause of nosocomial, invasive fungal infections and are associated with mortality rates above 40%. Despite the increasing incidence of drug-resistance, the development of novel antifungal formulations has been limited. Here we investigate the antifungal mode of action and therapeutic potential of positively charged, synthetic peptide mimics to combat Candida albicans infections. Our data indicates that these synthetic polymers cause endoplasmic reticulum stress and affect protein glycosylation, a mode of action distinct from currently approved antifungal drugs. The most promising polymer composition damaged the mannan layer of the cell wall, with additional membrane-disrupting activity. The synergistic combination of the polymer with caspofungin prevented infection of human epithelial cells in vitro, improved fungal clearance by human macrophages, and significantly increased host survival in a Galleria mellonella model of systemic candidiasis. Additionally, prolonged exposure of C. albicans to the synergistic combination of polymer and caspofungin did not lead to the evolution of tolerant strains in vitro. Together, this work highlights the enormous potential of these synthetic peptide mimics to be used as novel antifungal formulations as well as adjunctive antifungal therapy.

Antifungal susceptibility pattern of Candida auris strains: Analysis of clinical strains in a tertiary-care educational university hospital.

Herein, we aimed to investigate the antifungal susceptibility pattern of Candida auris clinical strains in our setting Bahrain Oncology Center-King Hamad University Hospital-Bahrain. C. auris strains isolated from different clinical specimens in the Microbiology Laboratory from October-2021 to November-2022 were evaluated. Species-level identification of fungi was performed by MALDI-TOF (Bruker, Germany). Minimum inhibitory concentration (MIC) was determined either by E-test strips or by MICRONAUT MIC system based on CDC guidelines for C. auris antifungal interpretation. Fluconazole, amphotericin-B, voriconazole, and caspofungin susceptibility data of the clinical strains were analyzed. A total of 40 clinical isolates were included: 25% were blood culture isolates, 65% were urinary, and 10% were soft tissue isolates. Only 29 strains could be tested for amphotericin-B and 32 for voriconazole. Overall resistance pattern was as follows: 100% resistance to fluconazole, 2.5% resistance to caspofungin, and 0% resistance to amphotericin b. Median voriconazole MIC was 0.015 ug/ml (min 0.08, max= 0.064 ug/ml). We had no fluconazole-sensitive strain and only one caspofungin-resistant strain. A single isolate (2.5%), which was associated with candidemia, demonstrated resistance to two antifungal agents: fluconazole and caspofungin. No triple or quadruple drug resistant strain existed.

Investigation of the influence of pH and temperature on melanization and survival under oxidative stress in Cryptococcus neoformans.

Cryptococcus neoformans is an opportunistic pathogenic fungus that produces melanin during infection, an important virulence factor in Cryptococcal infections that enhances the ability of the fungus to resist immune defense. This fungus can synthesize melanin from a variety of substrates, including L-DOPA (L-3,4-dihydroxyphenylalanine). Since melanin protects the fungus from various stress factors such as oxidative, nitrosative, extreme heat and cold stress; we investigated the effects of environmental conditions on melanin production and survival. In this study, we investigated the effects of different pH values (5.6, 7.0 and 8.5) and temperatures (30 °C and 37 °C) on melanization and cell survival using a microtiter plate-based melanin production assay and an oxidative stress assay, respectively. In addition, the efficacy of compounds known to inhibit laccase involved in melanin synthesis, i.e., tunicamycin, ß-mercaptoethanol, dithiothreitol, sodium azide and caspofungin on melanization was evaluated and their sensitivity to temperature and pH changes was measured. The results showed that melanin content correlated with pH and temperature changes and that pH 8.5 and 30 °C, were best for melanin production. Besides that, melanin production protects the fungal cells from oxidative stress induced by hydrogen peroxide. Thus, changes in pH and temperature drastically alter melanin production in C. neoformans and it correlates with the fungal survival. Due to the limited antifungal repertoire and the development of resistance in cryptococcal infections, the investigation of environmental conditions in the regulation of melanization and survival of C. neoformans could be useful for future research and clinical phasing.

Transcriptome Analysis of Human Dermal Cells Infected with Candida auris Identified Unique Pathogenesis/Defensive Mechanisms Particularly Ferroptosis.

