Cases Of Microbial Keratitis Research Articles

Microbiology Profiles and Antibiotic Susceptibility in Pediatric Microbial Keratitis.

The purpose of this study was to assess trends in microbiology profiles and antibiotic susceptibility among pediatric infectious keratitis cases in Southern California, United States. This is a retrospective chart review of patients aged 18 years or younger diagnosed with infectious keratitis with a positive microbiology culture between 2006 and 2019 at a tertiary academic institution. Patient demographics, microbiology results, and antibiotic susceptibilities were analyzed. There were 23 patients included in the study period. The mean age (±SD) was 11 ± 7 years, with 60% 10 years and older. 75% were female, and 45% were of Hispanic or Latino descent. A total of 14 patients (61%) presented between June and November. A total of 30 microorganisms were identified from 24 corneal cultures of 23 eyes, and 92% were bacterial. The most common gram-positive and gram-negative isolates were Staphylococcus spp. (5/13, 38%) and Pseudomonas spp. (9/15, 60%), respectively. 92.3% gram-positive isolates were susceptible to vancomycin, but only 7.7% were susceptible to erythromycin. Gram-negative isolates were susceptible to gentamicin (86%), ciprofloxacin (79%), and ceftazidime (55%). Pseudomonas spp. was highly susceptible to gentamicin (100%) and ciprofloxacin (83%), and it was moderately susceptible to tobramycin (44%) and ceftazidime (67%). Pediatric microbial keratitis cases in Southern California were predominantly bacterial infections, with gram-positive isolates highly susceptible to vancomycin and gram-negative isolates, particularly Pseudomonas spp., showing high susceptibility to gentamicin and ciprofloxacin.

Incidence of microbial keratitis associated with overnight orthokeratology: a multicenter collaborative study.

To investigate the incidence of microbial keratitis among Japanese patients wearing orthokeratology (ortho-k) lenses STUDY DESIGN: Retrospective multicenter study METHOD: This study was conducted at 4 hospitals in Japan and involved 1438 patients who had been prescribed ortho-k lenses and had worn them for at least 3 months. Data on patient demographics, lens characteristics, lens care systems, and presence of microbial keratitis were extracted from the medical records. Duration of ortho-k lens wear was calculated from the original fitting date to the patient's last visit, with the total years of lens wear used as person-years of lens wear. The incidence of microbial keratitis was calculated by dividing the number of infected cases by the total person-years of lens wear for all enrolled participants. Among the 1438 patients, 753 were male and 685 were female, with a mean age of 12.7 ± 5.4 years. The mean duration of ortho-k lens wear was 5.2 ± 4.5 years, and the mean lens power was -3.52 ± 1.41 D. The total person-years of lens wear for all enrolled patients was 7415. Four cases of microbial keratitis were identified, resulting in an overall incidence of microbial keratitis of 5.4 (95% CI: 1.0-9.8) per 10,000 patient-years among ortho-k lens wearers. This study represents the largest sample size to date for estimating the incidence of microbial keratitis associated with ortho-k lenses. The incidence was similar to or slightly lower than that of previous studies on ortho-k-related microbial keratitis and also comparable to that of daily wear soft contact lenses.

Microbial keratitis in north-western Spain: a review of risk factors, microbiological profile and resistance patterns.

To review the risk factors, clinical characteristics, and microbiological profiles of microbial keratitis cases, as well as the antibiotic resistance patterns of bacterial isolates in the region of Galicia, Spain. This retrospective case series includes patients with culture-positive non-viral microbial keratitis between 2010 and 2020, treated at nine hospitals within the region of Galicia, North-West Spain. The standard protocol involved Gram staining for bacterial infections and calcofluor white staining for fungal or amoebal infections, identification by MALDI-TOF mass spectrometry or microscopy, and antimicrobial susceptibility interpreted according to EUCAST or CLSI guidelines. 780 microorganisms were isolated from corneal scraping cultures from 654 patients. 36.9% resided in urban areas, and 63.1% in rural areas. Isolates were more frequently collected in spring and summer. The median time to corneal scraping was 0 days (IQR 0-2), and the median time to epithelialisation was 24.0 days (IQR 11-49). Most cases had a single corneal infiltrate (509 cases; 77.8%) and affected the stroma (432; 66.1%), with small (< 3mm) epithelial defects (347; 53.1%). Significant risk factors included contact lens wear (24.2%) and exposure to organic matter (4.9%). The most frequent bacteria was CoNS (207; 26.4). Fungi (77; 9.9%) and amoebae (6; 0.8%) were less common. Steroid use and eyelid disease increased resistance in CoNS species. An increase in the percentage of MRSA (compared to MSSA) was detected over the study period (p = 0.045). In Galicia (Spain), microbial keratitis was mostly attributed to CoNS. An increase in MRSA keratitis was observed. Analysis of risk factors may help in suspecting antibiotic resistance. Surveillance programs for detecting the development of antimicrobial resistance are necessary to provide treatment guidelines based on local data.

