The epidemiological features and laboratory results of fungal keratitis: a 10-year review at a referral eye care center in South India

Favorable outcome of Lasiodiplodia theobromae keratomycosis : a clinical case and systematic review

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.

Platelet-derived biomaterial controls aspergillus fumigatus keratitis by decreasing fungal burden: an in vivo study

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.

Etiopathology, Epidemiology, Diagnosis, and Treatment of Fungal Keratitis

Fungal keratitis (FK) is a severe ocular condition resulting from corneal infection that is prevalent in tropical countries, particularly in developing regions of Asia and Africa. Factors like corneal lens misuse, inappropriate steroid use, and diagnostic challenges have provoked the epidemic. FK causes significant vision impairment, scarring, and ocular deformities. Accurate pathological diagnosis is crucial for effective therapeutic intervention. Topical antifungal therapy with surface healing medications proves effective in preventing fungal-borne ulcers. Managing FK requires a comprehensive understanding of fungal pathogenesis, guiding formulation strategies and preventive measures to curb global ocular blindness. This review provides in-depth insights into FK, covering etiology, epidemiology, pathogenesis, therapeutic interventions, antifungal resistance, limitations, prevention, and future perspectives on ocular surface disease management.

A double-masked, sham-controlled trial of rose bengal photodynamic therapy for the treatment of fungal and acanthameoba keratitis: Rose Bengal Electromagnetic Activation with Green Light for Infection Reduction (REAGIR) Study

Background

Infectious keratitis secondary to fungus or acanthamoeba often has a poor outcome despite receiving the best available medical therapy. In vitro Rose Bengal Photodynamic therapy (RB-PDT) appears to be effective against fungal and acanthamoeba isolates.22,23 In one published series RB-PDT reduced the need for therapeutic penetrating keratoplasty in severe bacterial, fungal, and acanthameoba keratitis not responsive to medical therapy.

Methods

This international, randomized, sham and placebo controlled 2-arm clinical trial, randomizes patients with smear positive fungal and acanthameoba and smear negative corneal ulcers in a 1:1 fashion to one of two treatment arms: 1) Topical antimicrobial plus sham RB-PDT or 2) Topical antimicrobial plus RB-PDT.

Discussion

We anticipate that RB-PDT will improve best spectacle corrected visual acuity and also reduce complications such as corneal perforation and the need for therapeutic penetrating keratoplasty. This study will comply with the NIH Data Sharing Policy and Policy on the Dissemination of NIH-Funded Clinical Trial Information and the Clinical Trials Registration and Results Information Submission rule. Our results will be disseminated via clinicaltrials.gov website, meetings, and journal publications. Our data will also be available upon reasonable request.

Trial Registration

NCT, NCT05110001, Registered November 5, 2021. https://www.clinicaltrials.gov/study/NCT05110001.

Microbiological Profile of Culture-Positive Fungal Keratitis

PURPOSE

To examine the microbiological profile of cases of culture-positive fungal keratitis presenting to a tertiary eye care center in eastern India.

METHODS

Microbiology records of all culture-positive microbial keratitis patients presenting to L V Prasad Eye Institute, Bhubaneswar, between January 2020 and December 2021, were retrospectively reviewed. Collected data included smear results of culture-positive fungal or mixed infections, the species isolated, and the time taken for organisms to grow in each media.

RESULTS

Fungal keratitis formed 36% of all culture-positive microbial keratitis, whereas mixed infections (fungi and other organisms) formed 8.5%. The most common fungal species isolated was Fusarium spp. (25.8%). The most common bacteria involved in mixed infection with fungi was Staphylococcus spp. (54.8%). The positivity of potassium hydroxide+calcofluor white stain in detecting fungal filaments was 89.0% and that of Gram stain was 76.1%. Culture-positive cases of fungal keratitis showed most frequent growth on potato-dextrose agar (77.6%). A similar pattern was observed in culture-positive mixed infections (Sabouraud dextrose agar [SDA]: 84%). Most frequent growth of bacteria in mixed infections was seen in thioglycolate broth (54.7%). The shortest time to achieve significant fungal growth was observed in blood agar (BA) and chocolate agar (CA) (2.2/2.3 days, and 1.8/2 days for fungal keratitis and mixed infections, respectively). Filamentous hyaline fungi took the shortest time to achieve significant growth (2.8 days), whereas yeast forms took the longest (5 days).

CONCLUSION

This study highlights the importance of combined use of both solid and liquid culture media, especially potato dextrose agar (PDA)/SDA and CA, to arrive at a definitive diagnosis of fungal keratitis and possible bacterial co-infection, which forms a significant proportion of cases with fungal keratitis. In resource-poor laboratories, two culture media, either SDA or PDA, along with BA, may be plated to detect mixed infections. Examination of stained smears of corneal samples provides an inexpensive method of rapid diagnosis of fungal keratitis when culture media is not available.

Real-life experience on the effectiveness of conjunctival flap and amniotic membrane graft in the treatment of refractory fungal corneal ulcer

PURPOSE

To evaluate and compare the results of the conjunctival flap (CF) and cryopreserved amniotic membrane graft (AMG) in the management of fungal corneal ulcers either with complications or non-responsive to medical treatment.

STUDY DESIGN

A retrospective observational study.

METHODS

Medical records of 30 patients with culture-positive fungal corneal ulcer treated with either CF or AMG (15 eyes in each group) in real world settings were retrieved for analysis. After the surgical procedure, patients were followed up on days 1, 7, 14, 21, 30, 60, 90, 120, and 180 to explore the outcomes of the operations along with complications.

RESULTS

Infecting fungi were of genus Fusarium (n = 11), Aspergillus (n = 10), Mucor (n = 4) and Penicillium (n = 10). The most common indication was resistant ulcer with perforation. After the procedure, epithelization was completed in 11(73.33%) patients in the CF, and 13 patients in the (86.67%) AMG group. Visual acuity improvement was significantly better in the latter group (CF: 1 [6.67%] vs. AMG: 7 [46.67%], p = 0.023). Flap failure occurred in 4 patients (26.67%) from the CF and 2 (13.33%) from the AMG group. No significant differences were found between the two groups regarding success rate (p = 0.651), epithelialization time (p = 0.691), healing of corneal ulcer (p = 0.651), and postoperative stability (p = 0.651) of the flaps.

CONCLUSIONS

CF and AMG are both effective for the management of refractory fungal corneal ulcers. However, AMG appears to improve visual acuity better than CF.

Efficacy and Rapidity of Potassium Hydroxide Mount and Modified Chicago Sky Blue 6B Stain with Potassium Hydroxide in Fungal Keratitis Detection

PURPOSE

To compare the efficacy and rapidity of direct microscopic detection of fungal elements from corneal ulcers between 10% potassium hydroxide (KOH) and 1% Chicago Sky Blue 6B (CSB) in 10% KOH (CSB-KOH).

METHODS

Thirty patients with clinically suspected fungal keratitis were recruited. Participants with impending corneal perforation were excluded. Two slides were smeared with corneal ulcer scrapings from the ulcer's edge and base for comparison of fungal staining solutions. One slide was infused with KOH, and the other slide was filled with CSB-KOH. Additional scraping was collected for inoculation on Sabouraud dextrose agar for fungal culture. The sensitivity, specificity and rapidity of both stainings were analyzed.

RESULTS

The sensitivity of fungal culture, KOH, and CSB-KOH were 43.75% (95% confidence interval [CI], 19.75%-70.12%), 62.50% (95% CI, 35.43%-84.80%), and 87.50% (95% CI, 61.65%-98.45%), respectively. The specificity were 100% (95% CI, 69.15%-100%) of both stainings and fungal culture which analyzed from 16 fungal keratitis cases by laboratory and clinical diagnosis. Mean CSB-KOH examination time was quicker than KOH with the mean time difference of 5.6 minutes (95% CI, 3.22-7.98 minutes) and p-value < 0.001.

