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Infectious keratitis is a significant global problem that can lead to corneal blindness and visual impairments. This study aimed to investigate the etiology of infectious bacterial and fungal keratitis, identify the causative pathogens and their antimicrobial resistance patterns, and analyze the risk factors associated with the development of infectious keratitis. The study was observational and retrospective, involving 226 eyes from 223 patients presented at the Ophthalmology Clinic of the County Clinical Emergency Hospital of Craiova, Romania. The inclusion criteria included corneal ulceration/abscess/infiltrate present on slit-lamp examination and positive microbiological sampling for bacteria or fungi. The study found that the most common causes of infectious keratitis were coagulase-negative staphylococci (35.40%), Staphylococcus aureus (11.06%), and Pseudomonas aeruginosa (14.16%). The Gram-positive bacteria showed high resistance rates to penicillin, moderate rates to gentamycin and clindamycin, and low resistance to chinolones. The Gram-negative bacteria were highly resistant to ampicillin and amoxicillin–clavulanic acid, while third-generation cephalosporins, quinolones, and carbapenems were effective. Systemic antibiotics, such as vancomycine, piperacillin–tazobactam, amikacin, and ceftazidime, show promise against keratitis with low resistance rates, whereas carbapenems and topical aminoglycosides had higher resistance, leaving moxifloxacin as a potential topical option for Gram-positive bacteria and Pseudomonas aeruginosa, albeit with resistance concerns for Klebsiella spp. Although fungal keratitis was rare, Fusarium spp. and Candida albicans were the leading fungal pathogens, with incidences of 2.65% and 2.21%, respectively. Candida albicans was broadly susceptible to most antifungals, while Fusarium solani, Curvularia lunata, and Alternaria alternata exhibited resistance to many antifungals. Amphotericin B and caspofungin can be used as systemic antifungals in fungal keratitis. The study also identified risk factors for keratitis such as ocular trauma (65.92%, OR: 2.5), contact lens wear (11.94%, OR: 1.8), and corneal scarring/leukoma (10.17%, OR: 1.6). Keratitis was more frequent in individuals over 60 years old. The findings of this study have implications for the development of effective diagnostic, therapeutic, and preventive strategies for infectious keratitis. [ABSTRACT FROM AUTHOR]

Background: Fungal keratitis (FK) is a kind of infectious keratopathy with a high rate of blindness worldwide. Deoxynivalenol (DON) has been proven to have multiple toxic effects on humans and animals. Objectives: The aim of this study was to explore a possible pathogenic role of DON in FK. Methods: We first made an animal model of FK in New Zealand white rabbits, and then attempted to detect DON in a culture medium in which Fusarium solani had been grown and also in the corneal tissue of the animal model of Fusarium solani keratitis. Next, a model of DON damage in human corneal epithelial cells (HCECs) was constructed to evaluate effects of DON on the activity, migration ability, cell cycle, and apoptosis in the HCECs. Then, putative the toxic damaging effects of DON on rabbit corneal epithelial cells and the impact of the repair cycle were studied. The expression levels of inflammatory factors in the corneas of the animal model and in the model of DON-damaged HCECs were measured. Results: The Fusarium solani strain used in this study appeared to have the potential to produce DON, since DON was detected in the corneal tissue of rabbits which had been inoculated with this Fusarium solani strain. DON was found to alter the morphology of HCECs, to reduce the activity and to inhibit the proliferation and migration of HCECs. DON also induced the apoptosis and S-phase arrest of HCECs. In addition, DON was found to damage rabbit corneal epithelial cells, to prolong the corneal epithelial regeneration cycle, and to be associated with the upregulated expression of inflammatory factors in HCECs and rabbit corneas. Conclusions: DON appears to have a toxic damaging effect on HCECs in FK, and to induce the expression of inflammatory factors, leading to the exacerbation of keratitis and the formation of new blood vessels. Future studies will explore the possibility of developing a test to detect DON in ophthalmic settings to aid the rapid diagnosis of FK, and to develop DON neutralizers and adsorbents which have the potential to improve keratocyte status, inhibit apoptosis, and alleviate inflammation, therein providing new thinking for therapy of clinical FK. [ABSTRACT FROM AUTHOR]

Fungal keratitis is a severely vision-threatening corneal infection, where the prognosis depends on both fungal virulence and host immune defense. Inappropriate host responses can induce substantial inflammatory damage to the cornea. Therefore, in the treatment of fungal keratitis, it is important to concurrently regulate the immune response while efforts are made to eliminate the pathogen. Ebselen is a widely studied organo-selenium compound and has been demonstrated to have antifungal, antibacterial, anti-inflammatory, and oxidative stress-regulatory properties. The effectiveness of ebselen for the treatment of fungal keratitis remains unknown. In this study, ebselen was demonstrated to produce a marked inhibitory effect on Aspergillus fumigatus (A. fumigatus), including spore germination inhibition, mycelial growth reduction, and fungal biofilm disruption. The antifungal activity of ebselen was related to the cell membrane damage caused by thioredoxin (Trx) system inhibition-mediated oxidative stress. On the contrary, ebselen enhanced the antioxidation of Trx system in mammalian cells. Further, ebselen was proven to suppress the expressions of inflammatory mediators (IL-1β, IL-6, TNF-α, COX-2, iNOS, and CCL2) and reduce the production of oxidative stress-associated indicators (ROS, NO, and MDA) in fungi-stimulated RAW264.7 cells. In addition, ebselen regulated PI3K/Akt/Nrf2 and p38 MAPK signaling pathways, which contributed to the improvement of inflammation and oxidative stress. Finally, we verified the therapeutic effect of ebselen on mouse fungal keratitis. Ebselen improved the prognosis and reduced the fungal burden in mouse corneas. Expressions of inflammatory mediators, as well as the infiltration of macrophages and neutrophils in the cornea were also obviously decreased by ebselen. In summary, ebselen exerted therapeutic effects by reducing fungal load and protecting host tissues in fungal keratitis, making it a promising treatment for fungal infections.

Introduction: This case report describes a rare case of fungal keratitis following femtoLASIK. Despite targetted antifungal therapy, this case necessitated an innovative surgical approach to manage an unexpected corneal perforation. Case Presentation: A 35-year-old male presented 3 weeks post-femtoLASIK for myopic astigmatism with discomfort and reduced vision in his right eye. He was diagnosed with fungal keratitis surgery caused by Purpureocillium lilacinum and was treated with a myriad of therapy. Unfortunately, the patient developed corneal perforation during flap lift and flap bed irrigation. An innovative approach involving a tectonic autograft using a viable LASIK flap, followed by prompt penetrating keratoplasty, was utilised. Conclusion: This technique was effective and able to mitigate the progression to an open globe.

Objectives:The aim of the present study was to evaluate any conjunctival metaplastic changes by impression cytology in patients who underwent topical 1% voriconazole treatment for severe fungal keratitis.Materials and Methods:The study was conducted at Ege University Faculty of Medicine, Departments of Ophthalmology and Medical Pathology. Patients who were treated with 1% topical voriconazole for fungal keratitis for at least 3 months were included. The used topical voriconazole treatment was initiated as one drop every hour and was tapered according to clinical improvement in all patients. Treatment was continued 4 times a day for at least 3 months. Impression cytology samples were collected at least 3 months after cessation of topical voriconazole from the affected eyes and from the fellow eyes as a control group. Collected specimens were transferred to the pathology department for evaluation and grading (Nelson’s grading system).Results:The mean age of the patients was 57.68±17.32 years (range, 22-87 years). The impression cytology grade of the inferior bulbar conjunctiva was 1.73±0.77 (range, 0-3) in the study group and 1.19±0.98 (range, 0-3) in the control group (p=0.03). The impression cytology grade of the temporal bulbar conjunctiva was 1.69±0.73 (range, 0-3) in the study group and 1.15±0.88 (range, 0-3) in the control group (p=0.02). The impression cytology grades of the nasal and superior bulbar conjunctiva did not differ statistically (p values 0.13 and 0.17, respectively).Conclusion:Topical voriconazole is an effective broad-spectrum antifungal drug, but it induces conjunctival squamous metaplasia. Clinicians should be aware of this possible side effect of topical voriconazole and should carefully evaluate the conjunctiva of treated patients at each visit to detect possible metaplastic changes.

