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PURPOSE: The purpose of this study was to assess the association between antifungal susceptibility as measured by minimum inhibitory concentration (MIC) and clinical outcomes in fungal keratitis. METHODS: This pre-specified secondary analysis of the Mycotic Ulcer Treatment Trial II (MUTT II) involved patients with filamentous fungal keratitis presenting to Aravind Eye Hospitals in South India. Antifungal susceptibility testing for natamycin and voriconazole was performed on all samples with positive fungal culture results according to Clinical and Laboratory Standards Institute Guidelines. The relationship between MIC and clinical outcomes of best-corrected visual acuity, infiltrate or scar size, corneal perforation, need for therapeutic penetrating keratoplasty, and time to re-epithelialization were assessed. RESULTS: We obtained MIC values from 141 patients with fungal keratitis. The most commonly cultured organisms were Aspergillus (46.81%, n = 66) and Fusarium (44.68%, n = 63) species. Overall, there was no association between antifungal MICs and clinical outcomes. Subgroup analysis revealed that among Fusarium-positive cases, higher voriconazole MIC was correlated with worse three-month best-corrected visual acuity (p = 0.03), increased need for therapeutic penetrating keratoplasty (p = 0.04), and time to re-epithelialization (p = 0.03). No significant correlations were found among Aspergillus-positive cases. There were no significant correlations found between natamycin MIC and clinical outcomes among organism subgroups. CONCLUSIONS: Decreased susceptibility to voriconazole was associated with increased odds of requiring a therapeutic penetrating keratoplasty in Fusarium-positive cases. Susceptibility to natamycin was not associated with any of the measured outcomes.

Purpose: Dematiaceous fungi, the third most common causative organism of fungal keratitis, constitute 3.5% to 43.5% of fungal keratitis worldwide. Several studies on filamentous fungi (Aspergillus and Fusarium) are available as opposed to that on dematiaceous fungal keratitis. This study aims to describe the profile of dematiaceous fungal keratitis in South India. Methods: This institutional cohort study on culture-proven dematiaceous fungal keratitis was performed in a single ophthalmology referral center in South India for a 6-year period. Records were analyzed for demographic, clinical, microbiological, and treatment outcomes for 3 months from the date of presentation. Results: This study comprised 312 cases involving dematiaceous fungal keratitis (DFK). During the study period, DFK accounted for 10% of microbial keratitis and 24.6% of fungal keratitis cases. The mean (standard deviation) age was 54 (14) years. Males were commonly affected (73.4%). Keratitis was ≤1/3rd depth in 47.8% of cases. Fifty-four cases (17.3%) demonstrated surface pigmentation, and 69 cases (22.1%) had endothelial plaque. Curvularia spp. (99 eyes, 31.7%) was the most common fungal isolate among the speciated fungi. Topical medications resulted in the healing of 63.5% of cases. A total of 193 cases (79%) healed, and 49 cases had to undergo therapeutic penetrating keratoplasty (TPK). Early TPK was performed for 20 cases (40.8%). Seventeen eyes (34.6%) maintained clear grafts at the end of 3 months. Conclusion: In this extensive study on DFK, we report a high incidence of this group of fungal keratitis. We found an excellent healing rate in our cohort of patients. [ABSTRACT FROM AUTHOR]

The application of ketoconazole (KET) in ocular drug delivery is restricted by its poor aqueous solubility though its broad-spectrum antifungal activity. The aim of this study is to develop an ion-sensitive in situ gel (ISG) of KET to promote its ocular bioavailability in topical application. The solubility of KET in water was increased by complexation with hydroxypropyl-β-cyclodextrin (HPβCD), then KET-HPβCD inclusion complex (KET-IC) was fabricated into an ion-sensitive ISG triggered by sodium alginate (SA). The in vitro drug release and antifungal activities investigations demonstrated that the KET-IC-ISG formulation increased drug release and anti-fungal activities compared to pure KET. The ex vivo rabbit corneal permeation studied demonstrated higher permeability of KET-IC-ISG formulation (Papp of (6.34 ± 0.21) × 10−4 cm/h) than pure KET (Papp of (3.09 ± 0.09) × 10−4 cm/h). The cytotoxicity assay and the ocular irritation study in rabbits confirmed the KET-IC-ISG safety and well tolerance. The ocular pharmacokinetics of KET in rabbits was investigated and the results showed that the KET-IC-ISG increased its bioavailability in cornea by 47-fold. In conclusion, the KET-IC-ISG system promoted the precorneal retention, the ocular drug bioavailability and the developed formulation is a potential strategy to treat mycotic keratitis. [ABSTRACT FROM AUTHOR]

Purpose: To report a rare case of fungal keratitis caused by Cryptococcus neoformans, highlighting its unique morphological features using in vivo confocal microscopy (IVCM). Methods: This was a retrospective case report. A 66-year-old man presented with foreign body sensation and blurred vision in his left eye for over 10 months. Results: His best-corrected visual acuity was 20/20. Slit-lamp examination revealed a gray-white lesion approximately 4–5 mm in the superficial layer of the central cornea without epithelial defects. The IVCM images revealed numerous round or round-like pathogens, each with a central highly reflective body surrounded by a dark ring, ranging in size from 5 to 30 µm, and to a maximum of 85 µm, observed in the corneal epithelium and superficial stroma. No obvious inflammatory cell infiltration was observed in the lesions or endothelium. C. neoformans infection was confirmed. The round pathogens completely disappeared after 8 weeks of treatment with topical amphotericin B and voriconazole eye drops. Conclusion: Fungal keratitis caused by C. neoformans is rare and easily overlooked due to atypical clinical signs and symptoms. This case reports the unique morphological features of C. neoformans in the cornea using IVCM for the first time, facilitating rapid, noninvasive auxiliary diagnosis of C. neoformans keratitis and treatment follow-up. [ABSTRACT FROM AUTHOR]

Objective: The fungal unfolded protein response consists of a two-component relay in which the ER-bound sensor, IreA, splices and activates the mRNA of the transcription factor, HacA. Previously, we demonstrated that hacA is essential for Aspergillus fumigatus virulence in a murine model of fungal keratitis (FK), suggesting the pathway could serve as a therapeutic target. Here we investigate the antifungal properties of known inhibitors of the mammalian Ire1 protein both in vitro and in a treatment model of FK. Methods: The antifungal activity of Ire1 inhibitors was tested against conidia of several A. fumigatus isolates by a broth microdilution assay and against fungal biofilm by XTT reduction. The influence of 4μ8C on hacA mRNA splicing in A. fumigatus was assessed through gel electrophoresis and qRT-PCR of UPR regulatory genes. The toxicity and antifungal profile of 4μ8C in the cornea was assessed by applying drops to uninfected or A. fumigatus -infected corneas 3 times daily starting 4 hours post-inoculation. Corneas were evaluated daily through slit-lamp imaging and optical coherence tomography, or at endpoint through histology or fungal burden quantification via colony forming units. Results: Among six Ire1 inhibitors screened, the endonuclease inhibitor 4μ8C displayed the strongest antifungal profile with an apparent fungicidal action. The compound both blocked conidial germination and hyphal metabolism of A. fumigatus Af293 in the same concentration range that blocked hacA splicing and UPR gene induction (60-120 µM). Topical treatment of sham-inoculated corneas with 0.5 and 2.5 mM 4μ8C did not impact corneal clarity, but did transiently inhibit epithelialization of corneal ulcers. Relative to vehicle-treated Af293-infected corneas, treatment with 0.5 and 2.5 mM drug resulted in a 50% and >90% reduction in fungal load, respectively, the latter of which corresponded to an absence of clinical signs of infection or corneal pathology. Conclusion: The in vitro data suggest that 4μ8C displays antifungal activity against A. fumigatus through the specific inhibition of IreA. Topical application of the compound to the murine cornea can furthermore block the establishment of infection, suggesting this class of drugs can be developed as novel antifungals that improve visual outcomes in FK patients. [ABSTRACT FROM AUTHOR]

Fungi are very common infectious pathogens, which may cause invasive and potentially life-threatening infections. However, the efficacy of antifungal medications remains limited. Herein, a Cu2+-phenolic nanoflower is designed to combat fungal infections by combining cuproptosis and cell wall digestion. Firstly, protocatechuic acid (PA)-Cu2+ (PC) nanopetals are prepared by coordination interaction. Lywallzyme (Lyw) is then added to induce the self-assembly of PC to form Lyw loaded PC (PCW) nanoflowers. PCW nanoflowers can effectively adhere to fungal surface and Lyw can digest fungal cell walls to facilitate Cu2+ to penetrate into fungal interior, thereby exerting a synergistic fungicidal effect. PCW nanoflowers exhibit excellent fungicidal activity even in protein-rich and high-salt conditions, where dissociative Cu2+ completely loses fungicidal activity. Transcriptome sequencing analysis reveals that PCW can lead to fungal cuproptosis. The in vivo fungicidal effect of PCW nanoflowers is confirmed on a murine skin fungal infection model and a murine fungal keratitis model. Fungal infections can be debilitating and life-threatening. Here, the authors report a fungicidal strategy by the combination of cell wall digestion and cuproptosis using lywallzyme-assembled copper-phenolic nanoflowers demonstrating synergistic effects in fungal infection and fungal keratitis models. [ABSTRACT FROM AUTHOR]