CONCLUSIONS

CSB-KOH was more effective and faster than KOH in detecting fungal elements from corneal ulcers. Therefore, CSB-KOH may be beneficial in diagnosing fungal keratitis and preventing blindness. Moreover, to the best of our knowledge, this is the first use of CSB stain in fungal keratitis detection.

Keratitis due to Lasiodiplodia theobromae successfully treated with voriconazole: A case series from Assam

Lasiodiplodia theobromae is a dematiaceous fungus which rarely causes keratitis and is mostly resistant to the commonly used antifungal drugs. Here, we report three cases of keratitis caused by L.theobromae from Assam. All the cases were successfully treated with 1% voriconazole and surgical debridement. To the best of our knowledge and literature search, this is the first case series of keratitis caused by L.theobromae reported from eastern India.

Variations in irradiation energy and rose bengal concentration for photodynamic antimicrobial therapy of fungal keratitis isolates

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.

Debulking corneal biopsy with tectonic amniotic membrane transplantation in refractory clinically presumed fungal keratitis

The treatment of fungal keratitis (FK) is challenging due to the subacute indolent course, and initial misdiagnosis. In this retrospective case series, we highlight both the diagnostic and therapeutic roles of corneal biopsy together with amniotic membrane transplantation (AMT) in patients with refractory clinically presumed FK. Debulking biopsy and tectonic AMT were performed during the initial presentation. Biopsy specimens were sent for KOH smears and cultures. After KOH smears confirmed the presence of fungal elements, topical voriconazole 1% was prescribed for the first 72 h then tailored according to the clinical response and the culture results. The outcome measures were complete resolution of infection and restoration of corneal integrity. Cases associated with culture proven bacterial keratitis were excluded. Twelve cases were included in the study. KOH smears confirmed the presence of fungal growth in all specimens. Cultures grew Aspergillus in 6/12 cases, sensitive to voriconazole (5/6) and amphotericin (3/6); Fusarium (4/12), sensitive to both voriconazole and amphotericin; and no growth in 2/12 cases. Amphotericin 0.15% eye drops were added to the 7 cases with proven sensitivity and to the remaining 2 culture negative cases. Gradual resolution of infection was seen in all cases after 35.6 ± 7.8 days. In FK, a debulking biopsy simultaneously with AMT help decrease the microbial load, suppress the inflammatory process, support the corneal integrity, confirm the presence of fungal pathogen.

From the diagnosis of infectious keratitis to discriminating fungal subtypes; a deep learning-based study

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.

Beauveria bassiana Keratitis: A Case Series and Review of Literature

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.

Lasiodiplodia theobromae keratitis: A rare tropical fungal keratitis in a non-tropical climate

Purpose

We present the clinical and histopathological findings of a geographically unique Lasiodiplodia theobromae fungal keratitis case in North Carolina. L. theobromae is a rare cause of fungal keratitis, and all but one of the 51 previously reported cases have occurred in patients living in the tropics.

Observations

A man in his early 50s developed L. theobromae keratitis after being struck in the left eye by a piece of debris while using a flexible-cord weed trimmer. Intracapsular lensectomy and penetrating keratoplasty were necessary when initial antimicrobial therapy was ineffective. The best-corrected visual acuity was 20/40 four years postoperatively.

Conclusions and Importance

Our patient is only the second example of L. theobromae keratitis in a patient living in a sub-tropical climate and the first case in the U.S.A. outside of Florida. Additional in-vitro antibiotic sensitivity testing and documentation of more clinical cases are needed to define the optimal therapy for Lasiodiplodia theobromae keratitis.

Risk factors for corneal ulcers: a population-based matched case-control study in Nepal

BACKGROUND/AIMS

We aimed to examine risk factors for corneal ulcer in a rural and peri-urban setting in Nepal.

METHODS

This population-based matched case-control study was nested in a cluster randomised trial in 24 village development committees in Nepal. Incidence density sampling was used to match incident corneal opacity cases to controls, matching on time of opacity, age, sex and location. Cases and controls were invited to participate in a survey of risk factors for corneal ulcer. Risk factors were evaluated using conditional logistic regression to account for matching.

RESULTS

Of the 540 participants with incident opacities identified in the trial, 433 were willing to participate in this substudy and matched to a control. Compared with controls, cases had lower odds of having any education vs no education (adjusted OR, aOR 0.60, 95% CI 0.39 to 0.94), working in non-manual labour occupations vs manual labour occupations (aOR 0.64, 95% CI 0.42 to 0.95) and preferring medical shops for ocular trauma versus eye care system centres (aOR 0.58, 95% CI 0.37 to 0.92). Cases had higher odds of protective goggle use versus no protection (aOR 3.8, 95% CI 1.3 to 11.0) and having an ocular injury vs none (aOR 7.7, 95% CI 4.3 to 13.6) compared with controls.

CONCLUSION

We found ocular injury, manual labour and lower education to be strongly associated with the development of corneal ulcer. Given the persistent burden of corneal blindness in this area, prevention efforts could target efforts to increase access to care in areas where these factors are common.

Demographic and microbiological profile of corneal ulcer patients presenting at a tertiary healthcare center of Eastern India during the COVID era: A hospital-based cross-sectional study

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.

Evaluation of 0.01% Hypochlorous Acid Eye Drops Combined with Conventional Treatment in the Management of Fungal Corneal Ulcers: Randomized Controlled Trial

PURPOSE

To evaluate the efficacy and safety of hypochlorous acid (HOCI) eye drops in the treatment of fungal keratitis.

METHODS

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.

RESULTS

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).

CONCLUSION

HOCI can accelerate the healing of fungal keratitis without obvious complications, indicating a promising future in the field of keratitis treatment.

TFOS Lifestyle: Impact of nutrition on the ocular surface

Nutrients, required by human bodies to perform life-sustaining functions, are obtained from the diet. They are broadly classified into macronutrients (carbohydrates, lipids, and proteins), micronutrients (vitamins and minerals) and water. All nutrients serve as a source of energy, provide structural support to the body and/or regulate the chemical processes of the body. Food and drinks also consist of non-nutrients that may be beneficial (e.g., antioxidants) or harmful (e.g., dyes or preservatives added to processed foods) to the body and the ocular surface. There is also a complex interplay between systemic disorders and an individual's nutritional status. Changes in the gut microbiome may lead to alterations at the ocular surface. Poor nutrition may exacerbate select systemic conditions. Similarly, certain systemic conditions may affect the uptake, processing and distribution of nutrients by the body. These disorders may lead to deficiencies in micro- and macro-nutrients that are important in maintaining ocular surface health. Medications used to treat these conditions may also cause ocular surface changes. The prevalence of nutrition-related chronic diseases is climbing worldwide. This report sought to review the evidence supporting the impact of nutrition on the ocular surface, either directly or as a consequence of the chronic diseases that result. To address a key question, a systematic review investigated the effects of intentional food restriction on ocular surface health; of the 25 included studies, most investigated Ramadan fasting (56%), followed by bariatric surgery (16%), anorexia nervosa (16%), but none were judged to be of high quality, with no randomized-controlled trials.