Candida auris is an emerging multi-drug resistant yeast that can cause life-threatening infections. A recent report clarified the ability of C. auris to form a biofilm with enhanced drug resistance properties in the host skin's deep layers. The formed biofilm may initiate further bloodstream spread and immune escape. Therefore, we propose that secreted chemicals from the biofilm may facilitate fungal pathogenesis. In response to this interaction, the host skin may develop potential defensive mechanisms. Comparative transcriptomics was performed on the host dermal cells in response to indirect interaction with C. auris biofilm through Transwell inserts compared to planktonic cells. Furthermore, the effect of antifungals including caspofungin and fluconazole was studied. The obtained data showed that the dermal cells exhibited different transcriptional responses. Kyoto Encyclopedia of Genes and Genomes and Reactome analyses identified potential defensive responses employed by the dermal cells and potential toxicity induced by C. auris. Additionally, our data indicated that the dominating toxic effect was mediated by ferroptosis; which was validated by qRT-PCR, cytotoxicity assay, and flow cytometry. On the other hand, the viability of C. auris biofilm was enhanced and accompanied by upregulation of MDR1, and KRE6 upon interaction with dermal cells; both genes play significant roles in drug resistance and biofilm maturation, respectively. This study for the first-time shed light on the dominating defensive responses of human dermal cells, microbe colonization site, to C. auris biofilm and its toxic effects. Further, it demonstrates how C. auris biofilm responds to the defensive mechanisms developed by the human dermal cells.

Comparative efficacies of the three echinocandins for Candida auris candidemia: real world evidence from a tertiary centre in India.

Though echinocandins are the first line of therapy for C. auris candidemia, there is little clinical data to guide the choice of therapy within this class. This was the first study to compare the three echinocandins in terms of efficacy and outcomes for C. auris candidemia. This was a retrospective analysis of 82 episodes of candidemia caused by C. auris comparing outcomes across the three echinocandins. Majority patients in our study were treated with micafungin. Susceptibility rates were the lowest for caspofungin (35.36% resistance), with no resistance reported for the other two echinocandins. When a susceptible echinocandin was chosen, caspofungin resistance was not a factor significantly associated with mortality. Also, when a susceptible echinocandin was used for therapy, the choice within the class did not affect clinical cure, microbiological cure, or mortality (P > 0.05 for all). Failure to achieve microbiological cure (P = 0.018) and receipt of immune-modulatory therapy (P = 0.01) were significantly associated with increased mortality. Significant cost variation was noted among the echinocandins. Considering the significant cost variation, comparable efficacies can be reassuring for the prescribing physician.

This is the first study comparing efficacy of the three echinocandins in C. auris candidemia. The clinical efficacy of the three echinocandins was found to be comparable. Micafungin and anidulafungin had lower minimum inhibitory concentrations. A significant cost variation was noted.

Metagenomic next-generation sequencing could play a pivotal role in validating the diagnosis of invasive mold disease of the central nervous system.

Background: Invasive mold diseases of the central nervous (CNS IMD) system are exceedingly rare disorders, characterized by nonspecific clinical symptoms. This results in significant diagnostic challenges, often leading to delayed diagnosis and the risk of misdiagnosis for patients. Metagenomic Next-Generation Sequencing (mNGS) holds significant importance for the diagnosis of infectious diseases, especially in the rapid and accurate identification of rare and difficult-to-culture pathogens. Therefore, this study aims to explore the clinical characteristics of invasive mold disease of CNS IMD in children and assess the effectiveness of mNGS technology in diagnosing CNS IMD. Methods: Three pediatric patients diagnosed with Invasive mold disease brain abscess and treated in the Pediatric Intensive Care Unit (PICU) of the First Affiliated Hospital of Zhengzhou University from January 2020 to December 2023 were selected for this study. Results: Case 1, a 6-year-old girl, was admitted to the hospital with "acute liver failure." During her hospital stay, she developed fever, irritability, and seizures. CSF mNGS testing resulted in a negative outcome. Multiple brain abscesses were drained, and Aspergillus fumigatus was detected in pus culture and mNGS. The condition gradually improved after treatment with voriconazole combined with caspofungin. Case 2, a 3-year-old girl, was admitted with "acute B-lymphoblastic leukemia." During induction chemotherapy, she developed fever and seizures. Aspergillus fumigatus was detected in the intracranial abscess fluid by mNGS, and the condition gradually improved after treatment with voriconazole combined with caspofungin, followed by "right-sided brain abscess drainage surgery." Case 3, a 7-year-old girl, showed lethargy, fever, and right-sided limb weakness during the pending chemotherapy period for acute B-lymphoblastic leukemia. Rhizomucor miehei and Rhizomucor pusillus was detected in the cerebrospinal fluid by mNGS. The condition gradually improved after treatment with amphotericin B combined with posaconazole. After a six-month follow-up post-discharge, the three patients improved without residual neurological sequelae, and the primary diseases were in complete remission. Conclusion: The clinical manifestations of CNS IMD lack specificity. Early mNGS can assist in identifying the pathogen, providing a basis for definitive diagnosis. Combined surgical treatment when necessary can help improve prognosis.