Fungal keratitis (FK), a severe eye infection that leads to vision impairment and blindness, poses a high risk to contact lens users, and Candida albicans remains the most common underpinning fungal pathogen in temperate climates. Patients are initially treated empirically (econazole 1% drops hourly for 24–48 h), and if there is no response, amphotericin B (AmB) 0.15% eye drops (extemporaneously manufactured to be stable for a week) are the gold-standard treatment. Here, we aim to develop a sustained-release AmB ocular film to treat FK with an enhanced corneal retention time. As there is a paucity of reliable in vitro models to evaluate ocular drug release and antifungal efficacy under flow, we developed a 3D-printed microfluidic device based on four chambers stacked in parallel, in which lenses previously inoculated with a C. albicans suspension were placed. Under the flow of a physiological fluid over 24 h, the release from the AmB-loaded film that was placed dry onto the surface of the wetted contact lenses was quantified, and their antifungal activity was assessed. AmB sodium deoxycholate micelle (dimeric form) was mixed with sodium alginate and hyaluronic acid (3:1 w/w) and cast into films (0.48 or 2.4%), which showed sustained release over 24 h and resulted in a 1.23-fold reduction and a 5.7-fold reduction in CFU/mL of C. albicans, respectively. This study demonstrates that the sustained delivery of dimeric AmB can be used for the treatment of FK and provides a facile in vitro microfluidic model for the development and testing of ophthalmic antimicrobial therapies. [ABSTRACT FROM AUTHOR]

Purpose: We report two cases of fungal keratitis due to rare melanized fungal pathogens in ocular infection, one is the first case report of keratitis due to Pseudopithomyces maydicus and the second is keratitis due to rare fungal pathogen in ocular infections Phialophora chinensis. Method: Conventional mycology during routine diagnostics helped in identifying these rare fungal isolates, following which we proceeded for the confirmation of identification by DNA sequencing and did in-vitro antifungal susceptibility test to understand their susceptibility pattern. The clinical information for these two patients were collected from hospital electronic medical records. Results: We discuss the clinical presentation, treatment given, and clinical outcome in these patients and correlate these with the conventional microbiology and sequencing techniques, which helped in identifying the pathogen and the in-vitro antifungal susceptibility of these rare isolates. We also do a brief literature review for these two rare fungal pathogens. Conclusions: Pseudopithomyces maydicus and Phialophora chinensis are rare causes of fungal keratitis due to melanized fungi. Both of this fungal keratitis respond well to medical therapy alone if diagnosed and treated early. [ABSTRACT FROM AUTHOR]

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Aim: The aim of this study was to investigate whether Dectin-1 influences the immune-inflammatory response in A. fumigatus keratitis by modulating macrophage polarization. Methods: 1. The models of 1-day, 3-day, and 5-day of fungal keratitis were established in SPF C57BL/6 mice after stimulation by A. fumigatus. Dectin-1 agonist (curdlan) and antagonist (laminaran) were injected separately in the mouse subconjunctivae for 1 day in the established mouse model of A. fumigatus keratitis; PBS was used as the control. Inflammation of the mouse cornea was observed under a slit lamp to obtain a clinical score. 2. The expression of M1 (TNF-a, INOS, IL-6, IL-12) and M2 (Arg-1, IL-10, Fizz-1, Ym-1) cytokine-encoding mRNAs was quantified by RT-PCR. 3. Changes in the number of macrophages and expression of M1 and M2 macrophages in mouse corneas detected by immunofluorescence and flow cytometry. 4. Pre-treatment of RAW264.7 cells with MAPK cell signaling pathway inhibitors SB203580 (p38 inhibitor, 10µM), U0126 (ERK inhibitor, 20µM), SP600125 (JNK inhibitor, 10µM) and DMSO separately for 2 h, and stimulated by A. fumigatus for 12 h. Changes in the mRNA expression of M1 and M2 cytokines in the macrophages were quantified by RT-PCR. Results: 1. With curdlan pre-treatment, mouse corneal inflammation worsened, and the clinical score increased after infection. In contrast, in the laminaran pretreated group, corneal inflammation was alleviated and the clinical score decreased significantly compared to the PBS group after infection. 2. Compared with the control group, the expression levels of macrophage phenotype-related M1 and M2 cytokine mRNAs increased significantly 1, 3, and 5 days after A. fumigatus infected the corneas of mice. 3. With curdlan pretreatment, the expression of mRNAs encoding M1 cytokines increased, while those encoding M2 cytokines decreased in the cornea compared to the PBS group. In contrast, after infection, mRNA levels for M1 cytokines decreased significantly and those for M2 cytokines increased in the cornea of the laminaran pre-treated group compared to the PBS group. 4. The number of macrophages in the corneal stroma of mice in the curdlan pretreatment group increased significantly compared with the PBS group, while in the laminaran pretreatment group this number decreased significantly. 5. The results of flow cytometry showed that after 3 days of mouse corneal A. fumigatus infection, the number of macrophages in the mouse A. fumigatus model in the curdlan pretreatment group was increased (10.4%) and the number of macrophages in the mouse A. fumigatus model in the laminaran pretreatment group (6.31%), when compared with the AF+FBS group (7.91%). The proportion of M1-type macrophages was increased in the curdlan pretreated group (55.6%) compared to the AF+FBS group (51.2%), the proportion of laminaran pretreatment group had a decreased proportion of M1-type macrophages (46.8%); while M2-type macrophages were the opposite of M1-type: the proportion of M2-type macrophages was 49.2% in the AF+FBS group, the proportion of M2-type macrophages was decreased in the curdlan pretreatment group (44.0%), and the proportion of M2-type macrophages was increased in the laminaran pretreatment group (53.5%). 6. Expression of M1 and M2 cytokine-encoding mRNAs decreased and increased, respectively, after infection, in the RAW264.7 cells pre-treated with MAPK pathway inhibitors, compared to the control. Conclusion: In a mouse model of A. fumigatus keratitis, Dectin-1 can affect macrophage recruitment and polarization, may regulate macrophage phenotype-associated factor changes through the MAPK signaling pathway [ABSTRACT FROM AUTHOR]

AbstractPurposeMethodsResultsConclusionFungal keratitis (FK) is a difficult condition to treat, particularly in underdeveloped nations. The study aimed to compare the in vitro activity of chlorhexidine (CHX) and seven antifungal agents against a collection of fungi recovered from FK patients.Seventy-three fungi were collected from patients with FK included in study. The antifungal agents tested were fluconazole, voriconazole, posaconazole, miconazole, natamycin, amphotericin B, and caspofungin. The concentration range for CHX was 1–1024 μg/mL. Assessments of antifungal susceptibility were conducted using the EUCAST broth microdilution reference method.The findings demonstrated the beneficial in vitro inhibition of filamentous and yeast fungi by CHX. CHX demonstrated efficacy against Fusarium spp., Aspergillus spp., Candida spp., S. apiospermum and dematiceous fungi at concentrations of 4–64, 32–64, 4–32, 8, and 4–16 µg/mL respectively. The median MICs and MIC distributions of CHX showed no significant differences among the evaluated spp. (p > 0.05). The most effective antifungal drug was posaconazole, which was followed by voriconazole, caspofungin, and amphotericin B.In situations where access to a range of antifungal medications and microbiological facilities is limited, CHX should be further investigated as a potential treatment for FK. It might be able to treat the condition as an inexpensive topical treatment. [ABSTRACT FROM AUTHOR]

Itraconazole (ITZ) is one of the broad-spectrum antifungal agents for treating fungal keratitis. In clinical use, ITZ has problems related to its poor solubility in water, which results in low bioavailability when administered orally. To resolve the issue, we formulated ITZ into the inclusion complex (ITZ-IC) system using β-cyclodextrin (β-CD), which can potentially increase the solubility and bioavailability of ITZ. The molecular docking study has confirmed that the binding energy of ITZ with the β-CD was −5.0 kcal/mol, indicating a stable conformation of the prepared inclusion complex. Moreover, this system demonstrated that the inclusion complex could significantly increase the solubility of ITZ up to 4-fold compared to the pure drug. Furthermore, an ocular drug delivery system was developed through dissolving microneedle (DMN) using polyvinyl pyrrolidone (PVP) and polyvinyl alcohol (PVA) as polymeric substances. The evaluation results of DMN inclusion complexes (ITZ-IC-DMN) showed excellent mechanical strength and insertion ability. In addition, ITZ-IC-DMN can dissolve rapidly upon application. The ex vivo permeation study revealed that 75.71% (equivalent to 3.79 ± 0.21 mg) of ITZ was permeated through the porcine cornea after 24 h. Essentially, ITZ-IC-DMN exhibited no signs of irritation in the HET-CAM study, indicating its safety for application. In conclusion, this study has successfully developed an inclusion complex formulation containing ITZ using β-CD in the DMN system. This approach holds promise for enhancing the solubility and bioavailability of ITZ through ocular administration. [ABSTRACT FROM AUTHOR]