Abstract Background The aim of this report is to describe the risk factors, clinical course, and characteristics of three cases of Paecilomyces keratitis presenting concurrently within three months in the same location. We used in vivo confocal microscopy and histopathology to corroborate our clinical findings. Observations Three eyes of three elderly patients with culture-proven Paecilomyces keratitis were included in this series. These patients resided within a 15-mile radius and presented to a tertiary care eye institute in Southern California between February and April 2022. All three eyes experienced a prolonged, recalcitrant course with recurrence of keratitis in donor corneal tissue despite antifungal therapy and multiple therapeutic penetrating keratoplasties. In vivo confocal microscopy, histopathology, and microbiologic findings corroborated the diagnosis of fungal keratitis with Paecilomyces. With surgical intervention and extensive medical therapy, all three cases resolved after the addition of oral Posaconazole. Conclusions Paecilomyces is a rare cause of infectious keratitis. Herein we report three similar cases in elderly patients. All had prolonged, recalcitrant infections that required multiple treatment modalities. Our cases, which were supported by in vivo confocal microscopy and histopathology, highlight the importance of timely and aggressive therapy to prevent recurrence.

Ramy Awad,1 Alaa Atef Ghaith,2 Khaled Awad,1 Marina Mamdouh Saad,1 Ahmed Ak Elmassry2 1Department of Ophthalmology, Alexandria General Ophthalmology Hospital, Alexandria, Egypt; 2Department of Ophthalmology, Faculty of Medicine, Alexandria University, Alexandria, EgyptCorrespondence: Ahmed Ak Elmassry, Ophthalmology Department, Faculty of Medicine, Alexandria University, Champollion Street, Al Attarin, Alexandria, Egypt, Tel +2 0122 215 2435, Email ahmad.elmassry@gmail.comAbstract: Fungal keratitis is one of the major causes of microbial keratitis that may lead to corneal blindness. Many problems related to diagnosis and therapy are encountered in fungal keratitis, including difficulty in obtaining laboratory diagnoses and the availability and efficacy of antifungal medications. Intensive and prolonged use of antifungal topical preparations may not be enough. The use of antifungal medications is considered the main treatment for fungal keratitis. It is recommended to start antifungal therapy after confirmation of the clinical diagnosis with a smear or positive cultures. Topical application of antifungal medications is a mainstay for the treatment of fungal keratitis; however, systemic, intra-stromal, or intra-cameral routes may be used. Therapeutic keratoplasty is the main surgical procedure approved for the management of fungal keratitis with good success rate. Intrastromal corneal injection of antifungal medications may result in steady-state drug levels within the corneal tissue and prevent intervals of decreased antifungal drug concentration below its therapeutic level. In cases of severe fungal keratitis with deep stromal infiltration not responding to treatment, intracameral injection of antifungal agents may be effective. Collagen cross-linking has been proposed to be beneficial for cases of fungal keratitis as a stand-alone therapy or as an adjunct to antifungal medications. Although collagen cross-linking has been extensively studied in the past few years, its protocol still needs many modifications to optimize UV fluence levels, irradiation time, and concentration of riboflavin to achieve 100% microbial killing.Keywords: fungal keratitis, keratomycosis, PACK-CXL, antifungal, voriconazole, intracorneal injection, targeted therapy

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.

Objective: The purpose of this study was to report a case of herpes simplex virus-1 (HSV-1) keratitis misdiagnosed as fungal keratitis due to its clinical presentation being similar to that of fungal keratitis, ultimately diagnosed by NGS. Patients and Methods: A 59-year-old male presented with reduced vision in the right eye, combined with a history of trauma with vegetative matter. The corneal ulcer was accompanied with feathery infiltration, satellite lesion, and endothelial plaques. In vivo confocal microscopy (IVCM) showed hyper-reflective linear, thin, and branching interlocking structures. Fungal keratitis was diagnosed. Voriconazole 100 mg orally daily, topical tobramycin and 1% voriconazole were initiated empirically right away. The condition was aggravated and penetrating keratoplasty was performed. Anterior segment optical coherence tomography (AS-OCT) demonstrated the presence of plaques with a clear boundary between plaques and endothelium, resembling the AS-OCT images observed in cases of viral keratitis. Next-generation sequencing (NGS) further detected HSV-1 deoxyribonucleic acid, and no fungal component was found. Antifungal agents were discontinued and antiviral treatments were added. Results: We successfully treated a patient with HSV-1 keratitis who was misdiagnosed due to clinical features and IVCM findings similar to fungal keratitis. The patient's infection was controlled. At 2 years after surgery, the cornea recovered well. Conclusions: HSV-1 keratitis with atypical clinical presentation can be easily misdiagnosed. This case report emphasizes the importance of NGS in diagnosing the pathogens of keratitis. [ABSTRACT FROM AUTHOR]

Purpose: The objective of this study was to investigate the epidemiological characteristics, distribution of isolates, prevailing patterns, and antibiotic susceptibility of bacterial keratitis (BK) in a Tertiary Referral Hospital located in Southwest China. Methods: A retrospective analysis was conducted on 660 cases of bacterial keratitis occurring between January 2015 and December 2022. The demographic data, predisposing factors, microbial findings, and antibiotic sensitivity profiles were examined. Results: Corneal trauma emerged as the most prevalent predisposing factor, accounting for 37.1% of cases. Among these cases, bacterial culture results were positive in 318 cases, 68 species of bacteria were identified. The most common Gram-Positive bacteria isolated overall was the staphylococcus epidermis and the most common Gram-Negative bacteria isolated was Pseudomonas aeruginosa. Methicillin-Resistant Staphylococci accounted for 18.1% of all Gram-Positive bacteria. The detection rate of P. aeruginosa showed an increasing trend over time (Rs=0.738, P=0.037). There was a significant decrease in the percentage of Gram-Negative microorganisms over time (Rs=0.743, P=0.035). The sensitivity of Gram-Positive bacteria to linezolid, vancomycin, tigecycline, quinupristin/ dalfopristin, and rifampicin was over 98%. The sensitivity rates of Gram-Negative bacteria to amikacin, meropenem, piperacillin/tazobactam, cefoperazone sodium/ sulbactam, ceftazidime, and cefepime were all above 85%. In patients with a history of vegetative trauma, the possibility of BK should be taken into account in addition to the focus on fungal keratitis. Conclusion: The microbial composition primarily consists of Gram-Positive cocci and Gram-Negative bacilli. Among the Gram-Positive bacteria, S. epidermidis and Streptococcus pneumoniae are the most frequently encountered, while P. aeruginosa is the predominant Gram-Negative bacteria. To combat Gram-Positive bacteria, vancomycin, linezolid, and rifampicin are considered excellent antimicrobial agents. When targeting Gram-Negative pathogens, third-generation cephalosporins exhibit superior sensitivity compared to first and second-generation counterparts. As an initial empirical treatment for severe cases of bacterial keratitis and those unresponsive to fourthgeneration fluoroquinolones in community settings, the combination therapy of vancomycin and tobramycin is a justifiable approach. Bacterial keratitis can be better managed by understanding the local etiology and antibacterial drug susceptibility patterns. [ABSTRACT FROM AUTHOR]

Introduction: Infectious Keratitis is one of the most common ocular emergencies seen by ophthalmologists. Our aim is to identify the risk factors and clinical features of Acanthamoeba Keratitis (AK). Methods: This retrospective chart review study was conducted at King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia, and included all the microbial keratitis cases, male and female patients of all ages. The main outcome is the differentiation between various microbial keratitis types. Results: We included 134 consecutive eyes of 126 persons. We had 24 cases of acanthamoeba keratitis, 22 bacterial keratitis, 24 fungal keratitis, 32 herpetic keratitis, and 32 bacterial co-infection. Contact lens wear was found in 33 eyes (24.6%). Among acanthamoeba keratitis patients, 73% were ≤ 39 years of age, and 73% were females (P <0.001). Also, in AK cases, epithelial defect was found in all cases (100%), endothelial plaques were found in 18 eyes (69.2%), 12 cases had radial keratoneuritis (46.2%), and ring infiltrate was found in 53.8% of AK cases. Conclusions: We determined the factors that increase the risk of acanthamoeba infection and the clinical characteristics that help distinguish it from other types of microbial keratitis. Our findings suggest that younger females and patients who wear contact lenses are more likely to develop acanthamoeba keratitis. The occurrence of epitheliopathy, ring infiltrate, radial keratoneuritis, and endothelial plaques indicate the possibility of acanthamoeba infection. Promoting education on wearing contact lenses is essential to reduce the risk of acanthamoeba infection, as it is the most significant risk factor for this infection. [ABSTRACT FROM AUTHOR]