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.

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.

Risk Factors for Bacterial Keratitis and Severe Disease in Hydrogel Contact Lens Users: A Multicenter Case-Control Study and Case-Only Analysis.

To assess risk factors for contact lens (CL)-related bacterial keratitis, cases and high-risk controls were enrolled. Using high-risk controls can help elucidate whether certain CL types or modalities are attributable to disease burden if risky wear patterns are similar between the cases and controls. This analysis identified whether such CL factors were associated with the occurrence of bacterial keratitis. In addition, a case-only analysis determined CL factors associated with severe disease. From 2018 to 2021, 158 controls were enrolled at University Hospitals of Cleveland Eye Institute, and 153 bacterial keratitis cases were enrolled across 14 sites in the United States. Cases were soft CL wearers with either culture-proven bacterial keratitis or a corneal infiltrate with an overlying epithelial defect within the central 4 mm of the cornea, uveitis, or significant pain. Fungal, protozoan, or nonsoft CL wear-related microbial keratitis cases were excluded. Controls were recruited from high-risk CL wearers with no history of disease. All participants completed a questionnaire related to demographics, type of CL used, wearing schedule, lens handling practices, and storage case handling. Cases with ulcer/infiltrate size ≥2 mm in size, presence of hypopyon, or had fortified antibiotics prescribed were classified as severe keratitis. Univariate and multivariable logistic regression was used to assess association of CL variables with the occurrence of bacterial keratitis as well as occurrence of severe disease among the cases only. Compared with the control cohort, cases were older (mean age 45.6 vs. 38.9 years), had more males (42.5% vs. 23.6%), and had more current or former smokers (41.7% vs. 12.9%). There were no significant associations between CL material (silicone hydrogel vs. not) or CL type (daily disposable vs. reusable) and occurrence of bacterial keratitis. More than two-thirds (67.3%) of cases were classified as severe. Among cases only, univariate analyses found current smokers to have increased risk of severe disease (OR=2.87; 95% CI 1.13-7.26, P =0.03). Adjusting for age, sex, and smoking among the cases only, daily disposable lenses were protective against severe disease (OR=0.32; 95% CI 0.11-0.89, P =0.03). Reusable lenses increased risk of severe microbial keratitis between 3.0- and 4.4-fold compared with compliant daily disposability. Compared with a high-risk control cohort, no specific lens factors were associated with occurrence of CL-associated bacterial keratitis. Among cases only, current smokers and patients wearing reusable lenses are at increased risk of severe keratitis. Daily disposable lenses were protective even when noncompliance to daily disposability was considered.

Comparison of susceptibility of Pseudomonas aeruginosa isolated from keratitis to antibiotics and multipurpose disinfecting solutions

PurposeThis study aimed to assess the susceptibility of ocular isolates of Pseudomonas aeruginosa to two multi-purpose disinfectant solutions (MPDS) and to determine if there was a relationship with resistance to antibiotics. MethodsTwenty-three strains of P. aeruginosa isolated from microbial keratitis cases in Australia were utilized in this study. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of two commercially available MPDSs, Biotrue and cleadew MPS were determined. Additionally, the MIC of the strains to five antibiotics, ciprofloxacin, levofloxacin, gentamicin, ceftazidime, and imipenem, were analyzed. ResultsAll strains were susceptible to 100 % of each of the MPDS. However, when MPDSs were diluted, cleadew MPS had significantly lower median MIC (median = 12.5 vs 25; p = 0.00008) and MBC (median = 25 vs 50; p = 0.0027) compared to Biotrue. All tested strains were susceptible to levofloxacin and gentamicin. Susceptibility rates to ciprofloxacin, imipenem, and ceftazidime were 52.2 %, 30.4 %, and 91.3 %, respectively. There were no significant relations between MIC or MBC to either MPDS and resistance to the antibiotics (p≧0.23). ConclusionBoth MPDSs were active against P. aeruginosa isolated from microbial keratitis in Australia. However, after dilution, cleadew MPS remained active against P. aeruginosa at lower concentrations. Certain strains of P. aeruginosa were resistant to imipenem, ceftazidime or ciprofloxacin. The lack of association of susceptibility to MPDS and antibiotics suggest that resistance to one did not predispose to resistance to the other.