Background: Infectious keratitis poses a significant public health challenge worldwide, with variable incidence rates reported globally. Timely diagnosis and intervention are crucial to prevent ocular morbidity and potential blindness. Aims and Objectives: This study aimed to study and investigate the epidemiology, risk factors, etiology, clinical progression, microbiological findings, and treatment outcomes of microbial keratitis in a tertiary care center in western India. Materials and Methods: We conducted a prospective observational study from July 2020 to July 2022, enrolling 90 patients with suspected microbial keratitis. Clinical data were collected, and statistical analysis was performed using SPSS 26.0, with P<0.05 considered statistically significant. Results: Most patients were males (67.80%) and laborers (27.8%) from urban areas, with fungal keratitis being more prevalent in rural regions. No statistically significant associations were found between keratitis type and demographic factors, such as age, gender, occupation, or socioeconomic status. Bacterial keratitis was more common in urban areas. Delayed presentation was linked to larger ulcers and worse visual outcomes. Fungal keratitis presented with smaller but deeper ulcers compared to bacterial keratitis. We found 8.06% positivity rate for Gram and KOH stain each. Microbiological cultures identified bacteria and fungi in 11.29% and 20.97% samples, respectively. Treatment varied from topical medications to surgery, with 26.67% of patients receiving both. Conclusion: Our findings underscore the importance of prompt diagnosis, targeted treatment, and comprehensive microbiological workup in managing microbial keratitis to prevent vision and eye loss. Further research is warranted to enhance understanding and optimize management strategies for this sight-threatening condition. [ABSTRACT FROM AUTHOR]

Purpose: To review the clinical features, risk factors, microbiological profile, and treatment regimens of fungal keratitis in Galicia, a region in Northwestern Spain with temperate humid weather. Patients and methods: A retrospective case series was employed, including patients with fungal keratitis from nine hospitals within the region of Galicia, Spain, between 2010 and 2020. Data obtained from clinical records were analysed. Results: Out of 654 cases of infectious keratitis, 77 cases (9.9%) were identified as fungal keratitis. The median age of affected patients was 68.0 years, with a higher incidence in rural areas (62.3%). Candida spp. infections were the most frequent type (55.8%) and were associated with a higher median age than were the non-dermatophyte mould infections. The primary risk factors included steroid eyedrop use (29.9%), recent keratoplasty (18.2%), ocular trauma (19.5%), and contact with vegetable matter (11.7%). Most ulcers displayed stromal involvement, and 37.7% presented corneal thinning. The median duration of infection was longer in fungal than in bacterial keratitis, and surgical intervention was required in 48.1% of cases. Conclusions: Fungal keratitis, mainly involving Candida spp., accounted for 9.9% of microbial keratitis cases in Galicia, Spain, with significant risk factors being topical steroid use, ocular trauma, and contact with vegetable matter. Delayed diagnosis often resulted in poor outcomes, highlighting the need for early detection through awareness and new technologies to improve prognosis. [ABSTRACT FROM AUTHOR]

Xueyun Fu,&ast; Xue Tian,&ast; Jing Lin, Qian Wang, Lingwen Gu, Ziyi Wang, Menghui Chi, Bing Yu, Zhuhui Feng, Wenyao Liu, Lina Zhang, Cui Li, Guiqiu Zhao Department of Ophthalmology, The Affiliated Hospital of Qingdao University, Qingdao, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Cui Li; Guiqiu Zhao, Department of Ophthalmology, Affiliated Hospital of Qingdao University, 16 Jiangsu Road, Qingdao, Shandong, 266003, People’s Republic of China, Email yankelicui@126.com; zhaoguiqiu_good@126.comBackground: Fungal keratitis is a serious blinding eye disease. Traditional drugs used to treat fungal keratitis commonly have the disadvantages of low bioavailability, poor dispersion, and limited permeability.Purpose: To develop a new method for the treatment of fungal keratitis with improved bioavailability, dispersion, and permeability.Methods: Zeolitic Imidazolate Framework-8 (ZIF-8) was formed by zinc ions and 2-methylimidazole linked by coordination bonds and characterized by Scanning electron microscopy (SEM), X-ray diffraction (XRD), and Zeta potential. The safety of ZIF-8 on HCECs and RAW 264.7 cells was detected by Cell Counting Kit-8 (CCK-8). Safety evaluation of ZIF-8 on mice corneal epithelium was conducted using the Draize corneal toxicity test. The effects of ZIF-8 on fungal growth, biofilm formation, and hyphae structure were detected by Minimal inhibit concentration (MIC), crystal violet staining, Propidium Iodide (PI) testing, and calcofluor white staining. The anti-inflammatory effects of ZIF-8 on RAW 246.7 cells were evaluated by Quantitative Real-Time PCR Experiments (qPCR) and Enzyme-linked immunosorbent assay (ELISA). Clinical score, Colony-Forming Units (CFU), Hematoxylin-eosin (HE) staining, and immunofluorescence were conducted to verify the therapeutic effect of ZIF-8 on C57BL/6 female mice with fungal keratitis.Results: In vitro, ZIF-8 showed outstanding antifungal effects, including inhibiting the growth of Aspergillus fumigatus over 90% at 64 μg/mL, restraining the formation of biofilm, and destroying cell membranes. In vivo, treatment with ZIF-8 reduced corneal fungal load and mitigated neutrophil infiltration in fungal keratitis, which effectively reduced the severity of keratitis in mice and alleviated the infiltration of inflammatory factors in the mouse cornea. In addition, ZIF-8 reduces the inflammatory response by downregulating the expression of pro-inflammatory cytokines TNF-α, IL-6, and IL-1β after Aspergillus fumigatus infection in vivo and in vitro.Conclusion: ZIF-8 has a significant anti-inflammatory and antifungal effect, which provides a new solution for the treatment of fungal keratitis.Keywords: fungal keratitis, MOFs, antifungal, anti-inflammatory, ZIF-8

Fungal keratitis is a serious blinding eye disease. The development of fungal infections depends primarily on the interaction of fungal virulence with host immune defense factors. The cornea is considered an immune-privileged organ, and resident macrophages are the main immune cells that respond to the heterogeneity exhibited by the microenvironment with their polarization. In the early stage of infection, macrophages polarize towards M1, which promotes inflammation and facilitates fungal clearance but produces a cellular storm that exacerbates immune damage; in the late stage of infection, macrophages polarize towards M2, which suppresses the inflammatory response and facilitates tissue repair, but may be immunosuppressed or even immune escape to the detriment of pathogen clearance. The balance between pro-inflammatory and anti-inflammatory responses is key to maintaining the functional integrity of the cornea. Current antifungal drug therapy is limited, so it is particularly important to find a therapeutic target for the inflammatory response triggered by the immune response in addition to antifungal therapy. In this review, the functional and phenotypic characterization of macrophage subsets associated with fungal keratitis was reviewed, more in-depth research is needed to explore the specific mechanisms by which macrophage polarization and their impact on fungal keratitis. Targeted regulation of macrophage differentiation based on their phenotype and function could be an effective approach to treat and manage fungal keratitis in the future.

Abstract Purpose The purpose of this study was to assess the association between antifungal susceptibility as measured by minimum inhibitory concentration (MIC) and clinical outcomes in fungal keratitis. Methods This pre-specified secondary analysis of the Mycotic Ulcer Treatment Trial II (MUTT II) involved patients with filamentous fungal keratitis presenting to Aravind Eye Hospitals in South India. Antifungal susceptibility testing for natamycin and voriconazole was performed on all samples with positive fungal culture results according to Clinical and Laboratory Standards Institute Guidelines. The relationship between MIC and clinical outcomes of best-corrected visual acuity, infiltrate or scar size, corneal perforation, need for therapeutic penetrating keratoplasty, and time to re-epithelialization were assessed. Results We obtained MIC values from 141 patients with fungal keratitis. The most commonly cultured organisms were Aspergillus (46.81%, n = 66) and Fusarium (44.68%, n = 63) species. Overall, there was no association between antifungal MICs and clinical outcomes. Subgroup analysis revealed that among Fusarium-positive cases, higher voriconazole MIC was correlated with worse three-month best-corrected visual acuity (p = 0.03), increased need for therapeutic penetrating keratoplasty (p = 0.04), and time to re-epithelialization (p = 0.03). No significant correlations were found among Aspergillus-positive cases. There were no significant correlations found between natamycin MIC and clinical outcomes among organism subgroups. Conclusions Decreased susceptibility to voriconazole was associated with increased odds of requiring a therapeutic penetrating keratoplasty in Fusarium-positive cases. Susceptibility to natamycin was not associated with any of the measured outcomes.