A knowledge-enhanced transform-based multimodal classifier for microbial keratitis identification

Microbial keratitis, a nonviral corneal infection caused by bacteria, fungi, and protozoa, is an urgent condition in ophthalmology requiring prompt treatment in order to prevent severe complications of corneal perforation and vision loss. It is difficult to distinguish between bacterial and fungal keratitis from image unimodal alone, as the characteristics of the sample images themselves are very close. Therefore, this study aims to develop a new deep learning model called knowledge-enhanced transform-based multimodal classifier that exploited the potential of slit-lamp images along with treatment texts to identify bacterial keratitis (BK) and fungal keratitis (FK). The model performance was evaluated in terms of the accuracy, specificity, sensitivity and the area under the curve (AUC). 704 images from 352 patients were divided into training, validation and testing set. In the testing set, our model reached the best accuracy was 93%, sensitivity was 0.97(95% CI [0.84,1]), specificity was 0.92(95% CI [0.76,0.98]) and AUC was 0.94(95% CI [0.92,0.96]), exceeding the benchmark accuracy of 0.86. The diagnostic average accuracies of BK ranged from 81 to 92%, respectively and those for FK were 89-97%. It is the first study to focus on the influence of disease changes and medication interventions on infectious keratitis and our model outperformed the benchmark models and reaching the state-of-the-art performance.

Oral voriconazole monotherapy for fungal keratitis: efficacy, safety, and factors associated with outcomes

Purpose

To provide preliminary data on the efficacy and safety of oral voriconazole (VCZ) as a primary treatment for fungal keratitis (FK).

Method

We performed a retrospective histopathological analysis of data on 90 patients with FK at The First Affiliated Hospital of Guangxi Medical University between September 2018 and February 2022. We recorded three outcomes: corneal epithelial healing, visual acuity (VA) improvement, and corneal perforation. Independent predictors were identified using univariate analysis, and multivariate logistic regression analysis was used to identify independent predictive factors associated with the three outcomes. The area under the curve was used to evaluate the predictive value of these factors.

Results

Ninety patients were treated with VCZ tablets as the only antifungal drug. Overall, 71.1% (n = 64) of the patients had extreme corneal epithelial healing, 56.7% (n = 51) showed an improvement in VA, and 14.4% (n = 13) developed perforation during treatment. Non-cured patients were more likely to have large ulcers (≥5 × 5 mm²) and hypopyon.

Conclusion

The results indicated that oral VCZ monotherapy was successful in the patients with FK in our study. Patients with ulcers larger than 5 × 5 mm² and hypopyon were less likely to respond to this treatment.

Automatic Diagnosis of Infectious Keratitis Based on Slit Lamp Images Analysis

Infectious keratitis (IK) is a common ophthalmic emergency that requires prompt and accurate treatment. This study aimed to propose a deep learning (DL) system based on slit lamp images to automatically screen and diagnose infectious keratitis. This study established a dataset of 2757 slit lamp images from 744 patients, including normal cornea, viral keratitis (VK), fungal keratitis (FK), and bacterial keratitis (BK). Six different DL algorithms were developed and evaluated for the classification of infectious keratitis. Among all the models, the EffecientNetV2-M showed the best classification ability, with an accuracy of 0.735, a recall of 0.680, and a specificity of 0.904, which was also superior to two ophthalmologists. The area under the receiver operating characteristics curve (AUC) of the EffecientNetV2-M was 0.85; correspondingly, 1.00 for normal cornea, 0.87 for VK, 0.87 for FK, and 0.64 for BK. The findings suggested that the proposed DL system could perform well in the classification of normal corneas and different types of infectious keratitis, based on slit lamp images. This study proves the potential of the DL model to help ophthalmologists to identify infectious keratitis and improve the accuracy and efficiency of diagnosis.

Characteristics of In Vitro Culture and In Vivo Confocal Microscopy in Patients with Fungal Keratitis in a Tertiary Referral Hospital in Central China

PURPOSE

To investigate the characteristics of in vitro culture and in vivo confocal microscopy (IVCM) in patients with fungal keratitis (FK) presented in a tertiary referral hospital in central China.

METHODS

In this noncomparative retrospective study, patients with the diagnosis of FK between October 2021 and November 2022 were reviewed. An IVCM and fungal culture (corneal scraping specimens) were performed, and the characteristics were analyzed.

RESULTS

During October 2021 and November 2022, 85 patients were diagnosed with FK. From 63 culture-positive cases, 8 species of fungus were identified. The proportions of isolated fungal species were Fusarium and Aspergillus equally accounting for 33.3% (21 of 63), Alternaria 9.5% (6 of 63), Curvularia 6.3% (4 of 63), Scedosporium apiospermum 6.3% (4 of 63), Paecilomyces lilacinus 3.2% (2 of 63), Exserohilum 3.2% (2 of 63), and Candida 4.8% (3 of 63), respectively. In positive culture cases, IVCM was found to be positive for hyphae or spores in 61 of 63 patients (96.8%). Different fungal species had a variety of cultural characteristics and IVCM manifestations.

CONCLUSIONS

In a tertiary referral hospital in central China, Fusarium species, Aspergillus species, and Alternaria species were the 3 most common isolated fungal pathogens, and the proportion of Aspergillus species was significantly higher than that in other regions of China. Careful lesion depth examination by IVCM and OCT should be taken before lamellar keratoplasty to avoid postoperative recurrence. Identifying the IVCM image and culture characteristics will facilitate rapid diagnosis and proper treatment, but IVCM cannot yet replace fungal cultures to distinguish between different fungal species.

Fungal keratitis in Iran: Risk factors, clinical features, and mycological profile

Introduction

This study was intended to investigate the clinical features and predisposing factors of fungal keratitis (FK), as well as molecular identification and antifungal susceptibility of causative agents in Tehran, Iran.

Methods

This cross-sectional study was carried out from April 2019 to May 2021. All fungi isolates were identified using conventional methods and were confirmed by DNA-PCR-based molecular assays. Matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) was used to identify yeast species. Minimum inhibitory concentrations (MIC) of eight antifungal agents were assessed according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) microbroth dilution reference method.

Results

Fungal etiology was confirmed in 86 (7.23%) of 1189 corneal ulcers. A significant predisposing factor for FK was ocular trauma caused by plant materials. Therapeutic penetrating keratoplasty (PKP) was required in 60.4% of cases. The predominant fungal species isolated was Fusarium spp. (39.5%) followed by Aspergillus spp. (32.5%) and Candida spp. (16.2%).

Discussion

The MIC results indicate that amphotericin B may be appropriate for treating FK caused by Fusarium species. FK caused by Candida spp. can be treated with flucytosine, voriconazole, posaconazole, miconazole, and caspofungin. In developing countries such as Iran, corneal infection due to filamentous fungi is a common cause of corneal damage. In this region, fungal keratitis is observed primarily within the context of agricultural activity and subsequent ocular trauma. Fungal keratitis can be managed better with understanding the "local" etiologies and antifungal susceptibility patterns.

Molecular characterization of fungal endophthalmitis and keratitis caused by yeasts

Candida species are the most common causes of sight-threatening fungal ocular infections in temperate regions of the world. Despite their relevance, little is known about the emergence of novel species and the molecular epidemiology of these infections. Here, we molecularly characterized 38 yeast isolates collected from patients diagnosed with endophthalmitis or keratitis at Massachusetts Eye and Ear from 2014 to 2021. Sequencing of the ITS1-5.8S-/ITS2 regions demonstrated that this population of yeasts was dominated by Candida spp. (37 out of 38; 97%), with 58% of the cases caused by C. albicans (n = 22) and the remaining by emerging non-albicans species, predominantly by C. parapsilosis (n = 8) and C. dubliniensis (n = 6). One isolate each was identified as C. tropicalis and Clavispora lusitaniae. Interestingly, all C. dubliniensis were isolated from endophthalmitis and most C. parapsilosis from keratitis. Multilocus sequence typing analysis of C. albicans showed a prevalence of CC-1 isolates that has DST69 as the putative founder, with 64% of them belonging to this clonal complex (CC). Isolates grouped within this cluster were more predominant in endophthalmitis (10 out of 14; 71%). One C. albicans CC-1 isolate was multi-azole resistant. In conclusion, we observed that nearly half of the ocular infections caused by yeasts are associated with C. albicans, with evidence for the emergence of non-albicans species that are differentially enriched in distinct ocular niches. Candida albicans isolates clustered within the predominant CC-1 group were particularly more common in endophthalmitis, demonstrating a potential pattern of ocular disease enrichment within this clade.

