Infectious Keratitis Research Articles

Incidence and Outcomes of Infectious Keratitis After Corneal Collagen Cross-Linking Over 10 years From a Tertiary Care Center in South India.

The purpose of this study was to report the incidence and outcomes of infectious keratitis after corneal collagen cross-linking (CXL) over 10 years in South India. Patients who underwent CXL for progressive keratoconus between January 2011 and December 2020 and those with infectious keratitis were identified from an electronic database system. The clinical and microbiological profiles of those affected were extracted from the case files and included in the analysis, whereas viral keratitis was excluded. Eleven eyes with post-CXL infectious keratitis were identified, with 3842 CXL procedures (0.21%) occurring in-house, while 3 were referred from outside. The mean age of the patients was 21.8 ± 7.8 years, and 7 (64%) were male. Six eyes (54%) had conventional isotonic CXL, whereas 5 had hypotonic CXL when pachymetry was <400 μm. Six eyes (54%) presented with hypopyon at a median of 3 days after CXL. Culture of the corneal scrapings grew methicillin-sensitive Staphylococcus aureus in 4 patients, methicillin-sensitive Staphylococcus epidermidis in 2, Aspergillus fumigatus in 1, Aspergillus flavus in 1, Haemophilus parainfluenzae in 1, and no organisms in 2 patients. Almost all the isolates were resistant to ciprofloxacin and other fluoroquinolones. The majority of eyes responded well to intensive topical antibiotics guided by antibiograms and regained 6/18 vision (median). Therapeutic keratoplasty was needed in 2 eyes while cyanoacrylate glue was needed in another 2 eyes. Post-CXL infections are rare, most frequently caused by antibiotic-resistant commensals, and resemble the clinical spectrum and outcomes of non-CXL-related infectious keratitis in most cases.

Clinical Outcomes of Infectious Keratitis Associated with Contact Lens Wear Following Penetrating Keratoplasty: A Case Series.

To report on the clinical characteristics, and outcomes of patients who developed infectious keratitis associated with contact lens (CL) wear following penetrating keratoplasty (PK). A retrospective chart review was performed to identify all patients who underwent PK between November 2012 and January 2023 at a single tertiary referral practice, and subsequently developed CL related infectious keratitis. 74 patients using CL following PK were identified. Charts were reviewed to obtain data about demographics, ocular history, CL usage, microbial culture reports, visual acuity, treatment, and clinical outcomes. CL-associated infectious keratitis occurred in 9 patients, more frequently in males (66%), and patients had a mean age of 54.5 ± 11.8years old. The identified causative organisms included: Stenotrophomonas maltophilia (N = 3), Candida parapsilosis (N = 2), Moraxella nonliquefaciens (N = 1), Pseudomonas aeruginosa (N = 1), Staphylococcus epidermidis (N = 1), Streptococcus mitis (N = 1), Candida albicans (N = 1), and Acanthamoeba (N = 1). Contact lenses were used following PK for an average of 9.1 ± 10.8months before development of keratitis. Patients were followed for 31.8 ± 30.2months after infection. The mean best corrected visual acuity without CL prior to infection was 20/150 and decreased to 20/260 post-infection. Complications following the contact-lens-associated infectious keratitis included: central corneal haze (N = 8), chronic corneal epithelial defects (N = 3), perforation (N = 3), endophthalmitis (N = 1), and enucleation (N = 1). Three grafts required repeat PK. CL-associated infectious keratitis following PK have high rates of complication. Patients should be monitored closely for signs of infection.

Diagnostic performance of deep learning for infectious keratitis: a systematic review and meta-analysis