Abstract Backroud Keratitis caused by Lasiodiplodia theobromae is rare and typically associated with a poor prognosis. Current literature lacks sufficient evidence on effective management of patients with this condition. Case presentation A 74-year-old former agricultural worker presented with a red right eye, discomfort, and decreased visual acuity, progressing over three days without treatment. Examination revealed type 2 diabetes and a non-perforating, spiculated corneal abscess with a hypopyon in the right eye. Initial treatment included a triple antibiotic therapy and supportive care. Direct mycological examination identified numerous septate mycelial filaments. Antifungal treatment with natamycin and voriconazole, both topically and orally, was initiated. Cultures confirmed Lasiodiplodia theobromae. The patient showed significant improvement. Treatment continued for eight weeks, with a final visual acuity of 20/50 due to a stromal scar. Conclusion An extensive literature review conducted in November 2023, using databases such as PubMed and Google Scholar with the keywords “lasiodiplodia” and “keratitis” yielded no previous cases of this specific condition being managed solely with the combined use of natamycin and voriconazole. This antifungal combination is commonly included in most management protocols for fungal keratitis. Factors such as the use of corticosteroids and delayed diagnosis were noted to adversely affect the prognosis. This case and this systematic review underscores the potential for non-surgical management options in severe fungal keratitis.

Abstract Timely and effective diagnosis of fungal keratitis (FK) is necessary for suitable treatment and avoiding irreversible vision loss for patients. In vivo confocal microscopy (IVCM) has been widely adopted to guide the FK diagnosis. We present a deep learning framework for diagnosing fungal keratitis using IVCM images to assist ophthalmologists. Inspired by the real diagnostic process, our method employs a two-stage deep architecture for diagnostic predictions based on both image-level and sequence-level information. To the best of our knowledge, we collected the largest dataset with 96,632 IVCM images in total with expert labeling to train and evaluate our method. The specificity and sensitivity of our method in diagnosing FK on the unseen test set achieved 96.65% and 97.57%, comparable or better than experienced ophthalmologists. The network can provide image-level, sequence-level and patient-level diagnostic suggestions to physicians. The results show great promise for assisting ophthalmologists in FK diagnosis.

Background: Infectious keratitis can be caused by bacteria, fungi, and viruses. Fungi are a common pathogen, especially in developing countries like India, Nepal, and Bangladesh where the prevalence ranges from 20% to 60%. In Vietnam, fungal keratitis accounted for the highest number of keratitis cases in a study conducted at the central eye hospital over a 5-year period (57%). Therefore, it is necessary to collect specific background information connected to the types of fungal keratitis in corneal ulcer cases in this region. Aims and Objectives: The aim of this study was to investigate the prevalence of fungal keratitis and the epidemiological features in 216 cases of fungal keratitis out of a total of 240 cases of infectious keratitis. Materials and Methods: This retrospective study collected secondary data from medical records of 240 inpatients with infectious keratitis who were treated at the ophthalmology hospital in Thai Binh, Vietnam, from January 01st, 2021 to June 30th, 2022. Patients with a positive fungal-directed smear were analyzed in detail for the type of fungus isolated, sociodemographic data, predisposing risk factors, prior treatment modalities, and laboratory results for the distribution pattern of fungus species. Results: Among the 240 cases, 126 (52.5%) were diagnosed with fungal keratitis by direct microscopic examination. Culture results showed the highest rate of Fusarium spp. (43.3%). The age group of 41–60 years was most commonly involved (40.5%). Males were more affected by fungal keratitis than females, (53.2% compared to 46.8%), with farmers being the most common occupation correlated with fungal keratitis (55.6%). The rate of fungal keratitis patients due to agricultural injuries was the highest compared to other risks (47.6%) and most patients self-medicated before going to the hospital, with many not knowing or remembering what medications they had taken (52.4%). Conclusion: The study revealed a high rate of fungal keratitis among the total of infectious keratitis cases in Thai Binh, Vietnam. Fusarium spp. was the most commonly isolated fungi. The study also highlighted the impact of agricultural injuries on fungal keratitis, especially in regions like Thai Binh.

AIM: To investigate the protective effect of eugenol against Fusarium solani(F.solani)-induced fungal keratitis(FK)in mice and to preliminarily explore possible underlying mechanisms.METHODS: A modified epifluorescence microscopy method was used to prepare the FK mouse model. An equal amount of DMSO(0.05%)was applied to the conjunctiva of the right eye of rats in the dimethyl sulfoxide(DMSO)group. The eugenol group was prepared by applying eugenol(160 μg/mL)to the conjunctival sac of the right eye of mice. The insulin-like growth factor-1(IGF-1)group was coated with the PI3K/AKT pathway activator IGF-1(10 nmol/mL)in the conjunctival sac of the right eye in addition to the administration of eugenol. The corneal morphology was observed under a slit-lamp microscope on days 1, 3, and 5 of inoculation with F.solani suspension, respectively. Hematoxylin eosin(HE)staining was used to assess corneal histopathological damage. The bacterial load of corneal tissue was determined. Enzyme-linked immunosorbent assay and Western blot were used to analyze the levels of inflammatory mediators interleukin-6(IL-6)and interleukin-1β(IL-1β)and the expression of PI3K/AKT pathway proteins.RESULTS: Eugenol treatment improved the morphological symptoms of keratitis and inflammatory response in FK mice, and reduced corneal pathologic tissue damage and fungal load. At 3 d after F.solani infection, corneal tissue IL-6 levels were significantly higher and IL-1β levels were significantly lower in the eugenol group compared with the DMSO group(both P

Christine K Kim,1 Melisa Z Karslioglu,1 Sharon H Zhao,2 Olivia L Lee1 1Gavin Herbert Eye Institute, University of California, Irvine School of Medicine, Irvine, CA, USA; 2Feinberg School of Medicine, Northwestern University, Chicago, IL, USACorrespondence: Olivia L Lee, Gavin Herbert Eye Institute, University of California Irvine School of Medicine, 850 Health Sciences Road, Irvine, CA, 92617, USA, Tel +1 949 824 0573, Email leeol@hs.uci.eduAbstract: Infectious keratitis (IK) represents a significant global health concern, ranking as the fifth leading cause of blindness worldwide despite being largely preventable and treatable. Elderly populations are particularly susceptible due to age-related changes in immune response and corneal structure. However, research on IK in this demographic remains scarce. Age-related alterations such as increased permeability and reduced endothelial cell density further compound susceptibility to infection and hinder healing mechanisms. Additionally, inflammaging, characterized by chronic inflammation that develops with advanced age, disrupts the ocular immune balance, potentially exacerbating IK and other age-related eye diseases. Understanding these mechanisms is paramount for enhancing IK management, especially in elderly patients. This review comprehensively assesses risk factors, clinical characteristics, and management strategies for bacterial, viral, fungal, and acanthamoeba keratitis in the elderly population, offering crucial insights for effective intervention.Keywords: aging, inflammaging, bacterial keratitis, viral keratitis, fungal keratitis, acanthamoeba keratitis

Abstract Background Infectious keratitis, a significant contributor to blindness, with fungal keratitis accounting for nearly half of cases, poses a formidable diagnostic and therapeutic challenge due to its delayed clinical presentation, prolonged culture times, and the limited availability of effective antifungal medications. Furthermore, infections caused by rare fungal strains warrant equal attention in the management of this condition. Case presentation A case of fungal keratitis was presented, where corneal scraping material culture yielded pink colonies. Lactophenol cotton blue staining revealed distinctive spore formation consistent with the Fusarium species. Further analysis using Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) identified the causative agent as Fusarium proliferatum. However, definitive diagnosis of Pseudonectria foliicola infection was confirmed through ITS sequencing. The patient’s recovery was achieved with a combination therapy of voriconazole eye drops and itraconazole systemic treatment. Conclusion Pseudonectria foliicola is a plant pathogenic bacterium that has never been reported in human infections before. Therefore, ophthalmologists should consider Pseudonectria foliicola as a possible cause of fungal keratitis, as early identification and timely treatment can help improve vision in most eyes.

CONTEXT: Microbial keratitis is a potentially vision-threatening emergency that demands prompt diagnosis and treatment to ensure better vision recovery. Empirical use of broad-spectrum antimicrobial therapies is often the primary treatment modality, which is then tailored according to clinical response, cultured organisms, and their sensitivities. Since the spectrum of microbial agents associated with corneal ulcers is wide and varies from one geographical location to another, it is imperative that local microbial trends and susceptibility patterns are analyzed to enable better care in the management of these patients. AIMS: The aim of the study was to report the microbiological profile and in vitro drug susceptibility patterns of bacterial isolates obtained from patients with microbial keratitis in a single tertiary center in Andhra Pradesh over 12 years. METHODS: Microbiology records of culture-positive microbial keratitis that underwent a diagnostic corneal scraping and cultures from the years 2010 to 2021 were reviewed. Trends in bacterial and fungal etiology along with the antibiotic susceptibility profile of bacteria were analyzed. STATISTICAL ANALYSIS USED: Frequency distribution was obtained, and percentages were calculated. RESULTS: Of the 8529 microbial keratitis samples, 3581 corneal scrapings were culture positive which included Gram-positive bacteria (1054/3581, 29.4%), Gram-negative bacteria (476/3581, 13.2%), fungi (2051/3581, 57.2%), and parasites (369/3581, 10.3%). The most common fungal isolate was Fusarium species (557/1748, 31.8%) followed by Aspergillus flavus (495/1748, 28.3%). Similarly, the most common Gram-positive bacteria included Streptococcus pneumoniae (297/891, 33.3%) and Staphylococcus species (213/891, 23.9%), and the most common Gram-negative bacteria was Pseudomonas aeruginosa (294/403, 72.9%). Overall susceptibility patterns showed that Gram-positive bacteria were susceptible to vancomycin (92%), cefazolin (88%), and chloramphenicol (86%), while Gram-negative bacteria were most susceptible to gentamicin and amikacin (81%). The susceptibility to amikacin and gentamicin increased significantly from 71% in 2010 to 92% in 2021 and 74% in 2010 to 92% in 2021, respectively. In comparison, the susceptibility of fluoroquinolones for both Gram-positive and Gram-negative bacteria did not show any significant change over the study period. CONCLUSIONS: The prevalence of fungal and bacterial keratitis has remained unchanged over the years. This study reinforced that fluoroquinolones and vancomycin continue to be good empiric therapies for treating bacterial keratitis in Andhra Pradesh. [ABSTRACT FROM AUTHOR]