Differentiation of acanthamoeba keratitis from other non-acanthamoeba keratitis: Risk factors and clinical features.

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

Factors Associated With Laboratory Test Negativity Following a Transition in Specimen Collection in Microbial Keratitis Cases

Purpose Negative laboratory results make targeting microbial keratitis treatment difficult. We investigated factors associated with laboratory negativity in patients with microbial keratitis in the context of a transition to a new specimen collection method. Methods Microbial keratitis patients with associated laboratory tests were identified in the electronic health record of a tertiary care facility from August 2012 to April 2022. Patient demographics and laboratory results were obtained. Random sampling of 50% of charts was performed to assess the impact of the ocular history and pretreatment measures. The relationship between probability of negative laboratory results with demographics, ocular history, pretreatment measures, and utilization of a new specimen collection method (i.e. ESwab) was evaluated by multivariable logistic regression. Results Of 3395 microbial keratitis patients identified, 31% (n = 1051) had laboratory tests. Laboratory testing increased over time (slope = 2.5% per year, p < 0.001; 19.6% in 2013 to 42.2% in 2021). Laboratory negative rate increased over time (slope = 2.2% per year, p = 0.022; 48.5% in 2013 to 62.3% in 2021). Almost one-third of patients (31.2%, n = 164) were pretreated with steroids. Over two-thirds of patients were pretreated with antibiotics (69.5%, n = 367). 56.5% (n = 297) of patients were outside referrals. In multivariable regression, patients with corticosteroid pretreatment had lower odds of negative laboratory results (odds ratio [OR] = 0.49, p = 0.001). There were higher odds of negative laboratory results for every additional antibiotic prescribed to a patient prior to presentation (OR = 1.30, p = 0.006) and for specimens collected using ESwabs (OR = 1.69, p = 0.005). Age, prior eye trauma, outside referrals, and contact lens wear were not significantly associated with negative laboratory results. Conclusion More microbial keratitis associated laboratory tests are being taken over time. Over 60% of tests were negative by 2022. Factors associated with negative laboratory test results included pretreatment with antibiotics and specimens collected with the new collection method.

Corneal Culture and Antibiotic Susceptibility Results for Microbial Keratitis in the Mid-Atlantic Region of the United States, 2016 to 2020.

To examine the microbial distribution and antimicrobial susceptibility of culture-positive microbial keratitis at a large tertiary referral center in the mid-Atlantic region of the United States. Retrospective review of culture-positive microbial keratitis cases at the Wilmer Eye Institute from 2016 through 2020. Of the 474 culture-positive microbial keratitis cases, most were bacterial (N=450, 94.9%), followed by fungal (N=48, 10.1%) and Acanthamoeba keratitis (N=15, 3.1%). Of the 450 bacterial isolates, 284 (69.5%) were gram-positive organisms, whereas 157 (28.4%) were gram-negative organisms. The most common bacterial species isolated was coagulase-negative Staphylococcus spp (N=154, 24.8%), and the most common gram-negative isolate was Pseudomonas aeruginosa (N=76, 12.3%). Among fungi, the most common isolates were Candida (N=25, 45.4%), whereas Fusarium (N=6, 10.9%) and Aspergillus (N=3, 5.5%) were less common. Of the 217 bacterial isolates tested for erythromycin susceptibility, 121 (55.7%; ∼60% of coagulase-negative staphylococci and corynebacteria tested) showed resistance to erythromycin. Microbial keratitis in the Baltimore Mid-Atlantic region of the United States is most commonly caused by bacteria, with fungi and acanthamoeba being less common. Gram-positive bacterial infections predominate. Among fungal keratitis cases, Candida species are more commonly encountered than are filamentous species. Use of erythromycin as infection prophylaxis should be reexamined. Findings from our study may guide empiric treatment in this geographic region.