Infectious keratitis (IK) is the leading cause of corneal blindness globally. Deep learning (DL) is an emerging tool for medical diagnosis, though its value in IK is unclear. We aimed to assess the diagnostic accuracy of DL for IK and its comparative accuracy with ophthalmologists. In this systematic review and meta-analysis, we searched EMBASE, MEDLINE, and clinical registries for studies related to DL for IK published between 1974 and July 16, 2024. We performed meta-analyses using bivariate models to estimate summary sensitivities and specificities. This systematic review was registered with PROSPERO (CRD42022348596). Of 963 studies identified, 35 studies (136,401 corneal images from >56,011 patients) were included. Most studies had low risk of bias (68.6%) and low applicability concern (91.4%) in all domains of QUADAS-2, except the index test domain. Against the reference standard of expert consensus and/or microbiological results (seven external validation studies; 10,675 images), the summary estimates (95% CI) for sensitivity and specificity of DL for IK were 86.2% (71.6-93.9) and 96.3% (91.5-98.5). From 28 internal validation studies (16,059 images), summary estimates for sensitivity and specificity were 91.6% (86.8-94.8) and 90.7% (84.8-94.5). Based on seven studies (4007 images), DL and ophthalmologists had comparable summary sensitivity [89.2% (82.2-93.6) versus 82.2% (71.5-89.5); P=0.20] and specificity [(93.2% (85.5-97.0) versus 89.6% (78.8-95.2); P=0.45]. DL models may have good diagnostic accuracy for IK and comparable performance to ophthalmologists. These findings should be interpreted with caution due to the image-based analysis that did not account for potential correlation within individuals, relatively homogeneous population studies, lack of pre-specification of DL thresholds, and limited external validation. Future studies should improve their reporting, data diversity, external validation, transparency, and explainability to increase the reliability and generalisability of DL models for clinical deployment. NIH, Wellcome Trust, MRC, Fight for Sight, BHP, and ESCRS.

Comment on: Depth, size of infiltrate, and the microbe - The trio that prognosticates the outcome of infective keratitis.

Comment on: Depth, size of infiltrate, and the microbe - The trio that prognosticates the outcome of infective keratitis.

Author's Response to comments on "Depth, size of infiltrate, and the microbe - The trio that prognosticates the outcome of infective keratitis".

Author's Response to comments on "Depth, size of infiltrate, and the microbe - The trio that prognosticates the outcome of infective keratitis".

Photoactivated chromophore for keratitis-Corneal cross-linking in dogs and cats: A retrospective study in Italy.

To evaluate the success and failure rate of photoactivated chromophore for keratitis-corneal cross-linking (PACK-CXL) therapy in a single population of dogs and cats. To identify the usefulness of the PACK-CXL based on ulcer depth and establish a cutoff at which this procedure could be recommended. To analyze the influence of the different variables in corneal healing time and to report the presence of secondary endothelial damage and cataract formation. Medical records of dogs and cats with presumptive infectious keratitis which underwent accelerated epithelium-off PACK-CXL between 2016 and 2023 were reviewed and analyzed. Records for 369 animals were included, and the overall success rate for healing was 97% (range 4-74 days and no rescue procedure). The second success (re-epithelialization <30 days and no rescue procedure) rate was 86%, and a total of 40 eyes needed more than 1 month for the corneal repair. Corneal ulcers were classified in three categories based on the depth: 0%-33% (46%), 34%-66% (37.4%), and 67%-100% (16.5%). The cutoff at which PACK-CXL had a higher probability of failure was with ulcer depth >66.5%. Animals who suffered from keratomalacia and hypopyon at presentation, or were treated with topical serum or gentamicin after PACK-CXL showed an increase in epithelial healing time (EHT). Increasing age, brachycephalic conformation, keratomalacia alone, and deeper ulcers were identified as risk factors for the treatment outcome. Secondary endothelial injury or cataract formation was not noted in this study. Accelerated PACK-CXL is a non-invasive, adjunctive treatment to medical therapy, which can be used in presumed infectious keratitis with a high probability of success. However, it is important to take in consideration the patient age, skull conformation, presence of keratomalacia, and the ulcer depth.

First report of uncommon mycobacteria in post LASIK keratitis: Mycobacterium wolinskyi

Laser assisted in situ keratomileusis (LASIK) surgery is the leading and most performed refractive surgery nowadays. A possible complication of LASIK surgery is infectious keratitis which can lead to disastrous corneal damage and result in permanent loss of vision. LASIK procedures have become increasingly accessible, and the demand for refractive surgery has risen among patients, challenging the medical field to improve the prevention of post-operative infections. Nevertheless, a wide range of pathogens have been described as responsible for post-LASIK keratitis. However, non-tuberculous mycobacterial keratitis remains an infrequent occurrence and is poorly described in the literature. To the best of our knowledge, this is the first ever reported case of post-LASIK keratitis caused by Mycobacterium wolinskyi. We describe the clinical and microbial characteristics, leading to its challenging treatment choice.