Fungal keratitis is the foremost cause of corneal infections worldwide, of which Fusarium spp. is the common etiological agent that causes loss of vision and warrants surgical intervention. An increase in resistance to the available drugs along with severe side effects of the existing antifungals demands for new effective antimycotics. Here, we demonstrate that antimicrobial peptide S100A12 directly binds to the phospholipids of the fungal membrane, disrupts the structural integrity, and induces generation of reactive oxygen species in fungus. In addition, it inhibits biofilm formation by Fusarium spp. and exhibits antifungal property against Fusarium spp. both in vitro and in vivo. Taken together, our results delve into specific effect of S100A12 against Fusarium spp. with an aim to investigate new antifungal compounds to combat fungal keratitis. [ABSTRACT FROM AUTHOR]

The purpose is to assess the efficacy of rose bengal photodynamic antimicrobial therapy (PDAT) using different irradiation energy levels and photosensitizer concentrations for the inhibition of fungal keratitis isolates. Seven different fungi (Aspergillus fumigatus, Candida albicans, Curvularia lunata, Fusarium keratoplasticum, Fusarium solani, Paecilomyces variotii, and Pseudallescheria boydii) were isolated from patients with confirmed infectious keratitis. Experiments were performed in triplicate with suspensions of each fungus exposed to different PDAT parameters including a control, green light exposure of 5.4 J/cm2, 2.7 J/cm2 (continuous and pulsed), and 1.8 J/cm2 and rose bengal concentrations of 0.1%, 0.05%, and 0.01%. Plates were photographed 72 h after experimentation, and analysis was performed to assess fungal growth inhibition. PDAT using 5.4 J/cm2 of irradiation and 0.1% rose bengal completely inhibited growth of five of the seven fungal species. Candida albicans and Fusarium keratoplasticum were the most susceptible organisms, with growth inhibited with the lowest fluence and minimum rose bengal concentration. Fusarium solani, Pseudallescheria boydii, and Paecilomyces variotii were inhibited by lower light exposures and photosensitizer concentrations. Aspergillus fumigatus and Curvularia lunata were not inhibited by any PDAT parameters tested. Continuous and pulsed irradiation using 2.7 J/cm2 produced similar results. Rose bengal PDAT successfully inhibits the in vitro growth of five fungi known to cause infectious keratitis. Differences in growth inhibition of the various fungi to multiple PDAT parameters suggest that susceptibilities to PDAT are unique among fungal species. These findings support modifying PDAT parameters based on the infectious etiology. [ABSTRACT FROM AUTHOR]

Introduction: Fungal keratitis (FK) poses a severe threat to vision, potentially leading to blindness if not promptly addressed. Clitoria ternatea flower extracts have a history of use in Ayurvedic and Indian traditional medicines, particularly for treating eye ailments. This study investigates the antifungal and antibiofilm effects of Clitoria ternatea flower extracts on the FK clinical isolate Coniochaeta hoffmannii. Structural details and key compound identification were analysed through FTIR and GC-MS. Methods: The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of Clitoria ternatea flower extracts were determined using broth dilution and well plate techniques. Biofilm inhibitory activity was assessed through microscopic evaluation, while anti-irritant and cytotoxic properties were evaluated using CAE-EI and MTT assays. Through GC-MS and FT-IR analysis the compounds dissolved in the extract and their functional group were studied, and their toxicity screening and pharmacokinetic prediction were conducted in silico. Subsequently, compounds with high corneal permeability were further identified, and molecular docking and simulation studies at 150 ns were used to investigate their interactions with fungal virulence factors and human inflammatory proteins. Results and Discussion: At a concentration of 250 μg/mL, the Clitoria ternatea flower extract displayed effective biofilm inhibition. MIC and MFC values were determined as 500 and 1000 μg/mL, respectively. CAE-EI and MTT assays indicated no significant irritant and cytotoxic effects up to a concentration of 3 mg/mL. Compounds like 9,9-dimethoxybicyclo[3.3.1]nonane-2,4-dione showed high corneal permeability with strong and stable interactions with fungal virulence cellobiose dehydrogenase, endo β 1,4 xylanase, and glucanase, as well as corneal inflammation-associated human TNF-a and Interleukin IL-1b protein targets. The findings indicate that extracts from C. ternatea flowers could be formulated for an effective and safe alternative for developing new topical FK therapeutics. [ABSTRACT FROM AUTHOR]

Objectives: The aim of the present study was to evaluate any conjunctival metaplastic changes by impression cytology in patients who underwent topical 1% voriconazole treatment for severe fungal keratitis. Materials and Methods: The study was conducted at Ege University Faculty of Medicine, Departments of Ophthalmology and Medical Pathology. Patients who were treated with 1% topical voriconazole for fungal keratitis for at least 3 months were included. The used topical voriconazole treatment was initiated as one drop every hour and was tapered according to clinical improvement in all patients. Treatment was continued 4 times a day for at least 3 months. Impression cytology samples were collected at least 3 months after cessation of topical voriconazole from the affected eyes and from the fellow eyes as a control group. Collected specimens were transferred to the pathology department for evaluation and grading (Nelson's grading system). Results: The mean age of the patients was 57.68±17.32 years (range, 22-87 years). The impression cytology grade of the inferior bulbar conjunctiva was 1.73±0.77 (range, 0-3) in the study group and 1.19±0.98 (range, 0-3) in the control group (p=0.03). The impression cytology grade of the temporal bulbar conjunctiva was 1.69±0.73 (range, 0-3) in the study group and 1.15±0.88 (range, 0-3) in the control group (p=0.02). The impression cytology grades of the nasal and superior bulbar conjunctiva did not differ statistically (p values 0.13 and 0.17, respectively). Conclusion: Topical voriconazole is an effective broad-spectrum antifungal drug, but it induces conjunctival squamous metaplasia. Clinicians should be aware of this possible side effect of topical voriconazole and should carefully evaluate the conjunctiva of treated patients at each visit to detect possible metaplastic changes. [ABSTRACT FROM AUTHOR]

Purpose: Corneal infections are a leading cause of visual impairment and blindness worldwide. Here we applied high-resolution transcriptomic profiling to assess the general and pathogen-specific molecular and cellular mechanisms during human corneal infection. Methods: Clinical diagnoses of herpes simplex virus (HSV) (n=5) and bacterial/ fungal (n=5) keratitis were confirmed by histology. Healthy corneas (n=7) and keratoconus (n=4) samples served as controls. Formalin-fixed, paraffinembedded (FFPE) human corneal specimens were analyzed using the 3' RNA sequencing method Massive Analysis of cDNA Ends (MACE RNA-seq). The cellular host response was investigated using comprehensive bioinformatic deconvolution (xCell and CYBERSORTx) analyses and by integration with published single cell RNA-seq data of the human cornea. Results: Our analysis identified 216 and 561 genes, that were specifically overexpressed in viral or bacterial/fungal keratitis, respectively, and allowed to distinguish the two etiologies. The virus-specific host response was driven by adaptive immunity and associated molecular signaling pathways, whereas the bacterial/fungal-specific host response mainly involved innate immunity signaling pathways and cell types. We identified several genes and pathways involved in the host response to infectious keratitis, including CXCL9, CXCR3, and MMP9 for viral, and S100A8/A9, MMP9, and the IL17 pathway for bacterial/ fungal keratitis. Conclusions: High-resolution molecular profiling provides new insights into the human corneal host response to viral and bacterial/fungal infection. Pathogenspecific molecular profiles may provide the foundation for novel diagnostic biomarker and therapeutic approaches that target inflammation-induced damage to corneal host cells with the goal to improve the outcome of infectious keratitis. [ABSTRACT FROM AUTHOR]

Introduction: This case report describes a rare case of fungal keratitis following femtoLASIK. Despite targetted antifungal therapy, this case necessitated an innovative surgical approach to manage an unexpected corneal perforation. Case Presentation: A 35-year-old male presented 3 weeks post-femtoLASIK for myopic astigmatism with discomfort and reduced vision in his right eye. He was diagnosed with fungal keratitis surgery caused by Purpureocillium lilacinum and was treated with a myriad of therapy. Unfortunately, the patient developed corneal perforation during flap lift and flap bed irrigation. An innovative approach involving a tectonic autograft using a viable LASIK flap, followed by prompt penetrating keratoplasty, was utilised. Conclusion: This technique was effective and able to mitigate the progression to an open globe. [ABSTRACT FROM AUTHOR]

Fungal keratitis is a major cause of corneal blindness worldwide. Compared to other types of infectious keratitis, fungal keratitis has a relatively poor prognosis because of various factors such as delayed patient presentation and diagnosis. Although associated in earlier studies with poverty and low socioeconomic status, military personnel stationed in tropical and subtropical climates, in low-resource settings, are at risk. Here, we report a case of a 20-year-old active duty contact lens–wearing military service member stationed at Guantanamo Bay who developed a severe vision-threatening fungal keratitis in her left eye. Enhancing health and safety precautions in at-risk settings, maintaining vigilance, and leveraging new imaging modalities will be important to ensure early recognition and treatment. [ABSTRACT FROM AUTHOR]