FUNGAL KERATITIS - AN UPDATE ON THE GLOBAL THREAT

Fungal keratitis (FK) is a sight-threatening disease caused by infection of the cornea by filamentous fungi or yeasts. FK can be challenging to diagnose and treat. In tropical, low, and middle-income countries, it accounts for the majority of cases of microbial keratitis (MK). Filamentous fungi, in particular, Fusarium spp., the aspergilli, and dematiaceous fungi are responsible for the most significant burden of disease. The predominant risk factor for filamentous fungal keratitis is trauma, typically with organic, plant-based material. In 2020, the incidence of FK was estimated to be over 1 million cases per year, with a significant geographical variation. Diagnosing FK is challenging accurate diagnosis relies on reliable microscopy and culture. Current topical antifungals are not very effective infections can progress despite prompt treatment. Antifungal drops are often unavailable. When available, natamycin is usually the first-line treatment. However, infections may progress to perforation in ~25% of cases. Future work needs to be directed at addressing these challenges and unmet needs. This review discusses the epidemiology, clinical features, diagnosis, management, and etiology of FK.

Incidence of Corneal Adverse Events in Children Wearing Soft Contact Lenses.

There is increasing interest in fitting children with soft contact lenses, in part due to the increase in prescribing of designs to slow the progression of myopia. This literature review summarizes large prospective and retrospective studies that include data on the incidence of microbial keratitis and corneal infiltrative events (CIEs) in children wearing soft contact lenses. Peer-reviewed prospective and retrospective studies that report contact lens-related complications in children with at least one year of wear and at least 100 patient years of wear were identified. Seven prospective studies published between 2004 and 2022 were identified representing 3,752 patient years of wear in 1,756 children, nearly all of whom were fitted at age 12 years or younger. Collectively, they report one case of microbial keratitis and 53 CIEs, of which 16 were classified as symptomatic. The overall incidence of microbial keratitis was 2.7 per 10,000 patient years (95% CI: 0.5-15), and the incidence of symptomatic CIEs was 42 per 10,000 patient years (95% CI: 26-69). Two retrospective studies were identified representing 2,545 patient years of wear in 1,025 children, fitted at age 12 years or younger. One study reports two cases of microbial keratitis giving an incidence of 9.4 per 10,000 patient years (95% CI: 0.5-15). Accurate classification of CIEs is challenging, particularly in retrospective studies. The incidence of microbial keratitis in children wearing soft lenses is no higher than in adults, and the incidence of CIEs seems to be markedly lower.

Epidemiology and Economic Cost Analysis of Microbial Keratitis from a Tertiary Referral Hospital in Australia.

Microbial keratitis is the most common cause of infective vision loss. The causative organism varies by region, and most cases require intensive antimicrobial therapy. The purpose of this study was to analyse the causative organisms of microbial keratitis, its presentation and economic burden from a tertiary referral hospital in Australia. A retrospective review of 160 cases of microbial keratitis was performed, over a 5-year period from 2015-2020. A wide variety of costs were considered to determine the economic burden, using standardized data from the Independent Hospital Pricing Authority and the cost of personal income loss. Our study showed the most commonly occurring pathogens were Herpes Simplex (16%), Staphylococcus aureus (15.1%) and Pseudomonas aeruginosa (14.3%). A total of 59.3% of patients were admitted, with a median length of admission of 7 days. Median cost for all presentations of microbial keratitis was AUD 8013 (USD 5447), with costs significantly increasing with admission. The total annual cost of microbial keratitis within Australia is estimated to be AUD 13.58 million (USD 9.23 million). Our findings demonstrate that microbial keratitis represents a significant economic burden for eye-related diseases and the key driving factor for the cost is the length of admission. Minimizing the duration of admission, or opting for outpatient management where appropriate, would significantly reduce the cost of treatment for microbial keratitis.

Citrobacter keratitis: predisposing factors and clinical characteristics

PurposeTo report predisposing factors, clinical presentation, antibiotic sensitivity, and management of Citrobacter-caused infectious keratitis.MethodsWe retrospectively reviewed the medical records of culture-proven cases of Citrobacter keratitis in a tertiary referral center for 8 years (from January 2012 to September 2020). Demographic data of the patients, predisposing factors, and presenting signs were extracted.ResultsEighteen cases of microbial keratitis due to Citrobacter spp. were identified. The median age of the patients was 66 years (range: 10–89, interquartile range : 59–81). Thirteen patients were male and 5 were female. Multiple predisposing factors were identified in all eyes, including ocular surface disease (n = 8), previous corneal surgery (n = 6), and history of ocular trauma (n = 6). Five patients were diabetic. Corrected distance visual acuity (CDVA) of patients was light perception (LP) in 8 patients, hand motion (HM) in 7, counting fingers (CF) at 1 m in 1, and CF at 2 m in 2 patients. Thirteen eyes exhibited hypopyon. An area of corneal thinning was observed in 7 eyes (38.9%). Endophthalmitis due to infectious keratitis developed in one patient. In vitro susceptibility testing confirmed high sensitivity to ceftazidime and aminoglycosides. Medical management consisted primarily of topical amikacin (20 mg/ml) combined with topical cefazoline (50 mg/ml) (72.2%). Surgical tectonic procedures were carried out in 7 eyes (38.9%).ConclusionCitrobacter spp. is a rare cause of bacterial keratitis.Previous keratoplasty and ocular surface problems are important risk factors. The prognosis is not good and surgical tectonic intervention is required in many cases to resolve the corneal infection.