Background/Aims: To determine the clinical features, predisposing factors, and management of infectious keratitis caused by Candida spp. Methods: Retrospective chart review. Results: The medical records of 52 patients (54 eyes) with Candida keratitis were available for statistical analysis. Thinning of the corneal stroma was identified in 34 eyes (63.0%), and corneal perforation occurred in 16 eyes (29.6%). Corneal thinning and perforation were more common in Candida albicans compared with non-albicans (P-val <.001, P =.09, respectively). The most common predisposing factors for Candida keratitis were topical steroid use (21 patients, 40.4%), previous corneal transplantation (17 patients, 32.7%), and preexisting ocular surface disease (15 patients, 28.8%). Fourteen eyes (25.9%) required cyanoacrylate glue application and 10 eyes (18.5%) underwent therapeutic penetrating keratoplasty (TPK). Conclusion: Local immunosuppression and ocular surface disease play an important role in Candida keratitis. C. albicans appears to be more invasive compared with non-albicans spp. [ABSTRACT FROM AUTHOR]

Timely and effective diagnosis of fungal keratitis (FK) is necessary for suitable treatment and avoiding irreversible vision loss for patients. In vivo confocal microscopy (IVCM) has been widely adopted to guide the FK diagnosis. We present a deep learning framework for diagnosing fungal keratitis using IVCM images to assist ophthalmologists. Inspired by the real diagnostic process, our method employs a two-stage deep architecture for diagnostic predictions based on both image-level and sequence-level information. To the best of our knowledge, we collected the largest dataset with 96,632 IVCM images in total with expert labeling to train and evaluate our method. The specificity and sensitivity of our method in diagnosing FK on the unseen test set achieved 96.65% and 97.57%, comparable or better than experienced ophthalmologists. The network can provide image-level, sequence-level and patient-level diagnostic suggestions to physicians. The results show great promise for assisting ophthalmologists in FK diagnosis. [ABSTRACT FROM AUTHOR]

Backroud: Keratitis caused by Lasiodiplodia theobromae is rare and typically associated with a poor prognosis. Current literature lacks sufficient evidence on effective management of patients with this condition. Case presentation: A 74-year-old former agricultural worker presented with a red right eye, discomfort, and decreased visual acuity, progressing over three days without treatment. Examination revealed type 2 diabetes and a non-perforating, spiculated corneal abscess with a hypopyon in the right eye. Initial treatment included a triple antibiotic therapy and supportive care. Direct mycological examination identified numerous septate mycelial filaments. Antifungal treatment with natamycin and voriconazole, both topically and orally, was initiated. Cultures confirmed Lasiodiplodia theobromae. The patient showed significant improvement. Treatment continued for eight weeks, with a final visual acuity of 20/50 due to a stromal scar. Conclusion: An extensive literature review conducted in November 2023, using databases such as PubMed and Google Scholar with the keywords "lasiodiplodia" and "keratitis" yielded no previous cases of this specific condition being managed solely with the combined use of natamycin and voriconazole. This antifungal combination is commonly included in most management protocols for fungal keratitis. Factors such as the use of corticosteroids and delayed diagnosis were noted to adversely affect the prognosis. This case and this systematic review underscores the potential for non-surgical management options in severe fungal keratitis. [ABSTRACT FROM AUTHOR]

Fungal keratitis is a severe corneal infection characterized by suppurative and ulcerative lesions. Aspergillus fumigatus is a common cause of fungal keratitis. Antifungal drugs, such as natamycin, are currently the first-line treatment for fungal keratitis, but their ineffectiveness leads to blindness and perforation. Additionally, the development of fungal resistance makes treating fungal keratitis significantly more challenging. The present study used platelet-derived biomaterial (PDB) to manage A. fumigatus keratitis in the animal model. Freezing and thawing processes were used to prepare PDB, and then A. fumigatus keratitis was induced in the mice. Topical administration of PDB, natamycin, and plasma was performed; quantitative real-time PCR (qPCR) and histopathologic examination (HE) were used to assess the inhibitory effect of the mentioned compounds against fungal keratitis. The qPCR results showed that PDB significantly decreased the count of A. fumigatus compared to the control group (P-value ≤ 5). Natamycin also remarkably reduced the count of fungi in comparison to the untreated animal, but its inhibitory effect was not better than PDB (P-value > 5). The findings of HE also demonstrated that treatment with PDB and natamycin decreased the fungal loads in the corneal tissue. However, plasma did not show a significant inhibitory effect against A. fumigatus. PDB is intrinsically safe and free of any infections or allergic responses; additionally, this compound has a potential role in decreasing the burden of A. fumigatus and treating fungal keratitis. Therefore, scientists should consider PDB an applicable approach to managing fungal keratitis and an alternative to conventional antifungal agents. [ABSTRACT FROM AUTHOR]

Fungal keratitis is a rare yet severe infection of the cornea. Fungal species distribution depends on the climate and socioeconomic status and can show regional variation. This retrospective single-center study was conducted at a tertiary eye care center and the collaborating Institute of Medical Microbiology in Switzerland. On investigating all fungal-positive corneal scrapings and contact lens assessments of patients with keratitis from January 2012 to December 2023, 206 patients were identified, of which 113 (54.9%) were female. The median age was 38 (IQR 29.8, [18–93]), and 154 (74.8%) applied contact lenses. The most commonly found pathogen was Candida spp., followed by Fusarium spp. Molds were 1.8 times more common than yeasts. Linear regression showed no significant increase or decrease in the infection rate over time (p = 0.5). In addition, 10 patients (4.9%) were found to have coinfections with Acanthamoeba, 11 (5.3%) with HSV-1, none with HSV-2, and 4 (1.9%) with VZV. This study provides a long-term overview of fungal-positive corneal scrapings and contact lens specimens of patients with fungal keratitis. Based on our results, coinfections with Acanthamoeba, HSV, and VZV are frequent, especially in patients wearing contact lenses. Thus, wearing contact lenses may facilitate coinfection in fungal keratitis. [ABSTRACT FROM AUTHOR]

Microbial keratitis (MK) is the fourth leading cause of blindness globally, imposing a substantial burden on the healthcare system. This study aims to determine the cost composition of MK patients and explore factors influencing these expenses. We analyzed the demographics, clinical features, and costs of 602 MK patients treated at Beijing Tongren Hospital from June 2021 to October 2023. The analysis revealed the average total cost of treating MK was USD 1646.8, with a median of USD 550.3 (IQR: 333.3–1239.1). Patients with Acanthamoeba keratitis (AK) incurred the highest median total costs at USD 706.2 (IQR: 399.2–3370.2). Additionally, AK patients faced the highest costs for ophthalmic exams and laboratory tests (both p < 0.001), while patients with fungal keratitis (FK) and viral keratitis (VK) experienced higher medication costs. Costs varied significantly with the severity of MK, especially for outpatients at severity level 4, which was markedly higher than levels 1–3 (USD 1520.1 vs. USD 401.0, p < 0.001). Delayed presentation also resulted in increased costs (USD 385.2 vs. USD 600.3, p < 0.001). Our study highlights the financial burden associated with MK treatment and underscores the importance of timely and accurate diagnosis and intervention. [ABSTRACT FROM AUTHOR]

Topical drug delivery employing drug nanocarriers has shown prominent results in treating topical ailments, especially those confined to the skin and eyes. Conventional topical formulations persist with drug and disease‐related challenges during treatment. Various nanotechnology‐driven approaches have been adopted to mitigate the issues associated with conventional formulations. Among these, cubosomes have shown potential applications owing to their liquid crystalline structure, which aids in bioadhesion, retention, sustained release, and loading hydrophilic and hydrophobic moieties. The phase transition behavior of glyceryl monooleate, the concentration of stabilizers, and critical packing parameters are crucial parameters that affect the formation of cubosomes. Microfluidics‐based approaches constitute a recent advance in technologies for generating stable cubosomes. This review covers the recent topical applications of cubosomes for treating skin (psoriasis, skin cancer, cutaneous candidiasis, acne, and alopecia) and eye (fungal keratitis, glaucoma, conjunctivitis, and uveitis) diseases. The article summarizes the manufacturing and biological challenges (skin and ocular barriers) that must be considered and encountered for successful clinical outcomes. The patented products are successful examples of technological advancements within cosmeceuticals that support various topical applications with cubosomes in the pharmaceutical field. [ABSTRACT FROM AUTHOR]