Purpose: Natamycin (NT) is used as a first-line antifungal prescription in the treatment of fungal keratitis (FK) and is commercially available as a 5% w/v ophthalmic suspension. NT shows poor water solubility and light sensitivity. Thus, the present investigation is aimed to enhance the fraction of NT in solution in the commercial formulation by adding cyclodextrins (CDs), thereby improving the delivery of the drug into deeper ocular tissues. Methods: The solubility of NT in different CDs, the impact of ultraviolet (UV) light exposure, stability at 4°C and 25°C, in vitro release, and ex vivo transcorneal permeation studies were performed. Results: NT exhibited the highest solubility (66-fold) in randomly methylated-β-cyclodextrin (RM-βCD) with hydroxypropyl-βCD (HP-βCD) showing the next highest solubility (54-fold) increase in comparison to market formulation Natacyn® as control. The stability of NT-CD solutions was monitored for 2 months (last-time point) at both storage conditions. The degradation profile of NT in NT-RM-βCD and NT-HP-βCD solutions under UV-light exposure followed first-order kinetics exhibiting half-lives of 1.2 h and 1.4 h, respectively, an almost 3-fold increase over the control solutions. In vitro release/diffusion studies revealed that suspensions containing RM-βCD and HP-βCD increased transmembrane flux significantly (3.1-fold) compared to the control group. The transcorneal permeability of NT from NT-RM-βCD suspension exhibited an 8.5-fold (P < 0.05) improvement compared to Natacyn eyedrops. Furthermore, the addition of RM-βCD to NT suspension increases the solubilized fraction of NT and enhances transcorneal permeability. Conclusion: Therefore, NT-RM-βCD formulations could potentially lead to a decreased frequency of administration and significantly improved therapeutic outcomes in FK treatment. [ABSTRACT FROM AUTHOR]

Fungal keratitis is a relatively rare yet severe ocular infection that can lead to profound vision impairment and even permanent vision loss. Rapid and accurate diagnosis plays a crucial role in the effective management of the disease. A patient's history establishes the initial clinical suspicion since it can provide valuable clues to potential predisposing factors and sources of fungal exposure. Regarding the evaluation of the observed symptoms, they are not exclusive to fungal keratitis, but their timeline can aid in distinguishing fungal keratitis from other conditions. Thorough clinical examination of the affected eye with a slit-lamp microscope guides diagnosis because some clinical features are valuable predictors of fungal keratitis. Definitive diagnosis is established through appropriate microbiological investigations. Direct microscopic examination of corneal scrapings or biopsy specimens can assist in the presumptive diagnosis of fungal keratitis, but culture remains the gold standard for diagnosing fungal keratitis. Advanced molecular techniques such as PCR and MALDI-ToF MS are explored for their rapid and sensitive diagnostic capabilities. Non-invasive techniques like in vivo confocal microscopy (IVCM) and optical coherence tomography (OCT) are useful for real-time imaging. Every diagnostic technique has both advantages and drawbacks. Also, the selection of a diagnostic approach can depend on various factors, including the specific clinical context, the availability of resources, and the proficiency of healthcare personnel. [ABSTRACT FROM AUTHOR]

Purpose: To analyze the influence of infiltrate size, depth, and organism on the outcome of microbial keratitis. Design: Retrospective comparative study. Methods: Medical records of patients with infective keratitis, who reported from January 2015 to December 2019 to a tertiary eye care center, were analyzed. Size and depth of ulcer at presentation were the factors used to group patients, and the influence on the outcome of the organism causing it was analyzed. Grouping was as follows: group A: ulcer size <6 mm/anterior to midstromal infiltrate, group B: ulcer < 6 mm/full-thickness infiltrate, group C: ulcer >6 mm/anterior to midstromal infiltrate, group D: ulcer > 6 mm/full-thickness infiltrate. Patients with viral keratitis or unidentified organism were excluded. Response to treatment and best-corrected visual acuity (BCVA) at the final follow-up were the outcome measures. Results: In the study, 1117/6276 patients were included, with 60.8% patients in group A. A significant improvement in visual acuity was noted in groups A/B compared to groups C/D. Group A had the best response to medical management, irrespective of the organism. Higher risk for surgery was noted in group C compared to group B, with group A as the reference. Overall resolution with medical treatment was noted in 70% miscellaneous keratitis, 64.8% bacterial keratitis, 64.3% mixed keratitis, 62.5% acanthamoeba keratitis, 52.6% fungal keratitis, and 12.1% Pythium keratitis. Bacteria and acanthamoeba responded better to medical management than fungal keratitis, whereas Pythium had the highest risk for surgery. Conclusion: An interplay between virulence of the organism along with depth and size of the infiltrate determines the outcome of microbial keratitis. [ABSTRACT FROM AUTHOR]

The purpose of this work was to investigate the feasibility of a novel ophthalmic formulation of amphotericin B-encapsulated silk fibroin nanoparticles incorporated in situ hydrogel (AmB-FNPs ISG) for fungal keratitis (FK) treatment. AmB-FNPs ISG composites were successfully developed and have shown optimized physicochemical properties for ocular drug delivery. Antifungal effects against Candida albicans and in vitro ocular irritation using corneal epithelial cells were performed to evaluate the efficacy and safety of the composite formulations. The combined system of AmB-FNPs-ISG exhibited effective antifungal activity and showed significantly less toxicity to HCE cells than commercial AmB. In vitro and ex vivo mucoadhesive tests demonstrated that the combination of silk fibroin nanoparticles with in situ hydrogels could enhance the adhesion ability of the particles on the ocular surface for more than 6 h, which would increase the ocular retention time of AmB and reduce the frequency of administration during the treatment. In addition, AmB-FNP-PEG ISG showed good physical and chemical stability under storage condition for 90 days. These findings indicate that AmB-FNP-PEG ISG has a great potential and be used in mucoadhesive AmB eye drops for FK treatment. [ABSTRACT FROM AUTHOR]

Background: In this study we wanted to assess the prevalence of specific fungal pathogens, analyze the influence of demographic factors on the spectrum of fungal species responsible for fungal corneal ulcers and also determine the effectiveness of treatment. Methods: This was a prospective study carried out over a period of two years involving 53 corneal ulcer patients. Corneal scraping materials collected from the patients were sent for a 10% KOH/NaOH stain and Sabouraud dextrose agar for culture and sensitivity by micro-broth dilution technique. All the patients who were KOH stain positive and/or culture positive in Sabouraud medium were considered for the study. The patients were emperically treated with Topical Natamycin 5percent eye drop. As per culture and sensitivity report, voriconazole (1%), topical amphotericin-B or a systemic anti-fungal drug like Itraconazole (200 mg) was added. All patients were followed up daily for one week, every one week up to one month, and every two weeks up to three months till the epithelium healed, as evidenced by the negative FL stain and disappearance of signs and symptoms. The collected data was tabulated and analyzed using SPSS (Statistical Package for Social Science) version 22.0. For statistical analysis, mean, frequency, percentage and Pearson's chi-square test were performed; a p-value <0.05 was considered to be statistically significant. Results: The maximum number of cases were seen in males in the range of 51-60 years and in females aged 41-50 years, who were mostly involved in outdoor work. Males were more affected (62.26%) than females (37.73%). 52.83% were agricultural workers or farmers, with vegetative matters (39.60%) being the most common traumatic agent. 26.4% of study subjects were diabetics and 13% had a history of using topical steroids. A central location for corneal ulcers was present in 50.9% of cases, and a paracentral location was present in 39.6% of cases. In 77.4% of patients, the ulcer was ≤6 mm. 35 (66%) out of 53 study subjects fell within the range of 34%-67% depth of corneal involvement. 50.94% of study subjects had visual acuity between <6/60 and >1/60. All study subjects had a 10% KOH smear positive. 31 study subjects had a positive SDA culture, the rest had negative and variable reports. Aspergillus was the predominant organism in 45 (84.9%), followed by fusarium in 8 (15.1%). All fungal ulcers were sensitive to natamycin (100%) with a variable sensitivity to voriconazole 17 (32.1%), amphotericin B 7 (13.2%) and itraconazole 15 (28.3%). Conclusion: The present study has brought to light again the fact that fungal keratitis continues to be a major concern for loss of sight, especially in the rural, agricultural population. Goals directed towards proper education, early recognition and appropriate treatment will go a long way towards mitigating the problem of this potentially sight-threatening condition. [ABSTRACT FROM AUTHOR]