Compare the efficacy of antifungal agents as primary therapy for invasive aspergillosis: a network meta-analysis.

BACKGROUND: Several antifungal agents are available for primary therapy in patients with invasive aspergillosis (IA). Although a few studies have compared the effectiveness of different antifungal agents in treating IA, there has yet to be a definitive agreement on the best choice. Herein, we perform a network meta-analysis comparing the efficacy of different antifungal agents in IA. METHODS: We searched PubMed, Embase, and the Cochrane Central Register of Controlled Clinical Trials databases to find studies (both randomized controlled trials [RCTs] and observational) that reported on treatment outcomes with antifungal agents for patients with IA. The study quality was assessed using the revised tool for risk of bias and the Newcastle Ottawa scale, respectively. We performed a network meta-analysis (NMA) to summarize the evidence on antifungal agents' efficacy (favourable response and mortality). RESULTS: We found 12 studies (2428 patients) investigating 11 antifungal agents in the primary therapy of IA. There were 5 RCTs and 7 observational studies. When treated with monotherapy, isavuconazole was associated with the best probability of favourable response (SUCRA, 77.9%; mean rank, 3.2) and the best reduction mortality against IA (SUCRA, 69.1%; mean rank, 4.1), followed by voriconazole and posaconazole. When treated with combination therapy, Liposomal amphotericin B plus caspofungin was the therapy associated with the best probability of favourable response (SUCRA, 84.1%; mean rank, 2.6) and the best reduction mortality (SUCRA, 88.2%; mean rank, 2.2) against IA. CONCLUSION: These findings suggest that isavuconazole, voriconazole, and posaconazole may be the best antifungal agents as the primary therapy for IA. Liposomal amphotericin B plus caspofungin could be an alternative option.

Investigation of antifungal susceptibility of Aspergillus species isolated from systemic clinical specimens by different methods.

PURPOSE: Due to the potential for Aspergillus species to cause lethal infections and the rising rates of antifungal resistance, the significance of antifungal susceptibility tests has increased. We aimed to assess the sensitivities of Aspergillus species to amphotericin B (AMB), voriconazole (VOR), itraconazole (ITZ), and caspofungin (CAS) using disk diffusion (DD) and gradient diffusion (GD) methods and compare them with broth microdilution (BMD) as the reference susceptibility method. METHODS: The study involved 62 Aspergillus fumigatus, 28 Aspergillus flavus, and 16 Aspergillus terreus isolates, totaling 106 Aspergillus isolates. BMD and DD methods were performed in accordance with CLSI M38-A2 and CLSI M51-A documents, respectively. The GD method utilized nonsupplemented Mueller Hinton agar (MHA) as the medium. RESULTS: In the BMD method, the lowest minimal inhibitory concentration (MIC)90 or minimal effective concentration (MEC)90 values were observed for VOR and CAS (0.5 µg/mL and 0.06 µg/mL, respectively). AMB and ITZ MIC90 values were both 2 µg/mL. In our comparison of the GD method with the BMD method at ±2 dilution, we observed essential agreement rates of 91.6%, 99.1%, 100%, and 38.6% for AMB, VOR, ITZ, and CAS, respectively. When comparing DD and BMD methods, we found categorical agreement rates of 65.1%, 99.1%, 77.3%, and 100% for AMB, VOR, ITZ, and CAS, respectively. For GD and BMD methods, these rates were 79.2%, 99.1%, 87.8%, and 100%. CONCLUSIONS: Given the high essential and categorical agreement rates, we posit that the GD method is a viable alternative to the BMD method for AMB, ITZ and VOR but not for CAS. In addition, the use of nonsupplemented MHA in the GD method proves advantageous due to its cost-effectiveness and widespread availability compared to other growth media.

Pan-drug resistance and hypervirulence in a human fungal pathogen are enabled by mutagenesis induced by mammalian body temperature.