Outcomes of sclerokeratoplasty in severe ocular surface disease

Sclerocorneal grafts are procedures considered in cases with extensive corneal and scleral tissue destruction. The study aims to describe sclerokeratoplasty outcomes in severely diseased eyes. We performed a retrospective review of clinical records. Demographic characteristics, medical history, surgical indications, aetiology of perforation, visual outcomes, complications associated with the surgical procedure, and ocular integrity at the end of the follow-up were obtained. Wilcoxon-signed rank tests and Mann-Whitney tests were used to compare complications between groups and outcomes at final follow-up. Survival analysis was performed to analyse vision preservation and global integrity and presented in Kaplan-Meier curves. 40 eyes from 40 patients with a mean age of 48.83 ± 18.85 years and a mean follow-up of 21.13 ± 33.92 months were included in the study. Median corrected visual acuity before and after the procedure remained at 2.8 logMAR. Twenty-seven eyes presented complications. The most common complications were a persistent epithelial defect in 11, hypertension in 10, and perforation in 8 eyes. More than half of the eyes (67.5%) presented with either one or more of all complications after corneoscleral graft. No significant differences were found regarding age, gender, or DM history. Concerning perforation, a significant difference was found between infectious and non-infectious only in the presentation of ocular hypertension (p = 0.048). Vision was preserved in 72.5% of the eyes, with a median survival probability of 4.12 years. Preservation of the ocular integrity was achieved in 85% of the eyes, with a median survival probability of 12 years. Sclerokeratoplasty despite being challenging and technically demanding followed by defiant complications, in some situations such as infectious keratitis and autoimmune diseases, is likely a procedure that salvages the eye and preserves vision.

A single-center study on the distribution and shifting trend of infectious keratitis pathogens from 2018 to 2022

Objective: To investigate the pathogen species, composition, and distribution characteristics of infectious keratitis pathogens in Shandong Province and its surrounding areas. Methods: In this cross-sectional study, patients with keratitis who underwent corneal sampling and microbiological culture at the Shandong Eye Hospital from January 1, 2018 to December 31, 2022 were included. Under topical anesthesia, the edge of the lesion was scraped by an experienced physician. The samples were inoculated on blood agar and Sabouraud dextrose agar plates, separately for bacterial and fungal culture and identification. If necessary, the samples were inoculated on a non-nutrient agar medium with Escherichia coli for Acanthamoeba culture. Bacterial isolates were identified using Vitek 2 compact or matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Fungal isolates were identified based on morphological characteristics or sent to a company for sequencing in cases of difficult identification. The epidemiological data of the patients, pathogen species and number (counting as 1 strain if the same strain was isolated from multiple corneal specimens of the same patient), culture positivity rate, and seasonal distribution were recorded. Differences in pathogen positivity rates among different seasons were analyzed using the chi-square test. Results: Among the 4, 024 patients with infectious keratitis during the study period, there were 2 510 males (62.3%) and 1 514 females (37.6%), aged from 46 days to 94 years. Positive microbial culture results were achieved in 2, 363 patients (58.7%), including 906 cases (38.3%) with bacterial positivity, 1 231 cases (52.1%) with fungal positivity, 28 cases (1.2%) with Acanthamoeba positivity, and 198 cases (8.4%) with mixed fungal and bacterial infections. A total of 2 561 strains were isolated, including 1 104 bacterial strains. The most common bacteria were coagulase-negative Staphylococcus spp. (623/1 104, 56.4%), followed by Streptococcus spp. (131/1 104, 11.9%) and Pseudomonas aeruginosa (68/1 104, 6.2%). The most common fungi were Fusarium spp. (634/1 429, 44.4%), followed by Aspergillus spp. (279/1 429, 19.5%) and Alternaria spp. (229/1 429, 16.0%). Bacterial keratitis was more common in summer and autumn, while fungal keratitis was more common in autumn and winter. Conclusions: Among infectious keratitis cases in Shandong Eye Hospital, Fusarium species were predominant fungal pathogens, while coagulase-negative Staphylococcus predominated in bacterial pathogens. Both fungal and bacterial corneal infections showed seasonal variations.

A Study of Clinico-Microbiological Profile and Treatment Outcomes of Infectious Keratitis.