Fungal keratitis is a major ophthalmic problem worldwide specially in tropical and subtropical region. It is common in India due to the tropical climate and a large agrarian population that is at risk. Materials & Methods: The 3 cases for this case series we have taken from ophthalmology OPD having suspected fungal ulcer or vegetative trauma to the eye. Conjunctival swab cultures were carried out from affected eye and do the mycological investigations (10% KOH & culture over the SDA culture media) and clinically normal cases to study the fungal flora of conjunctival sac. Results: The fungal etiology in the causation of corneal ulcer varies in relation to age, sex and occupation of the patients and climatic condition of the region. The prevalence of mycotic corneal ulcer is more among male agriculture workers in the age group of 40 -60 years. Fungal corneal ulcer occurs more frequently during the harvesting season of the year. Minor vegetative trauma to cornea acts as precipitating factor of kerato mycosis mostly by the vegetative origin like paddy leaves straw, etc. Out of topical antifungal agents Fluconazole, Natamycin and voriconazole, Fluconazole has edge over Natamycin and Voriconazole in treating mycotic corneal ulcer. [ABSTRACT FROM AUTHOR]

A 68-year-old diabetic male with Fuchs endothelial corneal dystrophy cataract underwent combined DMEK and cataract surgery of the left eye. Post-operative course was complicated by a partial graft detachment on POD 3, treated with a re-bubbling procedure. The patient subsequently developed a corneal infiltrate, cultured by aqueous sample, that was found to be C. parapsilosis. Oral fluconazole and voriconazole, topical voriconazole 1%, and amphotericin B as well as intracameral and intrastromal voriconazole and amphotericin B were employed. By post-operative day 45, symptoms and signs of DMEK stromal C. parapsilosis keratitis had resolved, and a corneal scar remained. Best corrected visual acuity, at post-operative month 4, was 20/25-2 without correction. Post-DMEK fungal stromal keratitis is a rare post-operative complication. We present a case of C. parapsilosis DMEK stromal keratitis and describe diagnostic and therapeutic modalities that allowed for resolution of the infection, without explantation of the patient's graft, and preservation of visual acuity. [ABSTRACT FROM AUTHOR]

Fungal keratitis represents a potentially sight-threatening infection associated with poor prognosis, as well as financial burden. Novel diagnostic methods include polymerase-chain-reaction (PCR)-based approaches, metagenomic deep sequences, in vivo confocal microscopy, and antifungal susceptibility testing. The ideal therapeutic approaches and outcomes have been widely discussed in recent times, with early therapy being of the utmost importance for the preservation of visual acuity, minimizing corneal damage and reducing the scar size. However, combination therapy can be more efficacious compared to monotherapy. Understanding the pathogenesis, early diagnosis, and prevention strategies can be of great importance. In this narrative, we discuss the recent progress that may aid our understanding of the diagnosis, treatment, and prevention of mycotic keratitis. [ABSTRACT FROM AUTHOR]

We present two cases with a history of trauma to the cornea and after a few days patients developed symptoms of corneal ulcers with one showing hypopyon as well. Due to strong suspicion of fungal keratitis both cases were treated with topical and intravenously voriconazole. Fungal culture showed white fluffy growth which was identified as Schizophyllum commune by conventional and molecular methods. In both cases surgical intervention was essential. Therapeutic keratoplasty was done in both cases but failed. Unfortunately, both patients lost vision in the affected eyes.

PurposeDevelop computer vision models for image-based differentiation of bacterial and fungal corneal ulcers and compare their performance against human experts.DesignCross-sectional comparison of diagnostic performance.ParticipantsPatients with acute, culture-proven bacterial or fungal keratitis from 4 centers in South India.MethodsFive convolutional neural networks (CNNs) were trained using images from handheld cameras collected from patients with culture-proven corneal ulcers in South India recruited as part of clinical trials conducted between 2006 and 2015. Their performance was evaluated on 2 hold-out test sets (1 single center and 1 multicenter) from South India. Twelve local expert cornea specialists performed remote interpretation of the images in the multicenter test set to enable direct comparison against CNN performance.Main outcome measuresArea under the receiver operating characteristic curve (AUC) individually and for each group collectively (i.e., CNN ensemble and human ensemble).ResultsThe best-performing CNN architecture was MobileNet, which attained an AUC of 0.86 on the single-center test set (other CNNs range, 0.68-0.84) and 0.83 on the multicenter test set (other CNNs range, 0.75-0.83). Expert human AUCs on the multicenter test set ranged from 0.42 to 0.79. The CNN ensemble achieved a statistically significantly higher AUC (0.84) than the human ensemble (0.76; P < 0.01). CNNs showed relatively higher accuracy for fungal (81%) versus bacterial (75%) ulcers, whereas humans showed relatively higher accuracy for bacterial (88%) versus fungal (56%) ulcers. An ensemble of the best-performing CNN and best-performing human achieved the highest AUC of 0.87, although this was not statistically significantly higher than the best CNN (0.83; P = 0.17) or best human (0.79; P = 0.09).ConclusionsComputer vision models achieved superhuman performance in identifying the underlying infectious cause of corneal ulcers compared with cornea specialists. The best-performing model, MobileNet, attained an AUC of 0.83 to 0.86 without any additional clinical or historical information. These findings suggest the potential for future implementation of these models to enable earlier directed antimicrobial therapy in the management of infectious keratitis, which may improve visual outcomes. Additional studies are ongoing to incorporate clinical history and expert opinion into predictive models.

The problem of diagnosis and treatment of fungal keratitis (FK) is very acute. Due to the slow development of clinical features and the absence of clear pathognomonic signs, this disease is characterized by a late start of the introduction of adequate etiotropic therapy. Often this leads to the development of large corneal defects requiring surgical intervention. Diagnostic methods are divided into invasive and non-invasive. Invasive methods include the study of scrapings from the surface of the cornea from the site of ulceration, biopsy of the corneal stroma or moisture of the anterior chamber using microscopic, cultural methods or polymerase chain reaction (PCR). Non-invasive techniques include confocal microscopy and optical coherence tomography of the anterior segment. They allow you to dynamically monitor the course of the pathological process and the response to ongoing therapy. Promising methods are also the detection of (1,3)-β-D-glucans in tears, the detection of the pathogen using MALDI-TOF MS. The gold standard for the treatment of FK in the world is the topical application of 5 % Natamycin (approved by the FDA, but not available in Russia). Fluconazole, Voriconazole and Amphotericin B, available in Russia, are also widely used, but their topical use is possible only in off label format. In the presence of hypopyon or an increase in the size and depth of the infiltrate, despite ongoing treatment, immediate surgical treatment is required in order to preserve the integrity of the eyeball. Such treatments include penetrating keratoplasty, anterior lamellar keratoplasty, amniotic membrane transplantation, conjunctival flaps, corneal collagen cross-linking (with unproven efficacy), and argon laser. A promising method for the treatment of FK can be the use of Ag(10 %):InP/ZnS MPA quantum dots as monotherapy or as a bioconjugate with known antifungal drugs.

Fungal keratitis (FK) is 8–30 % in the structure of infectious inflammation of the cornea. There are 2 main types of mushroom growth — mycelial and yeast. Mycelial (mold) fungi grow in the form of special branched microscopic tubes — hyphae. Yeast fungi form compact colonies of individual oval cells. Due to the peculiarities of the yeast structure, the tendency to rapid spread in the tissues is reduced, which determines the less aggressive clinical course of such keratomycosis compared to mold. Until the 50s of the 20th century, the occurrence of FK in the world was low. However, probably with the introduction of corticosteroid and antibacterial drugs into medicine, their prevalence began to grow. The highest frequency of occurrence of FK is in regions with a hot climate and high involvement of the population in agriculture. The main provoking factor for the appearance of FK is corneal injury with damage to the epithelium and adhesion to the Bowman’s membrane or stroma components. Highly adhesive fungi (Aspergillus spp., Candida spp.) trigger a cascade of immune inflammatory reactions, production of reactive oxygen species and matrix metalloproteases-9, which leads to the destruction of lamellae. Fungi with low adhesive ability (Fusarium spp.) can grow parallel to lamellae for a long time and indefinitely without inducing pronounced inflammation. Symptoms of FC are similar to those observed in other forms of infectious keratitis, but more often they develop more slowly (5–10 days) and are less acute. A defect against the background of mycelial FC is more often characterized by jagged edges, a raised slough, and a non-yellow color. Yeast FK is manifested by oval ulceration of the epithelium with expanding, more sharply demarcated, densely focal suppuration.