A 5-Year Retrospective Analysis of the Risk Factors, Treatment, and Prognosis of Patients With Fungal Keratitis in Heilongjiang, China

PURPOSE

To report the epidemiologic features, laboratory findings, and treatment outcomes of patients with fungal keratitis (FK) during a busy farming period (May, June, and September to November) in Heilongjiang Province, China.

DESIGN

Retrospective, observational case series.

METHODS

In total, 251 patients diagnosed with FK at the Eye Hospital, First Affiliated Hospital of Harbin Medical University, from 2017 to 2021 were identified. Medical records were retrospectively analyzed, and demographic features, risk factors, monthly distributions, clinical characteristics, laboratory findings, treatment strategies, and prognostic data were collected.

RESULTS

The number of FK cases in the busy farming period accounted for 74.1% (186/251) of the total. The mean patient age was 58.2±9.5 years. Males (66.7%) were more likely to develop FK than females (33.3%), and plant-related trauma was the main cause in 80.1% (149/186) of the cases. The most common causative fungal species was Fusarium (34.9%). In vivo confocal microscopy had the highest positivity rate for FK diagnosis (94.6%). The depth of hypopyon, depth of hyphae or spores, and infiltrate width were significantly positively correlated with delayed presentation.

CONCLUSIONS

Patients with a longer time of presentation to the hospital were more likely to undergo surgery because of topical medical therapy failure. The most important measures for FK prevention are the use of eye protection during outdoor work and visiting the hospital for treatment as soon as possible after eye injury.

Evaluation of antifungal susceptibility and clinical characteristics in fungal keratitis in a tertiary care center in North India

Purpose

To study the antifungal susceptibility of common corneal pathogenic fungi to antifungal agents in the North Indian population.

Methods

Prospective study of the antifungal sensitivity testing (natamycin, amphotericin B, voriconazole, itraconazole, fluconazole, posaconazole, caspofungin, micafungin) of fungal isolates from 50 cases of culture positive fungal keratitis by using E test method. Details noted included demographic data, visual acuity, clinical details, grade of keratitis, healing time, and success in medical management.

Results

Of 50 patients with fungal keratitis (mean age: 40.28 ± 16.77 years), 12 eyes healed within 3 weeks, 14 had a delayed healing response, and 24 had chronic keratitis. Among the 15 cases of Fusarium isolates, 93.3% were sensitive to natamycin, while 40% to amphotericin B; 66.6% to voriconazole, 13.4% to itraconazole and fluconazole each. 80% of Fusarium cases (n = 12) showed susceptibility to posaconazole. Among Aspergillus flavus isolates, 53.4% (n = 8) were sensitive to natamycin, with only 40% (n = 7) showing sensitivity to amphotericin B and good susceptibility to azoles. MIC against susceptible Fusarium spp. for natamycin was 3-16 μg/mL, amphotericin B: 1-8 μg/mL, voriconazole: 0.5-1.5 μg/mL, itraconazole: 0.5-12 μg/mL, posaconazole: 0.094-1.5 μg/mL. MIC against Aspergillus flavus was natamycin: 8-32 μg/mL, amphotericin B: 0.5-16 μg/mL, voriconazole: 0.025-4 μg/mL, itraconazole: 0.125-8 μg/mL, posaconazole: 0.047-0.25 μg/mL; against Aspergillus niger isolates, to natamycin was 6 μg/mL (n=1), amphotericin B 8-12 μg/mL (n = 3), voriconazole: 0.125-0.19 μg/mL (n = 3), itraconazole: 0.38-0.75 μg/mL, posaconazole: 0.064-0.19 μg/mL and against Aspergillus fumigatus (n = 1), was natamycin4 μg/mL, amphotericin B - 8 μg/mL, voriconazole 0.25 μg/mL, itraconazole 1 μg/mL, and posaconazole 0.19 μg/mL. MIC against susceptible Acremonium spp. for natamycin was 1.5-16 μg/mL, amphotericin B: 0.5-8 μg/mL, voriconazole: 0.19-3 μg/mL, itraconazole: 0.125 μg/mL, posaconazole: 0.125-0.5 μg/mL and against susceptible Curvularia was natamycin 0.75-4 μg/mL, amphotericin B 0.5-1 μg/mL, voriconazole 0.125-0.19 μg/mL, itraconazole 0.047-0.094 μg/mL, posaconazole 0.047-0.094 μg/mL. MIC against Mucor spp.+ Rhizopus spp. (n = 1) was natamycin: 8 μg/mL, amphotericin B: 0.75 μg/mL, posaconazole: 1.5 μg/mL. MIC against of Alternaria (n = 1) was voriconazole: 0.19 μg/mL, posaconazole: 0.094 μg/mL. MIC against Penicillium (n=1) was natamycin: 8 μg/mL, voriconazole: 0.25 μg/mL, itraconazole: 0.5 μg/mL, and Posaconazole: 0.125 μg/mL.

Conclusion

Our observations highlight the variations in susceptibility to antifungal agents. Posaconazole seems to be effective with low MIC against common corneal pathogenic fungal isolates.

Ophthalmic trauma: the top 100 cited articles in Ophthalmology journals

OBJECTIVES

To analyze the top 100 cited papers on ophthalmic trauma.

METHODS

A literature search of Ophthalmology journals within the ISI Web of Science database for the most cited papers related to ophthalmic trauma.

RESULTS

The most cited articles were published between 1943 and 2013, the greatest number being published in 2000. Ophthalmology (45), Archives of Ophthalmology (17), and the American Journal of Ophthalmology (15) published most of the articles. The institutions with the highest number of publications were Wilmer Eye Institute (10) and Massachusetts Eye and Ear Infirmary (7). Sixty-seven percent of the articles originated from the USA. The most common type of trauma studied was non-open-globe injuries and the most frequent topic studied were pathological conditions secondary to trauma (34), particularly endophthalmitis (8), and optic neuropathy (6). Articles presenting a standardized classification system for eye injury received the highest average of citations per publication. Types of research most frequently cited were observational clinical studies (62) and epidemiological studies (30); the least frequent were clinical trials (2).

CONCLUSION

This bibliographic study provides a historical perspective of the literature and identifies trends within the most highly influential papers on ophthalmic trauma. Many of these articles emerged within the past three decades and came from Ophthalmology journals that remain high impact to this day. Clinical trials have been difficult to conduct and are lacking, reflecting a critical need in ophthalmic trauma research, as most of our understanding of ophthalmic trauma comes from observational and epidemiological studies.

Gallic Acid Ameliorates Aspergillus Fumigatus Keratitis Through Reducing Fungal Load and Suppressing the Inflammatory Response

Purpose

The purpose of this study was to explore the antifungal and anti-inflammatory effects of gallic acid (GA) on Aspergillus fumigatus (A. fumigatus) keratitis.

Methods

CCK-8 assay and Draize eye test were used to determine the non-cytotoxic concentration of GA in RAW264.7 cells and an A. fumigatus keratitis mouse model. The antifungal effects of GA were analyzed using minimal inhibitory concentration (MIC), biofilm formation test, fungal adherence assay, calcofluor white staining, and propidium iodide staining. The therapeutic effects of GA were estimated by slit lamp photographs, clinical score, hematoxylin and eosin (H&E) staining, and Periodic acid-Schiff staining in vivo. Immunofluorescence staining and myeloperoxidase assay were conducted to identify neutrophil infiltration and activity. RT-PCR, ELISA, and Western blot were performed to detect the expression of pro-inflammatory cytokines and Nrf2/HO-1.