Background Infectious keratitis (IK) is one of the major causes of corneal blindness in developing and developed nations.Numerous infections, including bacterial, fungal, viral, and protozoa, have been linked to IK. Corneal perforations can happen as one of the complications of IK. In this study, we aim to determine the clinical and microbiological profile and to studythe treatment outcomes of IK. Material and methods It is a prospective, observational, and experimental study conducted in a tertiary care hospital and research centerin Western Maharashtra, India, from September 2022 to June 2024. The sample size was 107 patients with IK. All patients were above 15 years of age, and all cases of microbial keratitis were within the inclusion criteria. Patients less than 15 years of age, patients with any other associated corneal pathology, healed cases of infectious keratitis, peripheral ulcerative keratitis, patients not willing to participate in the study, or not giving consent were excluded. Patients were examined thoroughly, and corneal scraping samples were collected and sent for microbiological examination. Appropriate treatment was provided through medical or surgical management, and treatment outcomes were evaluated during frequent follow-up visits. Results In our study, the majority of patients originated from rural areas, with most being over 60 years of age. Diabetes mellitus was seen in 24.3%, and a history of ocular trauma was present in 48.5% of patients. Staphylococcus epidermidis (3.74%) was the most common organism seen on gram staining, followed by Staphylococcus aureus (2.8%). Pseudomonas aeruginosa was the only gram-negative organism seen. The number of patients who had fungal isolates positive on culture was 57%, 12.1% had bacterial, and 30% had no growth of microorganisms. Fusarium species were seen in 39.2% of culture isolates, followed by Aspergillus flavus and Niger in 7.47% each. In 96% of medically managed patients, ulcers healed within two months. All ulcers with severe and moderate depth required therapeutic penetrating keratoplasty. A graft was in place in 95.2% after therapeutic penetrating keratoplasty, while one patient had graft rejection, and in one patient, endophthalmitis was seen. Conclusion Staphylococcus epidermidiswas the most common bacterial agent isolated on gram staining, and Pseudomonas aeruginosa was the only gram-negative bacillus isolated on gram staining. Fungal isolates were the most common isolates observed on culture, seen in more than half of the IK patients in our study. The majority of patientswho underwent medical management had ulcers healed in two months. The majority of the patients who underwent surgical management had fungal isolates positive.We recommend further research to be conducted in a generalized population, including urban settings, to understand the risk factors, microbiological profile, and treatment outcomes for IK.

Characterization of infectious bacterial keratitis in Östergötland County, Sweden: a 10-year retrospective study.

The aim of this study was to characterize bacterial species, aetiology and antibiotic susceptibility connected to bacterial keratitis infections in Östergötland, Sweden. Retrospective cross-sectional study based on electronic health records for the period 2010-2019. Records of patients diagnosed with infectious keratitis were screened for microbiology confirmed infectious bacterial keratitis. Bacterial species and their susceptibility to antibiotics were determined from microbiology test results. One-hundred and ninety patients with lab culture-confirmed infectious bacterial keratitis were included in the analysis. The most frequently found bacterial species were coagulase-negative staphylococci (39%), Staphylococcus aureus (17%) and Cutibacterium acnes (10%). Pseudomonas spp. was the most frequently found Gram-negative bacterial species (7%). Contact lens wear and severely ill/blind eye were the top two aetiologies associated with bacterial keratitis, 22% of the patients with bacterial keratitis were also diagnosed with glaucoma. Most isolates, 157 out of 173, were susceptible to fluoroquinolones, and 145 out of 155 isolates were susceptible to chloramphenicol. Our results revealed a positive rate of bacterial keratitis of 59% for the samples sent to the laboratory. There was a high susceptibility of the bacterial species to the recommended antibiotics. Our results indicate that it is likely that patients are receiving the correct treatment. Future studies are necessary to monitor changes in antibiotic susceptibility.

Clinical Features and Visual Outcome of Infectious Keratitis Associated with Orthokeratology Lens in Korean Pediatric Patients.

To investigate the clinical features and visual outcome of infectious keratitis associated with orthokeratology (Ortho-K) lens in Korean pediatric patients. We retrospectively reviewed medical records of patients diagnosed with Ortho-K lens-related infectious keratitis from June 2005 to April 2020 at a tertiary referral hospital. Patients' demographics, clinical features, microbiological evaluation, and treatment methods were assessed, and factors related to final visual outcomes were analyzed. The study included 26 eyes from 26 patients (19 female and 7 male patients; mean age, 11.9 years), with an average Ortho-K lens wear duration of 33.7 ± 21.2 months. The highest number of cases occurred in summer (11 of 26 cases, 42.3%). Central or paracentral corneal lesions were observed in 25 cases (96.2%), with a mean corneal epithelial defect size of 5.13 mm2. Pseudomonas aeruginosa was the most commonly isolated organism (n = 5), followed by Serratia marcescens (n = 4). All patients responded to medical treatment without needing surgical intervention. 72% of cases achieved favorable visual outcomes (Snellen best-corrected visual acuity [BCVA] >6 / 12), while 8% experienced severe visual impairment (Snellen BCVA ≤6 / 60) due to residual central corneal opacities. Multivariable analysis showed that non-summer seasons (p = 0.043), duration from symptom onset to presentation (p = 0.040), and corneal epithelial defect size (p = 0.002) were significantly associated with final logarithm of the minimum angle of resolution BCVA. Failed autorefraction at presentation due to an Ortho-K-related infectious keratitis lesion was a significant predictor of poor final visual outcome (Snellen BCVA ≤6 / 12; odds ratio, 38.995; p = 0.030). Ortho-K lens-related infectious keratitis can lead to permanent corneal opacities and potentially devastating visual outcomes in children. Delayed time to presentation, large corneal lesions, failure of autorefraction, and non-summer seasons were associated with poorer outcomes. Proper education and early detection would be key to safe use of orthokeratology lenses in pediatric patients.