AIM: To analyze a series of antimicrobial peptides (AMPs) in corneal tissue from individuals with fungal keratitis (FK) during the active phase of the fungus infection and after healing. METHODS: Patients undergone lamellar keratoplasty for the treatment of severe FK or corneal scar had their corneal buttons sampled. Quantitative real-time polymerase chain reaction (PCR) was used to ascertain the gene expression of human beta-defensin (HBD)-1, -2, -3, -9, S100A7, 8, 9, and LL-37. RESULTS: All AMPs' messenger ribonucleic acid (mRNA) expression was considerably elevated in all samples (n=12). In contrast to controls, where HBD-2, -3, and S100A7 mRNAs were expressed at very low levels, it was discovered that HBD-1, -9, S100A8, S100A9, and LL-37 were constitutively expressed in all healed samples (n=4). HBD-1, -2 -3, S100A7, and LL-37 mRNAs were significantly increased in all active FK samples (n=8). The levels of HBD-9, S100A8, and S100A9 mRNAs were moderately upregulated in all active FK samples. Subgroup comparison showed that HBD-2 was significantly increased in Fusarium keratitis samples (n=5), and LL-37 mRNAs were significantly enhanced in Aspergillus keratitis samples (n=3). Whereas there was not significantly increased of HBD-1, -3, -9, S100A7, 8, 9 mRNA in Aspergillus keratitis samples compared with Fusarium keratitis samples. CONCLUSION: AMPs expression is increased in active FK, but not all AMPs are equally expressed. HBD-2 and LL-37 expression levels are the highest, showing some specificity of AMP expression related to FK. Human AMPs, particularly HBD-2 may play a significant role in Fusarium keratitis and LL-37 might be the key player in Aspergillus keratitis.

This study quantifies the performance of an international cohort of cornea specialists in image-based differentiation of bacterial and fungal keratitis, identifying significant regional variation and establishing a reference standard for comparison against machine learning models.

The article discusses the increasing number of corneal grafts performed in Australia and the potential complications that can arise, particularly infectious keratitis. The incidence of infectious keratitis varies by geographic region and can result in corneal scarring, reduced vision, graft failure, or loss of the eye. The article presents findings from a longitudinal cohort study on corneal transplants, highlighting the cumulative incidence of infectious keratitis and the types of infective organisms involved. The study also examines antibiotic resistance patterns and discusses the importance of preventing infectious keratitis through proactive management and patient education. The article concludes by noting the potential benefits of lamellar keratoplasty in reducing the risk of infectious keratitis and emphasizes the need for long-term monitoring and ocular surface management to ensure graft success. [Extracted from the article]

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.

Background: Fungal keratitis is an important cause of ocular morbidity in developing countries. Aims and Objectives: To study fungal keratitis in detail along with its outcome. Materials and Methods: This is a retrospective study of fungal keratitis that had presented between October 2013 and March 2015. Results: 168 fungal ulcers were enrolled. 145 had fungus isolated in the culture; 23 had fungal elements seen only in potassium hydroxide mount examination. The average age of patients was 46.7 years. 55.3% were male. 75% were farmers. Patients presented at an average of 23.6 days since the onset of symptoms. In 85 cases (50.6%), trauma was the risk factor followed by steroid use (12.5%, n=21) and diabetes mellitus (7.7%, n=13). 72 out of 85 cases of trauma were due to vegetative matter. 94 (55.9%) ulcers had hypopyon. 56 (33.3%) ulcers had infiltrate size of ≥¼ of corneal surface. 12 (7.1%) ulcers were perforated at presentation. Out of 145 fungal isolates, Aspergillus species and Fusarium species were isolated in equal numbers (n=41, 28.3% each), followed by unidentified hyaline fungus (14.4%, n=21). The ulcers were treated with combination of topical natamycin 5% and fluconazole 0.3% with or without oral fluconazole. 111 (66.1%) fungal ulcers improved with medical treatment, 37 (n=22.0%) underwent therapeutic penetrating keratoplasty, 6 (3.6%) were eviscerated and outcome unknown in 14 (8.3%). Smaller-sized ulcers, ulcers without hypopyon and those presenting within 7 days had better prognosis (>80% healing with medical treatment) with statistical significance. Conclusion: Farmers were constantly at risk of fungal keratitis due to work-related trauma. Fungal ulcers presented late with large sized ulcers and with complications, thus making treatment challenging and necessitating surgical intervention. Timely treatment had better prognosis.

Background: Corneal blindness is a major public health problem worldwide and preventable cause of blindness in India. Corneal blindness is the second most common cause of blindness, after cataract, in developing countries. Aims and Objectives: A clinical study of keratomycosis to compare the efficacy of topical 10% NaCl with 5% natamycin (Group A) versus topical 5% natamycin (Group B) alone as a treatment strategy. Materials and Methods: This prospective, randomized, interventional, and comparative study with parallel design enrolled 100 cases diagnosed with unilateral keratomycosis and fulfilling the inclusion criteria, who presented to the outpatient department of Ophthalmology, Maharani Laxmi Bai Medical College and Hospital, Jhansi, Uttar Pradesh, between April 2021 and June 2022 (15 months). Results: Maximum patients in both the study groups belonged to the age group of 41–50 years showed male preponderance and belonged to the low socioeconomic status. Maximum patients in both the study groups had shown total regression in 66 cases with 41 cases from Group A and 25 cases from Group B, respectively. Regression was not seen in 34 cases with 9 cases belonging to Group A and 25 cases belonging to Group B. Maximum patients in study Group A had shown ulcer regression in 3.56 average weeks duration, while it was in 4.50 average weeks duration in Group B. Conclusion: This comparative and interventional study demonstrates that the study Group A receiving 10% sodium chloride solution with 5% natamycin helps in faster healing of corneal ulcer, rate of progression of ulcer is slowed down, and complications are less in comparison to Group B receiving 5% Natamycin alone owning to the anti-edema property of hypertonic saline. Hence, topical 10% NaCl solution can be used with 5% natamycin, as a cost-effective adjunct in the management of fungal keratitis.

AIM: To investigate whether the two-step strategy [conjunctival flap covering surgery (CFCS) combined with secondary deep anterior lamellar keratoplasty (DALK)] is effective for patients with high-risk fungal keratitis (FK). METHODS: In this noncomparative, retrospective case series, 10 subjects (6 males, 4 females) with a mean age of 56.5±7.1 (range 47-72)y with high-risk FK undergone the two-step strategy were included. Reported outcome measures were healing of the corneal ulcer, recurrence of FK, reject reaction, improvement in best corrected visual acuity (BCVA) and relevant complications. RESULTS: The average diameter of corneal infiltrates was 7.50±0.39 mm, ranging from 6.94 to 8.13 mm. The mean depth of corneal infiltrates was 422.4±77.1 μm, ranging from 350 to 535 μm. The mean corneal thickness was 597.4±117.3 μm, ranging from 458 to 851 μm. Hypopyon and endothelial plaques were presented in all patients. The period between the two steps was 3.65±0.9 (ranging from 3 to 5)mo. The graft diameter was 7.75±0.39 mm. At the last follow-up (average 9.25±3.39, ranging from 5.5 to 17mo), no fungal recurrence or graft rejection appeared, and all patients showed improvement of BCVA. One patient suffered from liver function impairment due to oral voriconazole for 4wk and recovered spontaneously after 1wk of drug withdrawal. CONCLUSION: The two-step strategy is safe and effective in the treatment of high-risk FK by transforming intentional therapeutic penetrating keratoplasty during acute infection to later optical DALK. It is a practical strategy, especially in areas lacking fresh donor corneas and eye bank services.

IntroductionFungal keratitis (FK) poses a severe threat to vision, potentially leading to blindness if not promptly addressed. Clitoria ternatea flower extracts have a history of use in Ayurvedic and Indian traditional medicines, particularly for treating eye ailments. This study investigates the antifungal and antibiofilm effects of Clitoria ternatea flower extracts on the FK clinical isolate Coniochaeta hoffmannii. Structural details and key compound identification were analysed through FTIR and GC-MS.MethodsThe minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of Clitoria ternatea flower extracts were determined using broth dilution and well plate techniques. Biofilm inhibitory activity was assessed through microscopic evaluation, while anti-irritant and cytotoxic properties were evaluated using CAE-EI and MTT assays. Through GC-MS and FT-IR analysis the compounds dissolved in the extract and their functional group were studied, and their toxicity screening and pharmacokinetic prediction were conducted in silico. Subsequently, compounds with high corneal permeability were further identified, and molecular docking and simulation studies at 150 ns were used to investigate their interactions with fungal virulence factors and human inflammatory proteins.Results and DiscussionAt a concentration of 250 µg/mL, the Clitoria ternatea flower extract displayed effective biofilm inhibition. MIC and MFC values were determined as 500 and 1000 µg/mL, respectively. CAE-EI and MTT assays indicated no significant irritant and cytotoxic effects up to a concentration of 3 mg/mL. Compounds like 9,9-dimethoxybicyclo[3.3.1]nonane-2,4-dione showed high corneal permeability with strong and stable interactions with fungal virulence cellobiose dehydrogenase, endo β 1,4 xylanase, and glucanase, as well as corneal inflammation-associated human TNF-α and Interleukin IL-1b protein targets. The findings indicate that extracts from C. ternatea flowers could be formulated for an effective and safe alternative for developing new topical FK therapeutics.