The continuing emergence of invasive fungal pathogens poses an increasing threat to public health. Here, through the China Hospital Invasive Fungal Surveillance Net programme, we identified two independent cases of human infection with a previously undescribed invasive fungal pathogen, Rhodosporidiobolus fluvialis, from a genus in which many species are highly resistant to fluconazole and caspofungin. We demonstrate that R. fluvialis can undergo yeast-to-pseudohyphal transition and that pseudohyphal growth enhances its virulence, revealed by the development of a mouse model. Furthermore, we show that mouse infection or mammalian body temperature induces its mutagenesis, allowing the emergence of hypervirulent mutants favouring pseudohyphal growth. Temperature-induced mutagenesis can also elicit the development of pan-resistance to three of the most commonly used first-line antifungals (fluconazole, caspofungin and amphotericin B) in different Rhodosporidiobolus species. Furthermore, polymyxin B was found to exhibit potent activity against the pan-resistant Rhodosporidiobolus mutants. Collectively, by identifying and characterizing a fungal pathogen in the drug-resistant genus Rhodosporidiobolus, we provide evidence that temperature-dependent mutagenesis can enable the development of pan-drug resistance and hypervirulence in fungi, and support the idea that global warming can promote the evolution of new fungal pathogens.

Brilacidin, a novel antifungal agent against Cryptococcus neoformans.

Cryptococcus neoformans causes cryptococcosis, one of the most prevalent fungal diseases, generally characterized by meningitis. There is a limited and not very effective number of drugs available to combat this disease. In this manuscript, we show the host defense peptide mimetic brilacidin (BRI) as a promising antifungal drug against C. neoformans. BRI can affect the organization of the cell membrane, increasing the fungal cell permeability. We also investigated the effects of BRI against the model system Saccharomyces cerevisiae by analyzing libraries of mutants grown in the presence of BRI. In S. cerevisiae, BRI also affects the cell membrane organization, but in addition the cell wall integrity pathway and calcium metabolism. In vivo experiments show BRI significantly reduces C. neoformans survival inside macrophages and partially clears C. neoformans lung infection in an immunocompetent murine model of invasive pulmonary cryptococcosis. We also observed that BRI interacts with caspofungin (CAS) and amphotericin (AmB), potentiating their mechanism of action against C. neoformans. BRI + CAS affects endocytic movement, calcineurin, and mitogen-activated protein kinases. Our results indicate that BRI is a novel antifungal drug against cryptococcosis. IMPORTANCE: Invasive fungal infections have a high mortality rate causing more deaths annually than tuberculosis or malaria. Cryptococcosis, one of the most prevalent fungal diseases, is generally characterized by meningitis and is mainly caused by two closely related species of basidiomycetous yeasts, Cryptococcus neoformans and Cryptococcus gattii. There are few therapeutic options for treating cryptococcosis, and searching for new antifungal agents against this disease is very important. Here, we present brilacidin (BRI) as a potential antifungal agent against C. neoformans. BRI is a small molecule host defense peptide mimetic that has previously exhibited broad-spectrum immunomodulatory/anti-inflammatory activity against bacteria and viruses. BRI alone was shown to inhibit the growth of C. neoformans, acting as a fungicidal drug, but surprisingly also potentiated the activity of caspofungin (CAS) against this species. We investigated the mechanism of action of BRI and BRI + CAS against C. neoformans. We propose BRI as a new antifungal agent against cryptococcosis.

Antifungal drug penetration in soft tissue abscesses: a comparative analysis.

BACKGROUND: Invasive fungal infections (IFIs) are severe and difficult-to-treat infections affecting immunocompromised patients. Antifungal drug penetration at the site of infection is critical for outcome and may be difficult to achieve. Data about antifungal drug distribution in infected human tissues under real circumstances of IFI are scarce. METHODS: Multiple samples were obtained from soft tissue abscesses of a lung transplant patient with Candida albicans invasive candidiasis who underwent recurrent procedures of drainage, while receiving different consecutive courses of antifungal therapy [itraconazole (ITC), fluconazole, caspofungin]. Antifungal drug concentrations were measured simultaneously at the site of infection (surrounding inflammatory tissue and fluid content of the abscess) and in plasma for calculation of the tissue/plasma ratio (R). The concentration within the infected tissue was interpreted as appropriate if it was equal or superior to the MIC of the causal pathogen. RESULTS: A total of 30 tissue samples were collected for measurements of ITC (n = 12), fluconazole (n = 17) and caspofungin (n = 1). Variable concentrations were observed in the surrounding tissue of the lesions with median R of 2.79 (range 0.51-15.9) for ITC and 0.94 (0.21-1.37) for fluconazole. Concentrations ranges within the fluid content of the abscesses were 0.39-1.83 for ITC, 0.66-1.02 for fluconazole and 0.23 (single value) for caspofungin. The pharmacodynamic target (tissue concentration ≥ MIC) was achieved in all samples for all three antifungal drugs. CONCLUSIONS: This unique dataset of antifungal drug penetration in infected human soft tissue abscesses suggests that ITC, fluconazole and caspofungin could achieve appropriate concentrations in soft tissue abscesses.