Role of Anterior Segment Optical Coherence Tomography in Staging and Evaluation of Treatment Response in Infectious Keratitis.

The aim of this study was to evaluate the role of anterior segment optical coherence tomography during follow-up of infectious keratitis and to assess response to treatment. This was a prospective, consecutive, observational clinical series of cases. Twenty-three eyes of 23 patients with clinically proven fungal keratitis were included in the study. The patients received medical treatment according to clinical diagnosis, and follow-up was performed weekly. Slit-lamp examination and photography, and anterior segment optical coherence tomography were performed at initial and follow-up visits until corneal healing occurred. The main outcome measures included infiltrate depth, width, and density; central corneal thickness; minimal corneal thickness; corneal thickness at the site of the lesion; and stromal thickness at the center of the lesion. Twenty-three eyes of 23 patients (17 men and 6 women), mean age 42.5 ± 19 (8-66) years, were clinically diagnosed with fungal keratitis. Localization was central in 14 cases and paracentral/peripheral in 9 cases. Healing time was 6 to 12 weeks. Minimal corneal thickness, corneal thickness at the site of lesion, and stromal thickness at the center of lesion, and also infiltrate width and depth changed significantly from the first visit to the healing stage at the last follow-up (0.009, 0.001, 0.007, 0.001, and <0.001, respectively). In cases of fungal keratitis, anterior segment optical coherence tomography can provide the clinician with a quantitative assessment of a number of corneal parameters that can be used to determine effectiveness of therapy and confirm complete healing of the lesions that cannot be achieved by clinical evaluation.

Fungal Keratitis in Northwestern Spain: Epidemiology, Risk Factors and Outcomes.

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

Decoding microbial keratitis: Epidemiology, clinical spectrum, and treatment outcomes in a tertiary care setting

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

Evolving indications and surgical techniques for corneal transplantation at a tertiary eye care center in southern China

BackgroundThis retrospective study aimed to analyze the evolution of primary indications and surgical techniques for corneal transplantation in Southern China from 2012 to 2021.MethodsThe medical charts of all patients who underwent keratoplasty between January 2012 and December 2021 at Zhongshan Ophthalmic Centre, Sun Yat-Sen University, Guangzhou, Southern China were reviewed. We collected and analyzed the primary indications for corneal transplantation and the surgical methods used in each keratoplasty.ResultsThe total number of corneal transplantations was 7,286 during this decade, increasing from 210 cases in 2012 to 1054 cases in 2021. The primary indications for keratoplasty included acquired nontraumatic corneal diseases (56.2%), congenital corneal abnormalities (16.4%), acquired traumatic corneal diseases (14.0%), and regraft (13.4%). Infectious keratitis was the leading indication among all keratoplasties (18.5%), followed by regraft (13.4%). Over the decade, the proportion of infectious keratitis gradually decreased (P = 0.013), while the proportion of regraft increased (P = 0.019). The predominant surgical technique was penetrating keratoplasty (PKP), accounting for 56.7%. However, the number of deep anterior lamellar keratoplasty (DALK) and endothelial keratoplasty (EK) significantly increased from 2012 to 2021 (P = 0.007 and P = 0.002).ConclusionsThe annual number of corneal transplants significantly increased from 2012 to 2021. In the past decade, infectious keratitis and regraft have become the leading primary indications for corneal transplantation. Although the use of customized lamellar techniques has dramatically increased, PKP remains the predominant surgical technique for keratoplasty.

Five-year analysis of isolated pathogens and antibiotic resistance of ocular infections from two large tertiary comprehensive hospitals in east China.