Results

In HCECs and A. fumigatus keratitis mouse model, GA at 100 µg/mL did not affect cell viability, thus this concentration was applied to subsequent experiments. In vitro, GA significantly inhibited A. fumigatus growth, biofilm formation, and adhesion. In vivo, 100 µg/mL GA alleviated the severity of fungal keratitis (FK) by repressing fungal load, reducing neutrophil infiltration, and lowering MPO activity. Besides, the expression of IL-1β, TNF-α, LOX-1, and COX-2 was inhibited, whereas Nrf2 and HO-1 expression was enhanced at both mRNA and protein levels in the 100 µg/mL GA treated group in comparison to PBS control.

Conclusions

GA ameliorates FK severity through inhibiting A. fumigatus load, reducing neutrophils infiltration, downregulating the expression of pro-inflammatory cytokines, and enhancing the Nrf2/HO-1 pathway, which provides new insight into A. fumigatus keratitis treatment.

Pyrenocheata unguis-hominis: A new cause of fungal keratitis in a contact lens wearer

Purpose

Observations

Conclusions

Filamentous Fungal Keratitis in Greece: A 16-Year Nationwide Multicenter Survey

In a multicenter, prospective study of filamentous fungal keratitis in Greece, predisposing factors, etiology, treatment practices, and outcome, were determined. Corneal scrapings were collected from patients with clinical suspicion of fungal keratitis, and demographic and clinical data were recorded. Fungal identification was based on morphology, molecular methods, and matrix assisted laser desorption ionization time-of-flight mass-spectrometry. A total of 35 cases were identified in a 16-year study period. Female to male ratio was 1:1.7 and median age 48 years. Corneal injury by plant material, and soft contact lens use were the main risk factors (42.8% and 31.4%, respectively). Trauma was the leading risk factor for men (68.1%), contact lens use (61.5%) for women. Fusarium species were isolated more frequently (n = 21, 61.8%). F. solani was mostly associated with trauma, F. verticillioides and F. proliferatum with soft contact lens use. Other fungi were: Purpureocillium lilacinum (14.7%), Alternaria (11.8%), Aspergillus (8.8%), and Phoma foliaceiphila, Beauveria bassiana and Curvularia spicifera, one case each. Amphotericin B and voriconazole MIC₅₀s against Fusarium were 2 mg/L and 4 mg/L respectively. Antifungal therapy consisted mainly of voriconazole locally or both locally and systemically, alone or in combination with liposomal AmB. Cure/improvement rate with antifungal therapy alone was 52%, keratoplasty was required in 40% of cases, and enucleation in 8%. In conclusion, filamentous fungal keratitis in Greece is rare, but with considerable morbidity. A large proportion of cases resulted in keratoplasty despite appropriate antifungal treatment.Kindly confirm the given name and family name are correctly identified for all authros.ConfirmedJournal instruction requires a city and country for affiliations; however, these are missing in affiliations 1, 3, 4, 5, 6, 13. Please verify if the provided city and country are correct and amend if necessary.All provided cities and countries are correct.

Trends in the Microbiological Spectrum of Nonviral Keratitis at a Single Tertiary Care Ophthalmic Hospital in India: A Review of 30 years

PURPOSE

The aims of this study were to assess the trends in microorganisms from patients with infectious keratitis and to assess their antibiogram patterns at a tertiary eye care center in India.

METHODS

In this retrospective observational case series, microbiological records of all corneal ulcers were reviewed from 1991 to 2020 and assessed for trends in keratitis and antibiotic susceptibility using the χ2 test.

RESULTS

Of the total of 51,747 patients, 51.13% were culture positive. A decrease in bacteria was noted from 56% to 38%, with a parallel increase in fungal isolates from 24% to 51%. Gram-positive bacteria accounted for 70.8% of the total bacteria, a trend in rise of Streptococcus pneumoniae (31%) and a decreasing trend in prevalence of Staphylococcus epidermidis was observed over 30 years. Pseudomonas aeruginosa (55.5%) was the most prevalent gram-negative pathogen, whereas Fusarium spp. (33.1%) and Aspergillus spp. (32.4%) were the most common fungal isolates. The susceptibility of gram-positive organisms to cefazolin decreased from 95.5% to 66% (P = 0.0001), amikacin from 88% to 55% (P= 0.0001), and vancomycin from 98.9% to 90.7% (P < 0.05). A similar decrease in susceptibility was also significant for gram-negative organisms with piperacillin/tazobactam and chloramphenicol (P < 0.05). A significant trend toward increasing resistance against fluoroquinolones was also observed for ciprofloxacin (gram-positive organisms: 16% to 50%; gram-negative organisms: 11.5% to 18.7%), gatifloxacin (38% to 47%), and moxifloxacin (9.4% to 29%).

CONCLUSIONS

The spectrum of keratitis has changed, and fungus is now the predominant etiology. An increasing trend in resistance to all antibiotics studied would affect the empiric treatment, also suggesting regular surveillance.

Mycobiomes of the Ocular Surface in Bacterial Keratitis Patients

Inflammation of the cornea is known as keratitis, and bacteria, fungi, protozoans, and viruses are the etiological agents of this disease. Delayed treatment of keratitis could result in loss of vision and, under certain severity conditions, the removal of an eye and its associated structures. In the current study, the ocular surface (conjunctiva and cornea) mycobiomes of individuals with bacterial keratitis were compared with the ocular mycobiome (conjunctiva) of healthy individuals, free of any ocular morbidity. Mycobiomes were generated through NGS approach using conjunctival swabs and corneal scrapings as the source of DNA from which ITS2 was amplified and sequenced, as a proxy to identify fungi. The results indicated significant changes in the alpha-diversity indices and in the abundance at the phylum and genera level. Hierarchical clustering using a heatmap showed that the mycobiomes were different. Furthermore, NMDS plots also differentiated the mycobiomes in the three cohorts, implying dysbiosis in the mycobiomes of the conjunctivae and corneal scrapings of bacterial keratitis individuals compared to control individuals. A preponderance of negative interactions in the hub genera in the conjunctival swabs of bacterial keratitis individuals compared to healthy controls further re-emphasized the differences in the mycobiomes. The dysbiotic changes at the genera level in conjunctivae and corneal scrapings of bacterial keratitis individuals are discussed with respect to their possible role in causing or exacerbating ocular surface inflammation. These results demonstrate dysbiosis in the ocular mycobiome in bacterial keratitis patients compared to healthy controls for the first time.

Village-integrated eye workers for prevention of corneal ulcers in Nepal (VIEW study): a cluster-randomised controlled trial

BACKGROUND

Corneal ulcers are a common cause of blindness in low-income and middle-income countries, usually resulting from traumatic corneal abrasions during agricultural work. Antimicrobial prophylaxis of corneal abrasions can help prevent corneal ulcers, but delays in the initiation of therapy are frequent. We aimed to assess whether a community-based programme for corneal ulcer prevention would reduce the incidence of corneal ulceration.

METHODS

A cluster-randomised trial was performed in village development committees (VDCs) in Nepal. VDCs in the catchment area of Bharatpur Eye Hospital, Nepal with less than 15 000 people were eligible for inclusion. We randomly assigned (1:1) VDCs to either an intervention group or a control group. In the intervention VDCs, existing female community health volunteers (FCHVs) were trained to diagnose corneal abrasions and provide a 3-day course of ophthalmic antimicrobials to their patients. In the control VDCs, FCHVs did not provide this intervention. Participants were not masked given the nature of the intervention. Both groups were followed up for 3 years for photographic evidence of corneal ulceration. The primary outcome was the incidence of corneal ulceration, determined by masked assessment of corneal photographs. The analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, NCT01969786.