ObjectiveThe purpose of this study is to evaluate the efficacy and safety of the local application of silver nitrate (LASN) as an adjuvant treatment before deep lamellar keratoplasty (DLKP) for fungal keratitis responding poorly to medical treatment.MethodsA total of 12 patients (12 eyes) with fungal keratitis responding poorly to medical treatment (for at least 2 weeks) were included. LASN was performed using 2% silver nitrate, the ulcer was cleaned and debrided, and then, the silver nitrate cotton stick was applied to the surface of the ulcer for a few seconds. The effect of LASN was recorded. The number of hyphae before and after treatment was determined by confocal microscope. After the condition of the ulcer improved, DLKP was performed. Fungal recurrence, best-corrected visual acuity (BCVA), loose sutures, and endothelial cell density (ECD) were recorded in detail.ResultsClinical resolution of corneal infiltration and edema was observed, and the ulcer boundary became clear in all 12 patients after 7–9 days of LASN. Confocal microscopy showed that the number of hyphae was significantly reduced. Ocular pain peaked on days 1 and 2 after treatment, and 9 patients (75%, day 1) and 1 patient (8.3%, day 2) required oral pain medication. During the follow-up period after DLKP, no fungal recurrence and loose sutures were observed. After the operation, the BCVA of all patients improved. The mean corneal ECD was 2,166.83 ± 119.75 cells/mm2.ConclusionThe LASN was safe and effective and can be well tolerated by patients. Eye pain can be relieved quickly. LASN as an adjuvant treatment before DLKP might be a promising therapeutic strategy.

Background: Beauveria bassiana is a filamentous fungus commonly used as an insecticide that rarely causes keratitis. Methods: Patients affected by Beauveria bassiana keratitis were retrospectively recruited at San Raffaele Hospital (Milan, Italy) between 2020 and 2022. All subjects underwent comprehensive ophthalmic evaluation, including in vivo confocal microscopy (IVCM) and microbiologic examination of corneal scrapings. Beauveria bassiana was identified using 18S rDNA targeted PCR. Results: Four eyes of four patients (51 ± 8.8 years old) were evaluated. The main risk factors were soft contact lens wear (75%) and trauma with vegetative matter (50%). A superficial infiltrate was displayed in the majority of patients. Three cases (75%) showed hyphae on IVCM. All patients showed clinical improvement after topical antifungal therapy, although mostly through a combination of two antifungals (75%). One patient with a deeper infection required a systemic antifungal agent after one month of topical therapy. All cases required debridement to reduce the microbial load and enhance drug penetration. All patients experienced keratitis resolution following medical treatment (average: 3.3 months). Conclusions: The identification of risk factors and the early diagnosis of Beauveria bassiana keratitis are fundamental in order to avoid its penetration in the deeper corneal stromal layers. Topical antifungal drugs, possibly accompanied by ulcer debridement, may be a successful treatment if instilled from the early phases of the disease. [ABSTRACT FROM AUTHOR]

Infectious keratitis (IK) is a major cause of corneal opacity. IK can be caused by a variety of microorganisms. Typically, fungal ulcers carry the worst prognosis. Fungal cases can be subdivided into filamentous and yeasts, which shows fundamental differences. Delays in diagnosis or initiation of treatment increase the risk of ocular complications. Currently, the diagnosis of IK is mainly based on slit-lamp examination and corneal scrapings. Notably, these diagnostic methods have their drawbacks, including experience-dependency, tissue damage, and time consumption. Artificial intelligence (AI) is designed to mimic and enhance human decision-making. An increasing number of studies have utilized AI in the diagnosis of IK. In this paper, we propose to use AI to diagnose IK (model 1), differentiate between bacterial keratitis and fungal keratitis (model 2), and discriminate the filamentous type from the yeast type of fungal cases (model 3). Overall, 9329 slit-lamp photographs gathered from 977 patients were enrolled in the study. The models exhibited remarkable accuracy, with model 1 achieving 99.3%, model 2 at 84%, and model 3 reaching 77.5%. In conclusion, our study offers valuable support in the early identification of potential fungal and bacterial keratitis cases and helps enable timely management. [ABSTRACT FROM AUTHOR]

Corneal disorders and diseases are prevalent in the field of clinical ophthalmology. Fungal keratitis, one of the major factors leading to visual impairment and blindness worldwide, presents significant challenges for traditional topical eye drop treatments. The objective of this study was to create biocompatible 3D-crosslinked hydrogels for drug delivery to the cornea, intending to enhance the bioavailability of ophthalmic drugs. Firstly, a series of flexible and porous hydrogels were synthesized (free-radical polymerization), characterized, and evaluated. The materials were prepared by the free-radical polymerization reaction of 1-vinyl-2-pyrrolidinone (also known as N-vinylpyrrolidone or NVP) and 1,6-hexanediol dimethacrylate (crosslinker) in the presence of polyethylene glycol 1000 (PEG-1000) as the porogen. After the physicochemical characterization of these materials, the chosen hydrogel demonstrated outstanding cytocompatibility in vitro. Subsequently, the selected porous hydrogels could be loaded with voriconazole, an antifungal medication. The procedure was adapted to realize a loading of 175 mg voriconazole per ring, which slightly exceeds the amount of voriconazole that is instilled into the eye via drop therapy (a single eye drop corresponds with approximately 100 mg voriconazole). The voriconazole-loaded rings exhibited a stable zero-order release pattern over the first two hours, which points to a significantly improved bioavailability of the drug. Ex vivo experiments using the established porcine eye model provided confirmation of a 10-fold increase in drug penetration into the cornea (after 2 h of application of the hydrogel ring, 35.8 ± 3.2% of the original dose is retrieved from the cornea, which compares with 3.9 ± 1% of the original dose in the case of eye drop therapy). These innovative hydrogel rods and rings show great potential for improving the bioavailability of ophthalmic drugs, which could potentially lead to reduced hospitalization durations and treatment expenses. [ABSTRACT FROM AUTHOR]

Aim: To determine the effectiveness and safety of photoactivated chromophore-corneal cross-linking (PACK-CXL) adjuvant in infectious keratitis by April 5, 2022. Methods: We searched randomized controlled trials (RCTs) comparing standard antibiotic treatment (SAT) plus PACK-CXL to SAT in infectious keratitis in Embase, MEDLINE with PubMed, Web of Science, and Cochrane Library. We independently screened and extracted data using predesigned tables. Cochrane's risk-of-bias tool was utilized to examine the quality of RCTs. A random-effects model was employed to determine the overall effect size of the meta-analyses. Grading of Recommendations, and Assessment, Development and Evaluations (GRADE) was also performed to examine the quality of evidence. Results: Seven eligible RCTs with 283 patients were acquired. Adjuvant PACK-CXL reduced the time needed to perform corneal healing in fungal keratitis (− 1.33 months; 95% CI, − 1.83 to − 0.42, I2 = 0%, P < 0.05) as compared to SAT alone. The risks of adverse events were not significantly different both in fungal and bacterial keratitis. Due to the substantial heterogeneity among studies, such as population, the type and severity of infectious keratitis, drug regimens of SAT, PACK-CXL protocol, and the judgment of subjective outcomes, the evidence grade was low. Conclusion: Adjuvant PACK-CXL accelerates fungal keratitis healing as compared to SAT alone. But more rigorous RCTs are required to determine the clinical effectiveness and safety. [ABSTRACT FROM AUTHOR]