Candida auris - Comparison of sensititre YeastOne and Vitek 2 AST systems for antifungal susceptibility testing - A single centre experience.

INTRODUCTION: Candida auris is emerging as an important cause of candidemia and deep seated candidal infection. We compared the susceptibility results of bloodstream Candida auris isolates by Vitek 2 with Sensititre YeastOne (SYO) method. METHODS: Forty-seven C. auris blood stream isolates were simultaneously tested for AFST by Vitek 2 and SYO. RESULTS: All strains were resistant to Fluconazole. 25.5% isolates showed pan-azole resistance. In comparison with SYO, lower MICs for voriconazole were noted with Vitek 2 (VME rate 76.1%). All strains were sensitive to anidulafungin and micafungin by SYO. For micafungin, Vitek 2 demonstrated higher MICs and an ME rate of 23.5%. Susceptibility interpretation of caspofungin by SYO was challenged by development of 'Eagle effect' resulting in sensitivity of 28.2%. We studied the evolution of caspofungin 'Eagle effect' with SYO by serial hourly MIC readings and noted that paradoxical growth commenced at 21 hrs of incubation. Compared to SYO, Vitek 2 showed higher resistance rate to Amphotericin B with ME rate of 25.6%. CONCLUSION: Laboratories using commercial AFST systems for Candida auris need to be aware of the possibility of ME and VME for amphotericin B and voriconazole respectively with Vitek 2 and 'Eagle effect' for caspofungin with SYO.

Correlation between antifungal clinical practices and a new clinical decision support system ANTIFON-CLIC® for the treatment of invasive candidiasis: a retrospective multicentre study.

BACKGROUND: Invasive candidiasis is still recognized as a major cause of morbidity and mortality. To support clinicians in the optimal use of antifungals for the treatment of invasive candidiasis, a computerized decision support system (CDSS) was developed based on institutional guidelines. OBJECTIVES: To evaluate the correlation of this newly developed CDSS with clinical practices, we set-up a retrospective multicentre cohort study with the aim of providing the concordance rate between the CDSS recommendation and the medical prescription (NCT05656157). PATIENTS AND METHODS: Adult patients who received caspofungin or fluconazole for the treatment of an invasive candidiasis were included. The analysis of factors associated with concordance was performed using mixed logistic regression models with department as a random effect. RESULTS: From March to November 2022, 190 patients were included from three centres and eight departments: 70 patients from centre A, 84 from centre B and 36 from centre C. Overall, 100 patients received caspofungin and 90 received fluconazole, mostly (59%; 112/190) for empirical/pre-emptive treatment. The overall percentage of concordance between the CDSS and medical prescriptions was 91% (173/190) (confidence interval 95%: 82%-96%). No significant difference in concordance was observed considering the centres (P > 0.99), the department of inclusion (P = 0.968), the antifungal treatment (P = 0.656) or the indication of treatment (P = 0.997). In most cases of discordance (n = 13/17, 76%), the CDSS recommended fluconazole whereas caspofungin was prescribed. The clinical usability evaluated by five clinicians was satisfactory. CONCLUSIONS: Our results demonstrated the high correlation between current antifungal clinical practice and this user-friendly and institutional guidelines-based CDSS.

Microevolution of Candida glabrata (Nakaseomyces glabrata) during an infection.