To analyze the spectrum of isolated pathogens and antibiotic resistance for ocular infections within 5y at two tertiary hospitals in east China. Ocular specimen data were collected from January 2019 to October 2023. The pathogen spectrum and positive culture rate for different infection location, such as keratitis, endophthalmitis, and periocular infections, along with antibiotic resistance were analyzed. We included 2727 specimens, including 827 (30.33%) positive cultures. A total of 871 strains were isolated, 530 (60.85%) bacterial and 341 (39.15%) fungal strains were isolated. Gram-positive cocci (GPC) were the most common ocular pathogens. The most common bacterial isolates were Staphylococcus epidermidis (25.03%), Staphylococcus aureus (7.46%), Streptococcus pneumoniae (4.59%), Corynebacterium macginleyi (3.44%), and Pseudomonas aeruginosa (3.33%). The most common fungal genera were Fusarium spp. (12.74%), Aspergillus spp. (6.54%), and Scedosporium spp. (5.74%). Staphylococcus epidermidis strains showed more than 50% resistance to fluoroquinolones. Streptococcus pneumoniae and Corynebacterium macginleyi showed more than 90% resistance to erythromycin. The percentage of bacteria showing multidrug resistance (MDR) significantly decreased (χ 2=17.44, P=0.002). GPC are the most common ocular pathogens. Corynebacterium macginleyi, as the fourth common bacterium, may currently be the local microbiological feature of east China. Fusarium spp. is the most common fungus. More than 50% of the GPC are resistant to fluoroquinolones, penicillins, and macrolides. However, the proportion of MDR strains has been reduced over time.

Current Formulation Strategies to Design Novel Carriers for Targeted Drug Delivery and Management of Infectious Keratitis: A Comprehensive Review on the Present State of the Art

Objective: Infectious keratitis is a pernicious disease that affects the anterior segment of the eye and is one the leading causes of blindness worldwide. This disease may cause severe visual impairment or permanent vision damage if left untreated. Discussion: No doubt there are many conventional drug delivery systems to treat ocular keratitis, yet it is the fifth leading cause of blindness globally. This is the result of the eye's complex anatomy and barrier system, which restricts the total ocular contact time of the conventional formulations resulting in underdosing. The widely used traditional formulations to treat keratitis, like antibiotic eye drops and ointments, are rendered useless due to less ocular contact time and low therapeutic drug levels at the target ocular site. The main requirement of the present time is to develop novel drug delivery-backed stratagems to overcome the shortcomings of conventional formulations, which will reduce the morbidity associated with infectious keratitis and improve clinical outcomes. It is worth mentioning that there are documented incidents of Herpetic keratitis of the cornea followed by COVID-19 infection and vaccination. Conclusion: This paper is a rigorous review of all the novel drug delivery strategies to combat ocular keratitis. These future drug delivery strategies will pave the way for the present time researcher and formulation chemists to develop multi-dimensional novel formulations that are safe, patient-compliant, and surpass the ocular barriers to maintain therapeutic drug levels in ocular tissues.

Phototherapeutic keratectomy for treatment of infectious keratitis in a patient with PAX6-related aniridia

Phototherapeutic keratectomy for treatment of infectious keratitis in a patient with PAX6-related aniridia

The Systemic Risk Factors for the Development of Infectious Keratitis after Penetrating Keratoplasty: A Population-Based Cohort Study.

Penetrating keratoplasty (PK) is a corneal surgery that is employed to repair the full-thickness corneal lesion. This study aimed to survey the possible systemic risk factors of infectious keratitis after penetrating keratoplasty (PK) via the Taiwan National Health Insurance Research Database (NHIRD). A retrospective case-control study was conducted, and 327 patients who received the PK were enrolled after exclusion. The main outcome was the development of infectious keratitis, and people were divided into those with infectious keratitis and those without the outcome. Cox proportional hazard regression was conducted to produce adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) of specific demographic indexes and systemic diseases on infectious keratitis. There were 68 patients who developed infectious keratitis after the whole follow-up period. The diabetes mellitus (DM) (aHR: 1.440, 95% CI: 1.122-2.874, p = 0.0310) and chronic ischemic heart disease (aHR: 1.534, 95% CI: 1.259-3.464, p = 0.0273) groups demonstrated a significant association with infectious keratitis. The DM group also revealed significant influence on infectious keratitis development in all the subgroups (all p < 0.05). Nevertheless, the effect of chronic ischemic heart disease on infectious keratitis was only significant on those aged older than 60 years (p = 0.0094) and both sexes (both p < 0.05). In conclusion, the presence of DM and chronic ischemic heart disease are associated with infectious keratitis after PK. However, local risk factors for infectious keratitis developed in those receiving PK had not been evaluated.