The main cause of corneal blindness worldwide is keratitis, especially the infectious form caused by bacteria, fungi, viruses, and Acanthamoeba. The key to effective management of infectious keratitis hinges on prompt and precise diagnosis. Nevertheless, the current gold standard, such as cultures of corneal scrapings, remains time-consuming and frequently yields false-negative results. Here, using 23,055 slit-lamp images collected from 12 clinical centers nationwide, this study constructed a clinically feasible deep learning system, DeepIK, that could emulate the diagnostic process of a human expert to identify and differentiate bacterial, fungal, viral, amebic, and noninfectious keratitis. DeepIK exhibited remarkable performance in internal, external, and prospective datasets (all areas under the receiver operating characteristic curves > 0.96) and outperformed three other state-of-the-art algorithms (DenseNet121, InceptionResNetV2, and Swin-Transformer). Our study indicates that DeepIK possesses the capability to assist ophthalmologists in accurately and swiftly identifying various infectious keratitis types from slit-lamp images, thereby facilitating timely and targeted treatment. [ABSTRACT FROM AUTHOR]

A 25-year-old Caucasic female was referred to our clinic after suffering from infectious keratitis in the right eye for a month. The patient was a contact lens user and had no history of ocular trauma. Furthermore, the patient did not report any relevant antecedent. The main complaint was intense photophobia and pain. Infectious keratitis remains one of the main complications of contact lens wear and can become a therapeutic challenge in some patients. Although the most frequent causal agent is bacterial, other causes such as herpes virus, Acanthamoeba or fungi should be considered when antimicrobial therapy does not work as expected clinically. Fungal keratitis normally appears on previously damaged corneas, but it can also develop in contact lens wearers. Beauveria bassiana is an unusual pathogen which has been diagnosed more frequently lately per the clinical reports in the last 30 years, so it can be included in the diagnostic scheme when a fungal keratitis is suspected. In clinical management, AS-OCT may be a functional tool to assess the evolution and monitor the response to microbial agents and surgery. Although more studies are needed, some characteristic features have been described and can help to diagnose a fungal keratitis against other infections. AS-OCT can also play an important role in monitoring the corneal scarring after the keratitis episode, and it may be useful to plan post-infection therapy for visual rehabilitation. [ABSTRACT FROM AUTHOR]

To describe the first case of Pythium insidiosum keratitis masquerading as dematiaceous fungal keratitis in a seropositive male. A 44-year-old seropositive male previously treated for acute retinal necrosis presented with pain and defective vision in the right eye following a mud injury 5 days back. Presenting visual acuity was hand movements close to the face. Ocular examination revealed a 7 × 7 mm dense, greyish-white mid stromal infiltrate with pigmentation and few tentacles. The clinical diagnosis suggested fungal keratitis. Corneal scraping on 10% KOH and Gram stain revealed slender, aseptate hyaline hyphae. Before culture results, the patient was treated with topical 5% natamycin and 1% voriconazole, but the infiltrate progressed. Culture on 5% sheep blood agar revealed white fluffy, submerged, shiny, and appressed colonies, and Pythium insidiosum was confirmed by zoospore formation. The patient was further managed with topical linezolid 0.2% hourly, azithromycin 1% hourly, and adjuvant drugs. This is an uncommon presentation of Pythium keratitis masquerading as dematiaceous fungal keratitis in an immunocompromised male. [ABSTRACT FROM AUTHOR]

The application of ketoconazole (KET) in ocular drug delivery is restricted by its poor aqueous solubility though its broad-spectrum antifungal activity. The aim of this study is to develop an ion-sensitive in situ gel (ISG) of KET to promote its ocular bioavailability in topical application. The solubility of KET in water was increased by complexation with hydroxypropyl-β-cyclodextrin (HPβCD), then KET-HPβCD inclusion complex (KET-IC) was fabricated into an ion-sensitive ISG triggered by sodium alginate (SA). The in vitro drug release and antifungal activities investigations demonstrated that the KET-IC-ISG formulation increased drug release and anti-fungal activities compared to pure KET. The ex vivo rabbit corneal permeation studied demonstrated higher permeability of KET-IC-ISG formulation (Papp of (6.34 [Formula: see text]0.21) [Formula: see text]10−4 cm/h) than pure KET (Papp of (3.09 [Formula: see text] 0.09) [Formula: see text]10−4 cm/h). The cytotoxicity assay and the ocular irritation study in rabbits confirmed the KET-IC-ISG safety and well tolerance. The ocular pharmacokinetics of KET in rabbits was investigated and the results showed that the KET-IC-ISG increased its bioavailability in cornea by 47-fold. In conclusion, the KET-IC-ISG system promoted the precorneal retention, the ocular drug bioavailability and the developed formulation is a potential strategy to treat mycotic keratitis.

ObjectiveThe fungal unfolded protein response consists of a two-component relay in which the ER-bound sensor, IreA, splices and activates the mRNA of the transcription factor, HacA. Previously, we demonstrated that hacA is essential for Aspergillus fumigatus virulence in a murine model of fungal keratitis (FK), suggesting the pathway could serve as a therapeutic target. Here we investigate the antifungal properties of known inhibitors of the mammalian Ire1 protein both in vitro and in a treatment model of FK.MethodsThe antifungal activity of Ire1 inhibitors was tested against conidia of several A. fumigatus isolates by a broth microdilution assay and against fungal biofilm by XTT reduction. The influence of 4μ8C on hacA mRNA splicing in A. fumigatus was assessed through gel electrophoresis and qRT-PCR of UPR regulatory genes. The toxicity and antifungal profile of 4μ8C in the cornea was assessed by applying drops to uninfected or A. fumigatus-infected corneas 3 times daily starting 4 hours post-inoculation. Corneas were evaluated daily through slit-lamp imaging and optical coherence tomography, or at endpoint through histology or fungal burden quantification via colony forming units.ResultsAmong six Ire1 inhibitors screened, the endonuclease inhibitor 4μ8C displayed the strongest antifungal profile with an apparent fungicidal action. The compound both blocked conidial germination and hyphal metabolism of A. fumigatus Af293 in the same concentration range that blocked hacA splicing and UPR gene induction (60-120 µM). Topical treatment of sham-inoculated corneas with 0.5 and 2.5 mM 4μ8C did not impact corneal clarity, but did transiently inhibit epithelialization of corneal ulcers. Relative to vehicle-treated Af293-infected corneas, treatment with 0.5 and 2.5 mM drug resulted in a 50% and >90% reduction in fungal load, respectively, the latter of which corresponded to an absence of clinical signs of infection or corneal pathology.ConclusionThe in vitro data suggest that 4μ8C displays antifungal activity against A. fumigatus through the specific inhibition of IreA. Topical application of the compound to the murine cornea can furthermore block the establishment of infection, suggesting this class of drugs can be developed as novel antifungals that improve visual outcomes in FK patients.

Liuyang Hu,1 Qi Chen,2 Xingchun Chen1 1Department of Laboratory Medicine, The People’s Hospital of Guangxi Zhuang Autonomous Region, Guangxi Academy of Medical Sciences, Nanning, 530016, People’s Republic of China; 2Department of Ophthalmology, The People’s Hospital of Guangxi Zhuang Autonomous Region, Guangxi Academy of Medical Sciences, Nanning, 530016, People’s Republic of ChinaCorrespondence: Xingchun Chen, Department of Laboratory Medicine, The People’s Hospital of Guangxi Zhuang Autonomous Region, Guangxi Academy of Medical Sciences, Nanning, 530016, People’s Republic of China, Email 369609020@qq.comAbstract: 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.Keywords: Humicola pulvericola, keratitis, itraconazole, fungal infection, antifungal drugs

Introduction: Ophthalmological conditions in international travelers may be associated with low mortality but high morbidity. Eye involvement in travelers is less frequently reported than febrile, gastrointestinal and respiratory infections, but data probably represent a degree of under-notification. Methods: an extensive narrative review of the main viral, bacterial, fungal and parasitic infections affecting the eye in travelers was performed. Main findings: Common respiratory tract viral infections may cause ocular complications in travelers, human influenza viruses have been associated with conjunctivitis and emerging avian influenza subtypes may also affect the eye. Vector-borne viral infections may affect travelers, usually with systemic symptoms, but eye disease may be the first presenting feature. A spectrum of manifestations have been described with dengue, chikungunya and Zika infections, including conjunctivitis, anterior uveitis, posterior uveitis with chorioretinitis and macular involvement. Staphylococcus spp, Streptococcus spp, and Pseudomonas spp (especially associated with use of contact lenses) are common causes of keratitis, however, resistance patterns to antimicrobials might vary depending on area of travel. Less frequent infections, such as Burkholderia pseudomallei, associated with environmental exposure, and Bartonella spp. may rarely present with ophthalmological involvement in travelers. Fungal ocular infections, especially after ocular trauma caused by plants and contact lens use, should be considered in patients with stromal keratitis not improving with antibiotic eye drops. Parasitic eye infections tend to occur in tropical areas, but some, such as acanthamoebic keratitis or Toxoplasma spp retinitis, are found worldwide. Increasing exposure to animals, undercooked food consumption or poor hygiene during international travels might be leading to the emergence of certain parasitic eye diseases. Conclusions: Clinical features, with identification of risk factors and geographical region of exposure, can assist in the definitive diagnosis of imported ophthalmological infections. Management of imported eye infections requires a multi-disciplinary approach involving ophthalmologists, travel medicine/infectious diseases physicians and other specialists.