Candida glabrata (Nakaseomyces glabrata) is an emergent and opportunistic fungal pathogen that colonizes and persists in different niches within its human host. In this work, we studied five clinical isolates from one patient (P7), that have a clonal origin, and all of which come from blood cultures except one, P7-3, obtained from a urine culture. We found phenotypic variation such as sensitivity to high temperature, oxidative stress, susceptibility to two classes of antifungal agents, and cell wall porosity. Only isolate P7-3 is highly resistant to the echinocandin caspofungin while the other four isolates from P7 are sensitive. However, this same isolate P7-3, is the only one that displays susceptibility to fluconazole (FLC), while the rest of the isolates are resistant to this antifungal. We sequenced the PDR1 gene which encodes a transcription factor required to induce the expression of several genes involved in the resistance to FLC and found that all the isolates encode for the same Pdr1 amino acid sequence except for the last isolate P7-5, which contains a single amino acid change, G1099C in the putative Pdr1 transactivation domain. Consistent with the resistance to FLC, we found that the CDR1 gene, encoding the main drug efflux pump in C. glabrata, is highly overexpressed in the FLC-resistant isolates, but not in the FLC-sensitive P7-3. In addition, the resistance to FLC observed in these isolates is dependent on the PDR1 gene. Additionally, we found that all P7 isolates have a different proportion of cell wall carbohydrates compared to our standard strains CBS138 and BG14. In P7 isolates, mannan is the most abundant cell wall component, whereas ß-glucan is the most abundant component in our standard strains. Consistently, all P7 isolates have a relatively low cell wall porosity compared to our standard strains. These data show phenotypic and genotypic variability between clonal isolates from different niches within a single host, suggesting microevolution of C. glabrata during an infection.

Modeling of intravenous caspofungin administration using an intestine-on-chip reveals altered Candida albicans microcolonies and pathogenicity.

Candida albicans is a commensal yeast of the human intestinal microbiota that, under predisposing conditions, can become pathogenic and cause life-threatening systemic infections (candidiasis). Fungal-host interactions during candidiasis are commonly studied using conventional 2D in vitro models, which have provided critical insights into the pathogenicity. However, microphysiological models with a higher biological complexity may be more suitable to mimic in vivo-like infection processes and antifungal drug efficacy. Therefore, a 3D intestine-on-chip model was used to investigate fungal-host interactions during the onset of invasive candidiasis and evaluate antifungal treatment under clinically relevant conditions. By combining microbiological and image-based analyses we quantified infection processes such as invasiveness and fungal translocation across the epithelial barrier. Additionally, we obtained novel insights into fungal microcolony morphology and association with the tissue. Our results demonstrate that C. albicans microcolonies induce injury to the epithelial tissue by disrupting apical cell-cell contacts and causing inflammation. Caspofungin treatment effectively reduced the fungal biomass and induced substantial alterations in microcolony morphology during infection with a wild-type strain. However, caspofungin showed limited effects after infection with an echinocandin-resistant clinical isolate. Collectively, this organ-on-chip model can be leveraged for in-depth characterization of pathogen-host interactions and alterations due to antimicrobial treatment.

Pulmonary surfactant impacts in vitro activity of selected antifungal drugs against Candida krusei and Candida albicans.

PURPOSE: This study investigates how surfactants affect the in-vitro anti-infective efficacy of micafungin, caspofungin, anidulafungin, and amphotericin B in treating pulmonary mycoses. METHODS: MIC values for antifungal agents were determined against Candida krusei (now Pichia kudriavzevii) ATCC 6258, Candida albicans ATCC 90028, and 18 clinical isolates using the broth microdilution method in RPMI medium, following EUCAST recommendations. MIC assays included testing with and without Curosurf® surfactant at 1 mg/mL for C. krusei ATCC 6258 and all C. krusei isolates. Subsequent Time-kill studies in Sabouraud broth involved testing both C. albicans ATCC 90028 and C. krusei ATCC 6258 strains at concentrations equal their respective MIC values, with and without surfactant, using all four antifungals. CFU/mL were assessed at multiple time points up to 24 h. TKCs with different surfactant concentrations for C. krusei ATCC 6258 and mini-TKCs at various concentrations relative to the MIC of C. krusei isolates and the reference strain were conducted with micafungin, anidulafungin, and caspofungin. RESULTS: MIC results showed that 1 µg/mL surfactant reduced killing of micafungin and anidulafungin against C. krusei, while caspofungin was unaffected. Amphotericin B's MIC decreased by half. TKCs demonstrated significant effects of surfactant on micafungin and anidulafungin against C. krusei, with complete abolition of anidulafungin's activity against C. albicans. CONCLUSION: This in-vitro study highlights the concentration-dependent inhibitory effect of surfactant on antifungal activity against C. krusei and, to some extent, C. albicans, necessitating further clinical validation for invasive lung mycoses treatment.