Purpose: To determine the demographic and microbiological profile involved in the causation of corneal ulcers in Eastern India during the COVID era. Method: Patients presenting with corneal ulcers fulfilling the inclusion and exclusion criteria were taken as the case. The study duration was from January 2021 to December 2021. Socio-demographic details and information about risk factors were noted. A detailed corneal examination followed by corneal scraping was performed for microbiological evaluation. Results: In 1 year, 99 infective corneal ulcer patients were evaluated. Farmers (24.2%) were found to be maximally affected by corneal ulcers. The peak in cases was recorded from October to December (38.4%). Ocular trauma was the commonest risk factor (42.4%). The majority (80.8%) of patients were already on some topical antimicrobials. 22.2% of samples showed fungal filaments on KOH mount; 54.5% of these cases turned out to be culture-positive. 17.56% of KOH-negative samples turned out to be culture-positive (fungal). Overall, the culture positivity rate was 28.28% out of which fungal isolates were 89.28% and bacterial isolates were 10.72%. Fusarium species were identified as the most common organism contributing 42.85%, followed by Aspergillus fumigatus (14.28%). 10.72% of cases were culture positive for Pseudomonas aeuroginosa. Conclusion: Trauma with the organic matter was the predominant cause of fungal keratitis. In this study, fungal keratitis was found to be more common. Fusarium was the most common isolate. [ABSTRACT FROM AUTHOR]

The Aspergillus fumigatus unfolded protein response (UPR) is a two-component relay consisting of the ER-bound IreA protein, which splices and activates the mRNA of the transcription factor HacA. Spliced hacA accumulates under conditions of acute ER stress in vitro, and UPR null mutants are hypovirulent in a murine model of invasive pulmonary infection. In this report, we demonstrate that a hacA deletion mutant (ΔhacA) is furthermore avirulent in a model of fungal keratitis, a corneal infection, and an important cause of ocular morbidity and unilateral blindness worldwide. Interestingly, we demonstrate that A. fumigatus hacA is spliced in infected lung samples, but not in the cornea, suggesting the amount of ER stress experienced by the fungus varies upon the host niche. To better understand how the UPR contributes to fungal cell biology across a spectrum of ER-stress levels, we employed transcriptomics on the wild-type and ΔhacA strains in glucose minimal media (low stress), glucose minimal media with dithiothreitol (high stress), and gelatin minimal media as a proxy for the nutrient stress encountered in the cornea (mid-level stress). These data altogether reveal a unique HacA-dependent transcription under each condition, suggesting that HacA activity is finely-tuned and required for proper fungal adaptation in each environment. Taken together, our results indicate that the fungal UPR could serve as an important antifungal target in the setting of both invasive pulmonary and corneal infections. Author summary: Fungal keratitis has emerged as a leading cause of ocular morbidity and unilateral blindness worldwide. Relative to other infectious contexts, however, little is known about the fungal genes or pathways that regulate invasive growth and virulence in the corneal environment. In this report, we demonstrate that genetic disruption of the Aspergillus fumigatus unfolded protein response (UPR) abolishes the ability of the mold to establish infection in a mouse model of FK. Despite this critical role for virulence, however, we did not detect a concerted activation of the pathway beyond levels observed on standard medium, suggesting that the host environment is not an acute source of endoplasmic reticulum stress. Transcriptomic profiling of the wild-type and UPR-deficient strains under host-relevant nutrient conditions revealed a critical role for the pathway in regulating primary and secondary metabolism, cell wall biology, and mitochondrial function, all of which likely modulate fungal growth within and interactions with the host. These results expand our understanding of UPR regulation and function in this important mold pathogen and suggest the pathway could serve as a target for novel antifungals that improve visual outcomes in the setting of fungal keratitis. [ABSTRACT FROM AUTHOR]

Fungal keratitis (FK) is an invasive infection of the cornea primarily associated with Aspergillus and Fusarium species. FK is treated empirically with a limited selection of topical antifungals with varying levels of success. Though clinical infections are typically characterized by a dense network of mature mycelium, traditional models used to test antifungal susceptibility of FK isolates exclusively evaluate susceptibility in fungal cultures derived from asexual spores known as conidia. The purpose of this study was to characterize differences in fungal response when topical antifungal treatment is initiated at progressive phases of fungal development. We compared the efficacy of voriconazole and luliconazole against in vitro cultures of A. flavus and F. keratoplasticum at 0, 24, and 48 h of fungal development. A porcine cadaver corneal model was used to compare antifungal efficacy of voriconazole and luliconazole in ex vivo tissue cultures of A. flavus and F. keratoplasticum at 0, 24, and 48 h of fungal development. Our results demonstrate phase-dependent susceptibility of both A. flavus and F. keratoplasticum to both azoles in vitro as well as ex vivo. We conclude that traditional antifungal susceptibility testing with conidial suspensions does not correlate with fungal susceptibility in cultures of a more advanced developmental phase. A revised method of antifungal susceptibility testing that evaluates hyphal susceptibility may better predict fungal response in the clinical setting where treatment is often delayed until days after the initial insult. [ABSTRACT FROM AUTHOR]

To evaluate the efficacy and safety of hypochlorous acid (HOCI) eye drops in the treatment of fungal keratitis. A total of 96 patients (96 eyes) with fungal keratitis were randomly divided into two groups: group Ι (conventional treatment + topical HOCI eye drops); The group II (conventional treatment). According to its severity, those patients were divided into grade Ι or grade II. Use of fungal scraping and culture to identify the type of fungal infection, slit lamp examination, and corneal fluorescein staining to observe regression, and confocal corneal microscopy to assess fungal mycelial changes. The main outcome measures were the success rate, healing time, visual recovery, and complications. The Kaplan–Meier curve method was used to analysis of the survival function of days to cure between the two groups. There were no statistical differences between the two groups in terms of general condition, medical history, and grading. Corneal scraping results showed that all patients had filamentous fungi. For grade Ι patients, all patients were cured, and the patients in Group I showed faster healing speed than that in Group II (t = −3.665, p <.01). For grade II patients, the recovery time (t = −4.121, p <.01) and the disappearance of hypopyon (t = −4.291, p <.01) were significantly faster in the combination group. In grade Ι and II patients, the final visual acuity and the incidence of complications such as corneal neovascularization, cataract, and hyphema showed no differences in both groups. The survival curve showed that the healing rate of ulcers in the combination treatment group was faster than that in the conventional treatment group (χ2 = 14.332, p =.001). HOCI can accelerate the healing of fungal keratitis without obvious complications, indicating a promising future in the field of keratitis treatment. [ABSTRACT FROM AUTHOR]

Fungal keratitis (FK) is a severe infectious corneal disease. Since traditional eye drops exhibit poor dissolution and high corneal toxicity, the efficacy of current treatments for FK remains limited. It is needed to develop new approaches to control the cornea damage from FK. In this study, a nanobody (Nb) specific to β-glucan in the fungal cell wall was prepared. The conjugate of the Nb with natamycin (NAT), a traditional antifungal drug, was synthesized. Firstly, we found the Nb specific to β-glucan inhibited fungal growth by disrupting cell wall and biofilm formation.. In addition, the content of β-glucan in the fungal cell wall decreased after Nb treatment. The Nb also reduced the adhesion ability of fungal conidia to human corneal epithelial cells (HCECs). Further, we examined the difference between NAT and Nb-NAT in antifungal growth. Nb-NAT showed better antifungal effects than NAT which was caused by the interaction between Nb and β-glucan. Moreover, Nb concentration below 0.5 mg/mL did not affect the viability of HCECs. Nb-NAT had less cytotoxicity and ocular surface irritation than NAT. Nb specific to β-glucan attenuated Aspergillus fumigatus (A. fumigatus) virulence and relieved inflammatory responses in FK. Nb-NAT treatment of the cornea improved therapeutic effects compared with NAT. It decreased clinical scores and expression level of inflammatory factors. To our knowledge, this study is the first to report a Nb specific to β-glucan and Nb-NAT for the treatment of FK. These unique functions of the Nb specific to β-glucan and Nb-NAT would render it as an alternative molecule to control fungal infections including FK. Fungal keratitis is a corneal disease with a high rate of blindness. Due to the poor dissolution and high corneal toxicity exhibited by traditional eye drops, the efficacy of current therapeutic treatments for fungal keratitis (FK) remains limited. To enhance the therapeutic effect of natamycin in treating fungal keratitis, this study developed an innovative approach by preparing a β-glucan-specific nanobody and loading it with the antifungal drug natamycin. The β-glucan-specific nanobody has the ability to control both fungal pathogen invasion and inflammation, which can cause damage to the cornea in FK. The conjugation with the β-glucan-specific nanobody significantly increased the antifungal capacity of natamycin and reduced its toxicity. The further application of natamycin conjugated with the β-glucan-specific nanobody could be expanded to other diseases caused by fungal pathogen infections. [Display omitted] [ABSTRACT FROM AUTHOR]