* This report details a rare case of corneal infection caused by Medicopsis romeroi, highlighting clinical presentation, diagnostic methods, treatment, and outcome. An early adolescence male, after recent corneal tear repair, presented acute eye pain, redness, and decreased vision for 1 day. He underwent corneal tear repair elsewhere post vegetative matter-related swimming injury. Ophthalmic examination revealed a 2.5*3.3mm ulcer around sutures. Corneal scrapings enabled microscopy and culture. With lesion worsening, tissue adhesive (TA) and bandage contact lens (BCL) were applied. Fungal culture identified Medicopsis romeroi. Patient's history, clinical course, and treatment were documented. Microscopy unveiled fungal hyphae, later confirmed as Medicopsis romeroi. Treatment included topical/systemic antifungals. Post-TA + BCL, significant improvement followed, with re-epithelialization, scarring. This report underscores the importance of considering rare fungal pathogens like Medicopsis romeroi in cases of corneal ulcers, especially in individuals with unusual risk factors. Timely diagnosis through microscopy and fungal culture, coupled with tailored antifungal treatment led to successful management and favorable patient outcomes. This case also emphasizes the significance of vigilant clinical observation, precise laboratory analysis, and multidisciplinary collaboration between ophthalmologists and microbiologists in managing atypical ocular infections.

Introduction: Antimicrobial resistance in microbial keratitis has not been previously explored in Alexandria. We aim to recommend effective therapies through identification of etiological agents, determination of antimicrobial susceptibilities, and comparing outcomes of empiric topical antimicrobials. Methods: In this 2022 prospective cohort conducted in Alexandria Main University Hospital cornea clinic, antimicrobial susceptibilities of isolated microorganisms from corneal scrapings were detected and antibiograms were developed. Bacterial (BK), fungal (FK), or mixed fungal/bacterial keratitis (MFBK) patients on empiric regimens were compared for ulcer healing, time-to-epithelialization, best-corrected visual acuity, interventions, and complications. Results: The prevalent microorganisms in 93 positive-cultures were coagulase-negative staphylococci (CoNS, 30.1%), Pseudomonas aeruginosa (14%), and Aspergillus spp. (12.9%). CoNS were susceptible to vancomycin (VAN, 100%) and moxifloxacin (MOX, 90.9%). Gram-negative bacteria showed more susceptibility to gatifloxacin (90.9%) than MOX (57.1%), and to gentamicin (GEN, 44.4%) than ceftazidime (CAZ, 11.8%). Methicillin-resistance reached 23.9% among Gram-positive bacteria. Fungi exhibited 10% resistance to voriconazole (VRC). Percentages of healed ulcers in 49 BK patients using GEN + VAN, CAZ + VAN and MOX were 85.7%, 44.4%, and 64.5%, respectively (p = 0.259). Their median time-to-epithelialization reached 21, 30, and 30 days, respectively (log-rank p = 0.020). In 51 FK patients, more ulcers (88.9%) healed with natamycin (NT) + VRC combination compared to VRC (39.1%) or NT (52.6%) (p = 0.036). Their median time-to-epithelialization was 65, 60, and 22 days, respectively (log-rank p < 0.001). The VRC group required more interventions (60.9%) than NT + VRC-treated group (11.1%) (p = 0.018). In 23 MFBK patients, none healed using NT + CAZ + VAN, while 50% healed using VRC + CAZ + VAN (p = 0.052). Regimens had comparable visual outcomes and complications. Conclusion: Based on the higher detected susceptibility, we recommend empiric MOX in suspected Gram-positive BK, gatifloxacin in Gram-negative BK, and GEN + VAN in severe BK. Due to better outcomes, we recommend NT + VRC in severe FK. Trial registration: ClinicalTrials.gov identifier, NCT05655689. Registered December 19, 2022– Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT05655689?cond=NCT05655689.&draw=2&rank=1 [ABSTRACT FROM AUTHOR]

Objectives: To investigate the clinical efficacy of cyclosporin (CYSP) and natamycin (NAT) as a combination therapy in patients with fungal keratitis. Methods: This is a retrospective study. A total of 64 patients (64 eyes) with fungal keratitis treated by Baoding No.1 Central Hospital between December 2018 and May 2022 according to their treatment methods were divided into a monotherapy (MT) group receiving NAT eye drops solely and a combination therapy (CT) group given CYSP eye drops in addition to the exact treatment provided for the MT group. The clinical responses, visual acuity changes, severity of eye symptoms, and adverse reactions were compared between the two groups. Results: At two and four weeks post-treatment, the CT group had an overall response rate (ORR) significantly higher than that of the MT group (P< 0.05, respectively); both groups showed improved visual acuity and eye symptoms compared with the pre-treatment condition, and these improvements were more pronounced in the CT group (P < 0.05, respectively). Compared with the MT group, the CT group experienced a significantly shorter duration of eye symptoms (P < 0.05). The adverse reaction rate(ARR) was 9.38% in the CT group and 6.25% in the MT group, and the difference was not significant (P > 0.05). Conclusion: Using CYSP and NAT as a combination therapy for fungal keratitis can substantially heighten the therapeutic effects, promote visual acuity recovery, and induce rapid remission of eye symptoms without increasing the risk of adverse reactions. [ABSTRACT FROM AUTHOR]

Background: Fungal keratitis is a severe eye infection that can result in blindness and visual impairment, particularly in developing countries. Fusarium spp. are the primary causative agents of this condition. Diagnosis of Fusarium keratitis (FK) is challenging, and delayed treatment can lead to serious complications. However, there is limited epidemiological data on FK, especially in tropical areas. Objectives: This study aimed to describe the clinical, laboratorial and epidemiological characteristics of FK in a tropical semi‐arid region of Brazil. Patients/Methods: Adult patients with laboratory‐confirmed FK diagnosed between October 2019 and March 2022 were evaluated. Fusarium isolates were characterized at molecular level and evaluated regarding antifungal susceptibility. Results: A total of 226 clinical samples from patients suspected of keratitis were evaluated; fungal growth was detected in 50 samples (22.12%); out of which 42 were suggestive of Fusarium spp. (84%). Molecular analysis of a randomly selected set of 27 isolates identified F. solani species complex (n = 14); F. fujikuroi sensu lato (n = 6) and F. dimerum sensu lato (n = 7); a total of 10 haplotypes were identified among the strains. All but one Fusarium strains were inhibited by amphotericin B, natamycin and fluconazole. Most patients were male (71.42%; 30 out of 42), aged from 27 to 73 years old. Trauma was the most important risk factor for FK (40.47%; 17 out of 42). Patients were treated with antifungals, corticoids and antibiotics; keratoplasty and eye enucleation were also performed. Conclusions: The study provided insights into the characteristics of FK in tropical regions and emphasized the importance of enhanced surveillance and management strategies. [ABSTRACT FROM AUTHOR]

This article explores the burgeoning role of cold atmospheric plasma (CAP) in ophthalmology. The versatile nature of CAP has transformed various facets of eye care, offering novel possibilities across different clinical domains. From sterilizing surgical instruments without compromising their integrity to effectively managing challenging corneal diseases like microbial keratitis and fungal infections, CAP has shown promising results. Moreover, its potential role in promoting corneal wound healing, facilitating corneal transplants, and enhancing outcomes in cataract surgeries deserves attention. The low-tension plasma blade (ie, the Fugo blade™, Medisurg Ltd. Norristown, PA), a controlled and precise form of CAP, has emerged as a game-changer in delicate eye surgeries. Its unmatched precision, minimal tissue damage, and surgeon-friendly nature have revolutionized ophthalmic procedures, including ptosis correction, dry eye treatment, and conjunctival cyst ablation. Despite conflicting findings on the efficacy of this technology in certain aspects, the extensive body of research on CAP underscores its potential for wider ophthalmic integration. Further investigation, including human trials, is crucial for understanding the in vivo safety profile of CAP for ophthalmic applications and optimizing its use, potentially revolutionizing ocular disease management and improving patient outcomes. [ABSTRACT FROM AUTHOR]