Efficacy and safety of caspofungin for the treatment of invasive pulmonary aspergillosis in patients with chronic obstructive pulmonary disease.

OBJECTIVES: We assessed the efficacy of a 3-week primary or salvage caspofungin regimen in patients with chronic obstructive pulmonary disease (COPD) and concomitant proven or suspected invasive pulmonary aspergillosis (IPA). METHODS: Forty-four patients were treated with an initial loading caspofungin dose of 70 mg, followed by a daily dose of 50 mg for 20 days. The main efficacy endpoint was clinical effectiveness. Secondary endpoints included the clinical efficacy of caspofungin after 1 week, therapeutic efficacy based on the European Organization for Research and Treatment of Cancer and Mycoses Study Group Education and Research Consortium (EORTC/MSG) criteria, the sensitivity of different Aspergillus strains to caspofungin in vitro, and the safety of caspofungin. RESULTS: An assessment of 42 patients in the intention-to-treat group revealed efficacy rates of 33.33% within 1 week and 38.10% within 3 weeks. According to the EORTC/MSG criteria, the treatment success rate was 38.10%. The success rate of first-line treatment was 54.76%, whereas salvage treatment had a success rate of 45.24%. No adverse events were reported among the participants. CONCLUSIONS: Caspofungin is effective and safe as an initial or salvage treatment for patients with IPA and COPD.

Novel automated antifungal susceptibility testing system for yeasts based on dual-detection algorithm of turbidimetry and colorimetry.

Introduction. The increasing prevalence and growing resistance of fungi present a significant peril to public health. There are only four classes of antifungal medicines available today, and few candidates are in clinical trials.Hypothesis/Gap Statement. Rapid and sensitive diagnostic techniques are lacking for most fungal pathogens, and those that do exist are expensive or hard to obtain.Aim. This study aimed to evaluate the feasibility of a novel automated antifungal susceptibility testing system, Fungus AST, in comparison to the broth microdilution method (BMD) recommended by the Clinical and Laboratory Standards Institute (CLSI).Methodology. A total of 101 clinical Candida spp. isolates were collected from the Zengcheng Branch of Nanfang Hospital and subjected to antifungal susceptibility testing. Antifungal susceptibility was assessed using the Fungus AST method and the BMD.Results. In this study, we introduce a novel automated antifungal susceptibility testing system, Fungus AST, which detects the turbidity and/or colour intensity of microdilution wells using a four-wavelength detection technology in real time and is designed to match the growth characteristics of strains over time. Based on our analysis, all reportable ranges of Fungus AST were suitable for clinical fungal isolates in PR China. Within ±twofold dilutions, reproducibility was 100 %. Considering the BMD as a referenced method, ten antifungal agents (anidulafungin, caspofungin, micafungin, fluconazole, voriconazole, posaconazole, itraconazole, amphotericin B, 5-flucytosine and nystatin) showed an essential agreement of >95 %. The category agreement of five antifungal agents (anidulafungin, caspofungin, micafungin, fluconazole and voriconazole) was excellent at >90 %. One Candida albicans isolate and voriconazole showed a major error (ME) (1.7 %), and no other ME or very ME agents were found.Conclusion. Given the above, it can be argued that the utilization of Fungus AST is a discretionary automated approach. More improvements are needed in Fungus AST compared to the BMD system for a wider range of clinical isolates, including different types of fungi.

Rise and fall of Caspofungin: the current status of Caspofungin as a treatment for Cryptococcus neoformans infection.

Antifungal infections are becoming a major concern to human health due to antimicrobial resistance. Echinocandins have been promising agents against resistant fungal infections, primarily caspofungin, which has a more effective mechanism of action than azoles and polyenes. However, fungi such as Cryptococcus neoformans appear to be inheritably resistant to these drugs, which is concerning due to the high clinical importance of C. neoformans. In this review, we review the history of C. neoformans and the treatments used to treat antifungals over the years, focusing on caspofungin, while highlighting the C. neoformans problem and possible explanations for its inherent resistance.

Caspofungin is a drug used to treat several types of fungal infections. Resistance to caspofungin is a huge problem, especially in those that are immunocompromised. It is important to understand the history of caspofungin discovery, its clinical applications and its mechanism of action, as well as if a new drug target could be used overcome resistance. This review may perform guide new studies combining caspofungin with other drugs and indicate new potential targets for caspofungin.