FINDINGS

We assessed 112 VDCs, of which 24 were enrolled. The study was performed between Feb 4, 2014, and Oct 20, 2017. 12 VDCs were randomly assigned to the intervention group and 12 to the control group. 252 539 individuals were included in the study (130 579 in the intervention group and 121 960 in the control group). FCHVs diagnosed and provided antimicrobials for 4777 corneal abrasions. The census identified 289 corneal ulcers among 246 893 person-years in the intervention group (incidence 1·21 cases [95% CI 0·85-1·74] per 1000 person-years) and 262 corneal ulcers among 239 170 person-years in the control group (incidence 1·18 cases [0·82-1·70] per 1000 person-years; incidence rate ratio 1·03 [95% CI 0·63-1·67]; p=0·93). Medication allergy was self-reported in 0·2% of participants.

INTERPRETATION

We did not detect a reduction in the incidence of corneal ulceration during the first 3 years of a community-based corneal ulcer prevention programme. Further study might be warranted in more rural areas where basic eye care facilities are not available.

FUNDING

National Eye Institute.

Microbial Keratitis in Nepal: Predicting the Microbial Aetiology from Clinical Features

Fungal corneal infection (keratitis) is a common clinical problem in South Asia. However, it is often challenging to distinguish this from other aetiologies, such as bacteria or acanthamoeba. In this prospective study, we investigated clinical and epidemiological features that can predict the microbial aetiology of microbial keratitis in Nepal. We recruited patients presenting with keratitis to a tertiary eye hospital in lowland eastern Nepal between June 2019 and November 2020. A structured assessment, including demographics, history, and clinical signs, was carried out. The aetiology was investigated with in vivo confocal microscopy and corneal scrape for microscopy and culture. A predictor score was developed using odds ratios calculated to predict aetiology from features. A fungal cause was identified in 482/642 (75.1%) of cases, which increased to 532/642 (82.9%) when including mixed infections. Unusually, dematiaceous fungi accounted for half of the culture-positive cases (50.6%). Serrated infiltrate margins, patent nasolacrimal duct, raised corneal slough, and organic trauma were independently associated with fungal keratitis (p < 0.01). These four features were combined in a predictor score. The probability of fungal keratitis was 30.1% if one feature was present, increasing to 96.3% if all four were present. Whilst microbiological diagnosis is the "gold standard" to determine the aetiology of an infection, certain clinical signs can help direct the clinician to find a presumptive infectious cause, allowing appropriate treatment to be started without delay. Additionally, this study identified dematiaceous fungi, specifically Curvularia spp., as the main causative agent for fungal keratitis in this region. This novel finding warrants further research to understand potential implications and any trends over time.

Fungi of the human eye: Culture to mycobiome

The focus of the current review is multi-fold and compares the diversity and abundance of fungi on the ocular surface by the conventional culture-based method with the more sensitive, high throughput, culture-independent NGS method. The aim is to highlight the existence of a core ocular mycobiome and explore the transition of the ocular fungal microbiota from the normal eye to the diseased eye. PubMed, Google Scholar and Medline were used to search for publications and reviews related to cultivable fungi and the mycobiome of the normal and diseased eye. The conventional cultivable approach and the NGS approach confirm that the eye has its own mycobiome and several confounding factors (age, gender, ethnicity etc.) influence the mycobiome. Further, dysbiosis in the mycobiome appears to be associated with ocular diseases and thus impacts the health of the human eye. Considering that the mycobiome of the eye is influenced by several confounding factors and also varies with respect to the disease status of the eye there is a need to extensively explore the mycobiome under different physiological conditions, different ethnicities, geographical regions etc. Such studies would unravel the diversity and abundance of the mycobiomes and contribute to our understanding of ocular health. Research focused on ocular mycobiomes may eventually help to build a targeted and individualized treatment.

Ocular pathogens and antibiotic resistance in microbial keratitis over three years in Harbin, Northeast China

Purpose

Understanding the spectrum of ocular pathogens in a given geographic region is important for devising appropriate practical treatment. Therefore, we examined the pathogen spectrum and antibiotic resistance of microbial keratitis in northeast China.

Methods

In this retrospective observational study, we reviewed the microbiology laboratory records of patients diagnosed with microbial keratitis in a tertiary eye hospital in Harbin, northeast China, between 2017 and 2019, and analysed the pathogen spectrum and antibiotic susceptibility.

Results

We collected 462 specimens, of which 282 exhibited positive cultures. Among these cultures, 257 were bacterial and 25 were fungal. Of the 257 bacterial isolates, 214 (83.27%) were gram positive whereas 43 (16.73%) were gram negative. The most prevalent gram‐positive pathogen was coagulase‐negative staphylococcus (CoNS; 58.37%), followed by Staphylococcus aureus (S. aureus; 20.62%) and Streptococcus pneumoniae (2.33%). Of the gram‐negative bacterial isolates, 10 were Pseudomonas aeruginosa (3.89%). The most frequently detected ocular pathogens from fungal isolates were Fusarium species (40%). We also found more culture‐positive cases of bacterial keratitis in summer. Overall, 16.98% S. aureus and 64.00% CoNS isolates were methicillin resistant. These methicillin‐resistant bacteria were also more likely to be resistant to other antibiotics, with multidrug resistance found in 77.78% methicillin‐resistant S. aureus and 90.63% methicillin‐resistant CoNS. However, all gram‐positive isolates were sensitive to vancomycin and linezolid.

Conclusion

Coagulase‐negative staphylococcus are the most common ocular pathogens in northeast China. We also show the prevalence of methicillin resistance and concurrent multidrug resistance among staphylococcal isolates. Monitoring the patterns of antimicrobial resistance could help in the management selection.

Infectious Keratitis: An Update on Role of Epigenetics

Epigenetic mechanisms modulate gene expression and function without altering the base sequence of DNA. These reversible, heritable, and environment-influenced mechanisms generate various cell types during development and orchestrate the cellular responses to external stimuli by regulating the expression of genome. Also, the epigenetic modifications influence common pathological and physiological responses including inflammation, ischemia, neoplasia, aging and neurodegeneration etc. In recent past, the field of epigenetics has gained momentum and become an increasingly important area of biomedical research As far as eye is concerned, epigenetic mechanisms may play an important role in many complex diseases such as corneal dystrophy, cataract, glaucoma, diabetic retinopathy, ocular neoplasia, uveitis, and age-related macular degeneration. Focusing on the epigenetic mechanisms in ocular diseases may provide new understanding and insights into the pathogenesis of complex eye diseases and thus can aid in the development of novel treatments for these diseases. In the present review, we summarize the clinical perspective of infectious keratitis, role of epigenetics in infectious keratitis, therapeutic potential of epigenetic modifiers and the future perspective.

Fungal Endophthalmitis: A Comprehensive Review

Endophthalmitis is a serious ophthalmologic condition involving purulent inflammation of the intraocular spaces. The underlying etiology of infectious endophthalmitis is typically bacterial or fungal. The mechanism of entry into the eye is either exogenous, involving seeding of an infectious source from outside the eye (e.g., trauma or surgical complications), or endogenous, involving transit of an infectious source to the eye via the bloodstream. The most common organism for fungal endophthalmitis is Candida albicans. The most common clinical manifestation of fungal endophthalmitis is vision loss, but other signs of inflammation and infection are frequently present. Fungal endophthalmitis is a clinical diagnosis, which can be supported by vitreous, aqueous, or blood cultures. Treatment involves systemic and intravitreal antifungal medications as well as possible pars plana vitrectomy. In this review, we examine these essential elements of understanding fungal endophthalmitis as a clinically relevant entity, which threatens patients’ vision.