This study aims to report the efficacy of a combined intrastromal injection in optimizing the outcome of severe mycotic keratitis. Herein, we report a case series of 20 consecutive patients with positive fungal cultures not responding to topical antifungal treatment. Patients received cycles of intrastromal injections of voriconazole (50 µg/0.1 mL) and amphotericin B (2.5 µg/0.1 mL); all patients continued their topical antifungal therapy. The organisms isolated were Fusarium (n = 5), Aspergillus (n = 4), Candida (n = 4), Rhodotorula (n = 2), Penicillium (n = 2), Alternaria (n = 1), Bipolaris (n = 1), and Curvularia (n = 1). The size of the infiltrate varied from 6.5 to 1.5 mm. At presentation, the best corrected visual acuity (BCVA, namely, the best visual acuity achieved with glasses, if needed) was less than 20/400 in all patients, improving to better than 20/400 in eleven patients. Seven patients required surgical intervention; four of them underwent penetrating keratoplasty (PK) à chaud one month after the first intrastromal injection. Patients who underwent surgery achieved a BCVA of 20/40 or better. Combined intrastromal injections before therapeutic penetrating keratoplasty (TPK) effectively reduced ulcer size and graft diameter, preventing infection recurrence. Our results highlight the efficacy of combined intrastromal injections in optimizing outcomes for severe mycotic keratitis undergoing TPK. [ABSTRACT FROM AUTHOR]

Melanin is an Aspergillus flavus cell wall component that provides chemical and physical protection to the organism. However, the molecular and biological mechanisms modulating melanin-mediated host–pathogen interaction in A. flavus keratitis are not well understood. This work aimed to compare the morphology, surface proteome profile, and virulence of melanized conidia (MC) and non-melanized conidia (NMC) of A. flavus. Kojic acid treatment inhibited melanin synthesis in A. flavus, and the conidial surface protein profile was significantly different in kojic acid-treated non-melanized conidia. Several cell wall-associated proteins and proteins responsible for oxidative stress, carbohydrate, and chitin metabolic pathways were found only in the formic acid extracts of NMC. Scanning electron microscopy (SEM) analysis showed the conidial surface morphology difference between the NMC and MC, indicating the role of melanin in the structural integrity of the conidial cell wall. The levels of calcofluor white staining efficiency were different, but there was no microscopic morphology difference in lactophenol cotton blue staining between MC and NMC. Evaluation of the virulence of MC and NMC in the Galleria mellonella model showed NMC was less virulent compared to MC. Our findings showed that the integrity of the conidial surface is controlled by the melanin layer. The alteration in the surface protein profile indicated that many surface proteins are masked by the melanin layer, and hence, melanin can modulate the host response by preventing the exposure of fungal proteins to the host immune defense system. The G. mellonella virulence assay also confirmed that the NMC were susceptible to host defense as in other Aspergillus pathogens. Key points: • l-DOPA melanin production was inhibited in A. flavus isolates by kojic acid, and for the first time, scanning electron microscopy (SEM) analysis revealed morphological differences between MC and NMC of A. flavus strains • Proteome profile of non-melanized conidia showed more conidial surface proteins and these proteins were mainly involved in the virulence, oxidative stress, and metabolism pathways • Non-melanized conidia of A. flavus strains were shown to be less virulent than melanised conidia in an in vivo virulence experiment with the G. melonella model [ABSTRACT FROM AUTHOR]

Fungal keratitis (FK) is a dangerous corneal infection that is common in tropical and subtropical areas. Its incidence is extremely high, and ocular trauma and contact lenses can lead to FK, but its common treatment such as using topical antifungal eye drop instillation is often less effective because of several drawbacks of the drugs typically used, including limited ocular penetration, high frequency of dosing, poor biocompatibility, and the potential for severe drug reactions. Therefore, the development of novel drug delivery devices for the treatment of FK is urgent. The urgent need for novel drug delivery devices to treat FK has led to the development of several techniques, including nanoparticles (NPs), in situ forming hydrogels, contact lenses, and microneedles (MNs). However, it is important to note that the main mechanisms differ between these techniques. NPs can transport large amounts of drugs and be taken up by cells owing to their large surface area and small size. In situ forming hydrogels can significantly extend the residence time of drugs because of their strong adhesive properties. Contact lenses, with their comfortable shape and drug-carrying capacity, can also act as drug delivery devices. MNs can create channels in the cornea, bypassing its barrier and enhancing drug bioavailability. This article will go over novel medication delivery techniques for treating FK and make a conclusion about their advantages and limitations in anticipation to serve the best option for the individual therapy of FK. [ABSTRACT FROM AUTHOR]

Purpose: This study sought to identify the sources of differential performance and misclassification error among local (Indian) and external (non-Indian) corneal specialists in identifying bacterial and fungal keratitis based on corneal photography. Methods: This study is a secondary analysis of survey data assessing the ability of corneal specialists to identify acute bacterial versus fungal keratitis by using corneal photography. One-hundred images of 100 eyes from 100 patients with acute bacterial or fungal keratitis in South India were previously presented to an international cohort of cornea specialists for interpretation over the span of April to July 2021. Each expert provided a predicted probability that the ulcer was either bacterial or fungal. Using these data, we performed multivariable linear regression to identify factors predictive of expert performance, accounting for primary practice location and surrogate measures to infer local fungal ulcer prevalence, including locality, latitude, and dew point. In addition, Brier score decomposition was used to determine experts' reliability ("calibration") and resolution ("boldness") and were compared between local (Indian) and external (non-Indian) experts. Results: Sixty-six experts from 16 countries participated. Indian practice location was the only independently significant predictor of performance in multivariable linear regression. Resolution among Indian experts was significantly better (0.08) than among non-Indian experts (0.01; P < 0.001), indicating greater confidence in their predictions. There was no significant difference in reliability between the two groups (P = 0.40). Conclusion: Local cornea experts outperformed their international counterparts independent of regional variability in tropical risk factors for fungal keratitis. This may be explained by regional characteristics of infectious ulcers with which local corneal specialists are familiar. [ABSTRACT FROM AUTHOR]

Fungal keratitis (FK) is a vision-threatening infection. We aimed to explore the antifungal and anti-inflammatory effects of pseudolaric acid B (PAB) on FK and the underlying mechanisms involved. Network pharmacology utilized to acquire the potential target genes, and silent information regulator 1 (SIRT1) was consistently downregulated in Gene Expression Omnibus dataset and clinical samples. Molecular docking analysis showed that PAB and SIRT1 had good binding activity. No toxicity was observed in vivo and in vitro with a PAB concentration below 0.3 μM. PAB exerted its antifungal activity by destroying the integrity of hyphae, and alleviated the severity of FK in rats by decreasing clinical scores, fungal burden and inhibiting inflammatory cell infiltration. PAB increased SIRT1 to regulate the crosstalk between nuclear factor erythroid 2-related factor 2 (Nrf2) and nuclear factor kappa-B (NF-κB), decreasing the levels of inflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6; and pattern recognition receptors, C-type lectin domain containing 7A (Dectin-1), lectin-like oxidized low-density lipoprotein receptor 1 (LOX-1), toll like receptor (TLR)-2, and TLR4 both in vivo and in vitro. However, this anti-inflammatory effect of PAB was abolished by the SIRT1 inhibitor EX527. This study provides new evidence that PAB has antifungal and anti-inflammatory effects in FK and may provide a novel therapeutic strategy for the treatment of FK. [ABSTRACT FROM AUTHOR]

Facial burns involving the periorbital region may lead to cicatricial ectropion and lagophthalmos, causing severe exposure keratopathy and eventually blindness if uncorrected. In these patients, it is critical to provide aesthetic and functional surgical correction to protect the ocular surface from chronic desiccation in addition to visual rehabilitation. Conventional methods may not be sufficient to provide visual rehabilitation in complex cases. Scleral lenses can be a multipurpose alternative for these patients. Herein, we present the challenging case of a patient who developed cicatricial lagophthalmos and exposure keratopathy after facial transplantation due to gasoline burns and received a scleral contact lens for visual rehabilitation. [ABSTRACT FROM AUTHOR]

Fungal keratitis is a refractory eye disease that is prone to causing blindness. Fungal virulence and inflammatory responses are two major factors that accelerate the course of fungal keratitis. However, the current antifungal drugs used for treatment usually possess transient residence time on the ocular surface and low bioavailability deficiencies, which limit their therapeutic efficacy. In this work, natamycin (NATA)-loaded mesoporous zinc oxide (Meso-ZnO) was synthesized for treating Aspergillus fumigatus keratitis with excellent drug-loading and sustained drug release capacities. In addition to being a carrier for drug delivery, Meso-ZnO could restrict fungal growth in a concentration-dependent manner, and the transcriptome analysis of fungal hyphae indicated that it inhibited the mycotoxin biosynthesis, oxidoreductase activity and fungal cell wall formation. Meso-ZnO also promoted cell migration and exhibited anti-inflammatory role during fungal infection by promoting the activation of autophagy. In mouse models of fungal keratitis, Meso-ZnO/NATA greatly reduced corneal fungal survival, alleviated tissue inflammatory damage, and reduced neutrophils accumulation and cytokines expression. This study suggests that Meso-ZnO/NATA can be a novel and effective treatment strategy for fungal keratitis. [Display omitted] [ABSTRACT FROM AUTHOR]