Advantages and pitfalls of confocal microscopy for detection of AK

AbstractCorneal infection by the diverse genotypes of the acanthamoeba parasite is becoming an increasingly common aetiology of serious cases of microbial keratitis in Europe, due in part to the growing use of contact lenses. The detection and diagnosis of acanthamoeba keratitis (AK), however, remains challenging in a clinical setting. Several diagnostic methods are typically used, including culture, clinical signs and symptoms, RTPCR, and in vivo confocal microscopy (IVCM). Only IVCM, however, is able to give a rapid and objective result that is not dependent on the location of a limited biopsy sample. Nevertheless, IVCM has both advantages and limitations for AK assessment when applied in a real‐world setting. An overview is given of the current knowledge on distinguishing features of AK when assessed by IVCM, and several challenging cases of suspected AK will be presented, along with considerations regarding how to assess characteristic features seen in IVCM images, that can either be indicative of AK infection, or conversely be features masquerading as AK‐specific findings. Finally, recommendations for the use of IVCM in the clinic for AK assessment, diagnosis and follow‐up will be given.

Accompanying a semi-nested PCR assay to support histopathology findings of fungal keratitis in formalin-fixed paraffin-embedded corneal samples.

Fungal species are responsible for 40%-50% of all microbial keratitis cases. Due to the low amount of extracted DNA in ocular Formalin-fixed Paraffin-embedded (FFPE) samples, selecting a reliable molecular method is a substantial issue in this field. Sixty-six samples were collected via the penetrating keratoplasty (PK) technique. Histopathology assays were performed using hematoxylin-eosin (H&E) and periodic acid Schiff (PAS) staining methods. The ITS1/ITS4 and ITS1/ITS2 primer pairs were used in a semi-nested polymerase chain reaction (PCR) to target the universal internal transcribed spacer (ITS) region. Some PCR results were validated through sequencing. Fungal DNA was detected in 44 of 66 samples (66.7%), and histopathology was positive for 41 of 66 samples (62.1%). Of 41 histopathologically proven fungal-positive cases, 39 were PCR-positive (95%). Moreover, of 44 PCR-positive samples, 39 (88.6%) were histopathology-positive, and 5 (11.3%) were histopathology-negative. Totally in 39 cases (59%), both histopathology and PCR yielded positive results. The Kappa agreement rate between the two diagnostic methods, including histopathology and PCR, was 0.77. Sensitivity, specificity, positive predictive value, and false predictive value were reported as 88.64%, 90.9%, 95.12%, and 80%, respectively. As we reached the acceptable Kappa agreement rate, we concluded that applying the semi-nested PCR assay is a promising method for supporting the evidence by histopathology. Finally, we suggest targeting more specific gene regions using primer pairs that amplify smaller amplicon sizes and surveying novel molecular methods such as NGS to achieve higher sensitivity and Kappa agreement rates.