Fungal Keratitis in a Tertiary Hospital in Malaysia

Background

Fungal keratitis is one of the commonest causes of corneal blindness in developing countries including Malaysia. We aim to evaluate the sociodemographic background, clinical features, predisposing factors, laboratory findings, management, complications, and visual outcome of patients with fungal keratitis in a tertiary hospital in Malaysia.

Methods

A retrospective review of medical and microbiology records of all patients treated for corneal ulcer from 2015 to 2019 at Hospital Sultanah Bahiyah was performed. Sociodemography, predisposing risk factors, clinical characteristics, causative organisms, and final visual outcome were analyzed.

Results

We identified 103 patients with a diagnosis of fungal keratitis. The majority of the patients were of Malay ethnicity (85.4%) and male gender (81.6%), with an age range of 21 to 60 years (94.1%). Ocular trauma was the main predisposing factor in 82 (79.6%) patients. Poor visual improvement was observed in groups with ulcer more than 4mm (67.5%), presence of hypopyon (50.9%), and high intraocular pressure (75.0%) upon presentation. Fusarium spp. (19.4%) was the commonest fungus isolated followed by Aspergillus spp. (5.8%). All patients were prescribed either topical, oral, intracameral, or combined therapy, whereas 20 (19.4%) patients required surgical intervention, of which 16 (15.5%) underwent penetrating keratoplasty and three (2.9%) required evisceration.

Conclusion

The epidemiological, socioeconomic, and predisposing factors may facilitate timely diagnosis and prompt treatment to achieve a better visual outcome and minimize complications including corneal blindness.

Fungal Keratitis: Diagnostic Characteristics of the Potassium Hydroxide Preparation With Calcofluor White in Northern California

PURPOSE

The incidence of fungal keratitis demonstrates significant geographic and climatic variation. We report on the characteristics of the potassium hydroxide/calcofluor white (KOH-CFW) preparation observed at a tertiary center in Northern California, a region with a low incidence of fungal keratitis.

METHODS

Culture-proven cases of microbial keratitis during a 5-year period were retrospectively reviewed. The sensitivity, specificity, and posttest probabilities were determined for the KOH-CFW assay. These results were compared with documented clinical impression and values reported in the literature.

RESULTS

Three hundred three of 368 episodes of microbial keratitis during the study period documented the results of a fungal culture, KOH-CFW assay, and a clinical impression. Twenty-one (6.9%) of these cultures were positive for fungal organisms. The sensitivity and specificity of the KOH-CFW test were 29% and 93%, respectively. Clinicians' initial clinical impression based solely on patients' history and examination, without the aid of any histopathologic or biochemical test results, demonstrated a sensitivity and specificity of 33% and 89%, respectively.

CONCLUSIONS

The observed sensitivity and specificity of the KOH-CFW preparation are significantly lower than many previously reported values. In regions with low incidence of fungal keratitis, the KOH-CFW preparation may have diagnostic performance similar to that of the clinical impression formed only on the basis of history and physical examination.

Breaking the mold: a case of recalcitrant eyelid subconjunctival infection by Exophilia Phaeomuriformis

While a rare ophthalmic pathogen, infections from Exophilia spp. are increasingly identified and have been associated with catastrophic vision loss. In this case report we present a previously undescribed manifestation of the melanin-producing fungus Exophilia Phaeomuriformis to the lower eyelid, establish an effective treatment, and review related cases. Previous cases of ophthalmic E. Phaeomuriformis were confined to the cornea and included iatrogenic tissue trauma. This case shares neither associations however includes a remote SJS history that likely led to changes in conjunctival tissue integrity. Previous cases of Exophilia spp. infecting the eyelid both included surgical source control and adjuvant antibiotic. In this case, topical therapy was deferred due to SJS-related ocular cicatricial disease. Fortunately, a full resolution was achieved with surgical resection and oral antifungal treatment.

A Case of Black Fungal Keratitis Caused by Biatriospora mackinnonii

PURPOSE

To report a novel case of fungal keratitis caused by Biatriospora mackinnonii (Pyrenochaeta mackinnonii), a dematiaceous fungus (black fungus) that rarely causes dermatological infection, in a patient treated for ocular cicatricial pemphigoid.

METHODS

An 81-year-old patient with ocular cicatricial pemphigoid was referred to our hospital because of persistent corneal epithelial defects in his left eye. On examination, a slightly elevated dark lesion in the middle of the erosion and hypopyon was observed in that eye, with smear examination of the obtained specimen revealed a filamentous fungal-like material. Initially, treatment included miconazole and fluconazole ophthalmic solution eye drops, natamycin ophthalmic ointment, and systemic voriconazole, followed surgical scraping of the mass, an anterior chamber lavage, and a subconjunctival injection of miconazole. However, the focus had resistance to the treatment and finally led to corneal perforation; hence, therapeutic penetrating keratoplasty (PKP) was subsequently performed.

RESULTS

Mycological testing revealed that the lesions were Candida parapsiliosis and black fungus, with the black fungus classified as B. mackinnonii via DNA sequencing of the internal transcribed spacer and the D1/D2 domains of the 28S rRNA gene. Fungal keratitis caused by B. mackinnonii was resistant to the antifungal drugs, yet was ameliorated by PKP, with no recurrence of fungal keratitis for more than 2 years postoperative.

CONCLUSIONS

To the best of our knowledge, this is the first reported case of fungal keratitis caused by B. mackinnonii; however, in this case, PKP surgery resulted in a favorable outcome.

Predictive Factors for Resolution of Dematiaceous Fungal Keratitis

PURPOSE

To ascertain the clinicomicrobiological correlation and evaluate the prognostic factors associated with medical resolution in cases of Curvularia, Alternaria, and Scedosporium keratitis.

METHODS

A retrospective review of clinical and microbiological records of culture-proven cases of Curvularia, Alternaria, and Scedosporium keratitis from 2017 to 2019 was performed. Multivariate logistic regression analyses were performed to assess the predictive factors for medical resolution.

RESULTS

There were a total of 79 eyes of 79 patients. Among these, there were 56 (70.8%), 15 (18.9%), and 8 (10.1%) patients with Curvularia, Scedosporium, and Alternaria keratitis, respectively. Clinical resolution with medical treatment was achieved in 46 of 56 (82.1%) patients with Curvularia keratitis, 8 of 15 (53.3%) patients with Scedosporium, and 7 of 8 (87.5%) patients with Alternaria keratitis. In comparison between Curvularia and Scedosporium, macroscopic pigmentation [18/56 (32.1%)] of anterior stromal plaque-like infiltrate [20/56 (35.7%)] was clinically more in cases with Curvularia, whereas larger diameter of the infiltrate, P = 0.002, posterior stromal infiltrate (40%), P = 0.03, and hypopyon, P = 0.009, were more common with Scedosporium. Multivariate logistic regression analysis, by backward elimination, showed that maximum dimension of the infiltrate (P = 0.01; odds ratio = 0.52, 95% confidence interval, 0.31-0.86) and presence of a hypopyon (P = 0.02; odds ratio = 0.12, 95% confidence interval, 0.02-0.71) were significant factors that were not favoring medical resolution.

CONCLUSIONS

Larger size of the infiltrate, posterior stromal involvement, and presence of a hypopyon are poor prognostic indicators among all 3 species. Variation in species is not a predictor of clinical resolution.

The Role of SREC-Ⅰ in Innate Immunity to Aspergillus fumigatus Keratitis

Purpose

To determine the role of scavenger receptor expressed by endothelial cell-1 (SREC-Ⅰ) in vitro and in a mouse model of Aspergillus fumigatus keratitis.