S1.5a Epidemiology of myotic keratitis in developing countries

S1.5 Mycotic keratitis, September 21, 2022, 11:00 AM - 12:30 PM Mycotic keratitis (corneal infection due to a fungal etiology) is a well-recognized ophthalmological emergency warranting rapid initiation of specific antifungal therapy. However, the magnitude of the problem of mycotic keratitis in the community, especially in the Indian subcontinent and the developing world, is, perhaps, less apparent. A minimal annual incidence estimate of 1051, 787 cases (23.6/100 000 population [popln]) globally has recently been reported, with the highest rates being in Asia (33.9/100 000 popln, an absolute number of 939 895) and Africa (13.5/100 000; 75 196); if all culture-negative cases are assumed to be fungal, especially where the incidence of mycotic keratitis is known to be high, then the annual incidence would be about 1480 916 cases. A fungal etiology has been found to account for a very high proportion (> 45%) of microbial keratitis cases in countries in the Indian subcontinent. Countries where a fungal etiology accounts for >25% of microbial keratitis mostly tend to abut the equator. Interestingly, the proportion of microbial keratitis patients with a proven fungal etiology shows a significant negative correlation with the gross domestic product per capita. Although it is clear that the most common fungal species are Fusarium, Aspergillus, and Candida species, marked regional variations in fungal etiology have been noted. It is important to realize that sensitivity of the culture of ocular fungal pathogens can vary, depending on the pathogen, as well as the competence of the testing laboratory. For some countries, multiple reports over time have been noted, with there being some evidence of an increasing trend in the proportion of all microbial keratitis cases being diagnosed as mycotic keratitis. Even in a single geographical location, cases of mycotic keratitis may be higher than the yearly average at certain times of the year, such as during the harvest or windy seasons, or when there is increased relative humidity. A disturbing statistic to note is that, in 8%-11% of patients with mycotic keratitis, the affected eye needs to be removed, representing an irreversible annual loss of 84 143-115 697 eyes. It is recognized that many people suffering from mycotic keratitis in rural distant communities never present to health care workers due to financial and other constraints. Hence, the actual number of people afflicted by mycotic keratitis, man-days lost due to the disease and during therapy, and reduced quality of life due to persistent disability (corneal scarring) in the Indian subcontinent and developing countries requires further study.

A rare case of Curtobacterium flaccumfaciens infection in the eye: a case report

PurposeTo report a rare case of microbial keratitis caused by Curtobacterium flaccumfaciens (C. flaccumfaciens) infection.Methods and resultsA 24-year-old male presented with pain and redness of the eye following ocular exposure to banana bell sap. He was diagnosed with infectious keratitis and underwent corneal scraping. Subsequent culture and molecular analysis identified the causative organism as C. flaccumfaciens. Keratitis clinically resolved following several weeks of topical therapy with ciprofloxacin 0.3%.ConclusionCurtobacterium flaccumfaciens is a rare and likely underdiagnosed cause of bacterial keratitis. This report provides further evidence of its pathogenic role in not only plants, but also the human cornea, especially in the tropics.

Pain and Acute Vision Loss Secondary to Microbial Keratitis: A Contact Lens-Related Complication

Approximately 45 million individuals in the United States wear contact lenses to correct refractive error, maintain ocular health, or for cosmetic reasons (1). There has been an increasing trend in the number of contact lens users and microbial corneal infections (keratitis). Contact lens wear represents 30% to 50% of all microbial keratitis cases, costing the U.S. health care system $175 million annually (2,3). Corneal infections are an ophthalmic emergency as they can either cause ulceration and perforation of the cornea or disseminate to the intraocular tissues, leading to irreversible blindness.

Clinical and Microbiological Spectra and Therapeutic Outcomes of Polymicrobial Keratitis.

The aim of this study was to evaluate the risk factors, microbiology, and treatment outcomes of polymicrobial keratitis (PMK). We retrospectively analyzed 65 patients diagnosed with PMK between 2016 and 2019. The clinical and microbiological characteristics and outcomes were evaluated. The primary outcome measure was clinical resolution of keratitis. Absolute success (group A) was defined as resolution of infection with medical treatment, qualified success (group B) was resolution with medical therapy and additional minor procedures, and failure (group C) was defined as worsening of infection and presence of corneal melting or perforation requiring therapeutic penetrating keratoplasty or evisceration. Of 4764 cases of microbial keratitis, PMK was identified in 65 eyes of 65 patients (1.36%). Infiltrate was central in 60% (39 eyes). Predisposing factors were higher in group C and included uncontrolled diabetes mellitus in 25% (7/28), history of trauma/foreign body in 57.1% (16/28), and poor presenting visual acuity (0.9 for group A vs. 1.79 for group B vs. 3.00 logarithm of the minimum angle of resolution for group C; P = 0.02). Microbiological profiling revealed that a majority (95%: 62/65) had bacterial with fungal keratitis. High fluoroquinolone resistance was noted (57%; 34/59). Absolute success was achieved in 28.3% (17/60), qualified success in 16.6% (10/60), and treatment failure was noted in 55% (33/60). The final best corrected visual acuity in group A was significantly better than that in group B and C (0.44 vs. 3.00 vs. 2.78; P < 0.001). PMK is extremely rare but responds poorly to medical therapy. Bacterial with fungal etiology is predominant. Early surgical intervention to improve overall outcome is advocated.