Methods

SREC-Ⅰ mRNA and protein expression were tested in both normal and A fumigatus stimulated human corneal epithelial cells (HCECs). Immunofluorescence was used to detect SREC-Ⅰ expression in human corneas with or without A fumigatus infection. HCECs were incubated with SREC-Ⅰ small interfering RNA, then the mRNA levels of LOX-1, IL-1β, and TNF-α were detected after A fumigatus stimulation. A mouse fungal keratitis (FK) model was established and SREC-Ⅰ mRNA and protein expression were detected by RT-PCR, Western blot and immunofluorescence. The severity of FK was evaluated by clinical score. CLCX1, LOX-1, IL-1β, and TNF-α mRNA expression levels were tested before and after anti-SREC-Ⅰ treatment.

Results

SREC-Ⅰ expressed in normal and A fumigatus treated HCECs and human corneal epithelium. In vitro experiment showed that SREC-Ⅰ mRNA and protein levels were significantly increased after A fumigatus stimulation. SREC-Ⅰ small interfering RNA treatment inhibited the expressions of LOX-1, IL-1β, and TNF-α in HCECs. The expressions of CLCX1, LOX-1, IL-1β, and TNF-α were elevated in mice with A fumigatus keratitis, which could be decreased by SREC-Ⅰ-neutralizing antibody treatment.

Conclusions

SREC-Ⅰ is a key mediator in inflammatory response induced by A fumigatus keratitis. SREC-Ⅰ blockade could be a potential therapeutic approach for FK.

The Clinical Features and Prognostic Factors for Treatment Outcomes of Dematiaceous Fungal Keratitis over 9 Years at a Tertiary Eye Care in Northern Thailand

Dematiaceous fungal keratitis is an important etiology of visual loss, particularly in an agricultural society. From a retrospective review of medical records from 2012 to 2020, 50 keratitis cases of cultured-positive for dematiaceous fungi were presented at a tertiary care hospital in Northern Thailand. The study aimed to identify the isolated causative dematiaceous species using the PCR technique and to explore their related clinical features, including treatment prognoses. Sequencing of the amplified D1/D2 domains and/or ITS region were applied and sequenced. Of the 50 dematiaceous fungal keratitis cases, 41 patients were males (82%). In most cases, the onset happened during the monsoon season (June to September) (48%). The majority of the patients (72%) had a history of ocular trauma from an organic foreign body. The most common species identified were Lasiodiplodia spp. (19.35%), followed by Cladosporium spp. and Curvularia spp. (12.90% each). About half of the patients (52%) were in the medical failure group where surgical intervention was required. In summary, ocular trauma from an organic foreign body was the major risk factor of dematiaceous fungal keratitis in Northern Thailand. The brown pigmentation could be observed in only 26%. Significant prognostic factors for medical failure were visual acuity at presentation, area of infiltrate, depth of the lesions, and hypopyon.

Eye Infections Caused by Filamentous Fungi: Spectrum and Antifungal Susceptibility of the Prevailing Agents in Germany

Fungal eye infections can lead to loss of vision and blindness. The disease is most prevalent in the tropics, although case numbers in moderate climates are increasing as well. This study aimed to determine the dominating filamentous fungi causing eye infections in Germany and their antifungal susceptibility profiles in order to improve treatment, including cases with unidentified pathogenic fungi. As such, we studied all filamentous fungi isolated from the eye or associated materials that were sent to the NRZMyk between 2014 and 2020. All strains were molecularly identified and antifungal susceptibility testing according to the EUCAST protocol was performed for common species. In total, 242 strains of 66 species were received. Fusarium was the dominating genus, followed by Aspergillus, Purpureocillium, Alternaria, and Scedosporium. The most prevalent species in eye samples were Fusarium petroliphilum, F. keratoplasticum, and F. solani of the Fusarium solani species complex. The spectrum of species comprises less susceptible taxa for amphotericin B, natamycin, and azoles, including voriconazole. Natamycin is effective for most species but not for Aspergillus flavus or Purpureocillium spp. Some strains of F. solani show MICs higher than 16 mg/L. Our data underline the importance of species identification for correct treatment.

Fungal Keratitis in Northern Thailand: Spectrum of Agents, Risk Factors and Putative Virulence Factors

Fungal keratitis (FK) is a serious ocular infection that can result in various degrees of vision loss, including blindness. The aim of the study was to identify and retrospectively review all FK cases diagnosed between August 2012 and December 2020 at a tertiary care hospital in northern Thailand with a specific focus on epidemiologic features, including season, patient sex and age, the spectrum of pathogens, and presence of certain putative virulence factors. Of 1237 patients with corneal ulcers, 294 (23.8%) were confirmed by direct microscopic examination and/or fungal culture. For the positive cases, direct examinations of Calcofluor white (CW) stains and KOH mounts were found in 97.3% (286/294) and 76.5% (225/294), respectively (p < 0.05). Of the cases diagnosed by microscopy and culture, fungi were isolated in 152 (51.7%), with Fusarium spp. being the most frequently identified (n = 69, 45.5%) followed by dematiaceous fungi (n = 45, 29.6%) and Aspergillus spp. (n = 18, 11.8%). The incidence of FK was higher in the rainy season of July to October. The mean age was 54.4 ± 14.4 (SD) years, with a range of 9–88 years. Males (75.8%) were affected significantly more than females (24.2%) (p < 0.05). Of 294 patients, 132 (44.9%) were middle-aged adults (41–60 years) and 107 (36.4%) were older than 60 years. Trauma to the eye by soil or vegetative matter were the most common preceding factors (188/294; 64.0%). We assessed two virulence factors. First, 142 of the 152 culture-positive FK cases were due to molds, indicating that hyphal morphogenesis is extremely important in disease. We also demonstrated that fungal melanization occurs in the molds during the course of FK by applying a melanin-specific monoclonal antibody (MAb) that labeled fungal elements in corneal samples of patients, and melanin particles derived from the hyphae were also recovered after treatment of the samples with proteolytic enzymes, denaturant and hot concentrated acid. In summary, we demonstrate that northern Thailand has a high rate of FK that is influenced by season and males engaged in outside activities are at highest risk for disease. Moulds are significantly more commonly responsible for FK, in part due to their capacity to form hyphae and melanins. Future studies will examine models of fungal corneal interactions and assess additional factors of virulence, such as secreted enzymes, to more deeply decipher the pathogenesis of FK.

Drug reservoir function of voriconazole impregnated human amniotic membrane: An in vitro study

Purpose:

Earlier our group has demonstrated the drug reservoir function of the human amniotic membrane (HAM) using stable moxifloxacin and fortified cefazolin ophthalmic formulations and found it as a suitable tool to deliver drugs for an extended duration. The purpose of this study was to evaluate the extended-release kinetics of voriconazole from the impregnated human amniotic membrane (HAM) in vitro.

Methods:

HAM buttons were incubated with freshly prepared 1% topical ophthalmic formulation of voriconazole for 5 different exposure time to investigate the ideal exposure time for the extended-release of voriconazole from HAM. The drug release kinetics was studied in simulated tear fluid for 5 weeks and the amount of voriconazole released at different intervals was estimated using high-performance liquid chromatography (HPLC) with photodiode array (PDA) detector.

Results:

There was a marginal increase in drug entrapment efficiency with increased drug exposure time but neither the drug entrapment nor the drug release was found to be statistically significant (P ≥ 0.5). Voriconazole was detectable even at 5 weeks.

Conclusion:

A sustained release of voriconazole was achieved up to 5 weeks, when voriconazole was incubated with amniotic membrane for all the studied drug soaking times. Thus, voriconazole impregnated amniotic membrane can be considered for the sustained delivery for its in fungal keratitis.