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.

Case Series: Mixed Infectious Keratitis by Pythium insidiosum and Fungal Species.

SIGNIFICANCE: This case series is the first to illustrate mixed infection from Pythium sp. and fungal species in corneal ulcer. PURPOSE: This case series aimed to alert all toward the possibility of both Pythium sp. and fungal species infection in case of nonresponding corneal ulcer treated with either antifungals or antipythium drugs alone. Increased suspicion of mixed infection in case of nonresponding fungal/ Pythium keratitis may facilitate early and prompt management. CASE REPORTS: Six patients presented with signs of either fungal or Pythium keratitis. They underwent ophthalmological examinations, smear examinations, cultures, and polymerase chain reaction (PCR). Therapeutic penetrating keratoplasty was performed in cases where symptoms worsened after treatment with either antifungal or antipythium drugs. The half corneal button (HCB) was shared for histopathological and microbiological examinations. In the first case, smear examination from corneal scraping (CS) revealed Pythium -like filaments, which were confirmed with PCR; however, Aspergillus nidulans grew in culture. In the second case, iodine-potassium iodide (IKI) staining was positive for Pythium ; however, PCR was positive for both Pythium and fungus, which was further confirmed by DNA sequencing. In the third case, IKI staining and HCB were positive for Pythium ; however, PCR was positive for fungus, which was identified as Candida saitoana with DNA sequencing. In the fourth case, Pythium grew in the CS culture; however, Candida sp. grew in the HCB culture. In the fifth case, Cladosporium sp. grew in culture from CS; however, Pythium insidiosum grew from the anterior chamber exudate after therapeutic penetrating keratoplasty. In the sixth case, smear examination revealed septate fungal filaments, and Cladosporium sp. grew in culture; however, HCB on histopathological examination showed features of Pythium keratitis. CONCLUSIONS: In unresponsive cases of Pythium or fungal keratitis, diagnostic modalities such as IKI and PCR should be implemented as a routine practice, in addition to smears and cultures.

Epithelial barrier dysfunction in ocular allergy.

The epithelial barrier is the first line of defense that forms a protective barrier against pathogens, pollutants, and allergens. Epithelial barrier dysfunction has been recently implicated in the development of allergic diseases such as asthma, atopic dermatitis, food allergy, and rhinitis. However, there is limited knowledge on epithelial barrier dysfunction in ocular allergy (OA). Since the ocular surface is directly exposed to the environment, it is important to understand the role of ocular epithelia and their dysfunction in OA. Impaired epithelial barrier enhances allergen uptake, which lead to activation of immune responses and development of chronic inflammation as seen in allergies. Abnormal expression of tight junction proteins that helps to maintain epithelial integrity has been reported in OA but sufficient data not available in chronic atopic (AKC) and vernal keratoconjunctivitis (VKC), the pathophysiology of which is not just complex, but also the current treatments are not completely effective. This review provides an overview of studies, which indicates the role of barrier dysfunction in OA, and highlights how ocular barrier dysfunction possibly contributes to the disease pathogenesis. The review also explores the potential of ocular epithelial barrier repair strategies as preventive and therapeutic approach.

Comparison of Corneal Tissue Profile of Pseudophakic and Phakic Donors.

PURPOSE: To compare the endothelial quality of corneas obtained from pseudophakic donors with age-matched phakic controls. METHODS: Retrospective analysis of 100 corneas each from pseudophakic and phakic eyes with donor age ≥60 years in both the groups was performed. The endothelial cell density, coefficient of variation, and percentage of hexagonal cells obtained by specular microscopy were compared between the two groups. The cut-off level of endothelial cell density (ECD) taken for optical keratoplasty was 2,000 cells/mm2. RESULTS: The male and female donors constituted 60% (n=120) and 40% (n=80), respectively. The mean age of the donors was 66.9±7.3 years in the phakic group and 69.9±7.7 years in pseudophakic group. The mean ECD in the phakic group was 2757.6±328.5 cells/mm2 and that in the pseudophakic group was 2225.5±471.9 cells/mm2 (P<0.0001). The mean coefficient of variation in the phakic group was 37.1±5.0 and that in the pseudophakic group was 38.6±11.1 (P=0.234). The mean percentage of hexagonality in the phakic group and the pseudophakic group was 52.0±6.4% and 51.2±7.2%, respectively (P=0.414). Both in univariate and multivariate linear regression analysis, age of the donor was found to be negatively associated in predicting ECD (P=0.002 and P=0.003, respectively). Sixty-nine and thirty-three corneas from the phakic and pseudophakic donor pool were used respectively. CONCLUSION: Difference in ECD between the phakic and the pseudophakic donor group was found to be statistically significant. The ECD in the pseudophakic group was found to be above the cut-off limit required for keratoplasty. Hence, pseudophakic corneas may also be used for transplantation.

Outcome of four-point fixated open loop polymethyl methacrylate anterior chamber intraocular lens.

PURPOSE: To study long-term visual and refractive outcomes and complications in eyes with anterior chamber intraocular lens (ACIOL) implantation. METHODS: Data of patients who underwent primary and secondary ACIOL implantation at L V Prasad Eye Institute, Bhubaneswar between 2011 and 2020 was collected, including details of post-operative visits. For analysis, sample was divided into: group Ia (primary ACIOL in cases without risk factors, n = 104); group Ib (primary ACIOL in cases with pre-existing risk factors, n = 49); and group II (secondary ACIOL, n = 40). RESULTS: A total of 193 eyes of 192 patients were included. Mean post-operative follow-up in groups I and II were 8.6 and 11.51 months, respectively. Mean pre-operative and last visit corrected distance visual acuity were 1.73 ± 0.11 and 0.42 ± 0.05 logMAR units in group Ia (p < 0.001), and 1.53 ± 0.14 and 0.49 ± 0.10 logMAR units in group Ib (p < 0.001). The mean spherical equivalent (MSE) for last refraction was -0.37 ± 0.18 diopters (D) and -0.15 ± 0.51 D in groups I and II, respectively. Of 76 eyes in which addition of 2.5 D (over the near emmetropic posterior chamber intraocular lens power) was taken for ACIOL, 40 (52.6%) had MSE within ± 0.5 D. Most common complications were transient corneal edema and anterior chamber reaction. Eyes on anti-glaucoma medications at last visit were eight (7.7%), 15 (30.6%), and two (5.0%) in groups Ia, Ib, and II, respectively. CONCLUSION: We observed that ACIOLs have good visual and refractive outcomes. Raised IOP is a concern in eyes with pseudoexfoliation, but can be managed with close monitoring. Hence ACIOL can be a good option for managing aphakia after cataract surgery.

Comparative profile of ocular surface microbiome in vernal keratoconjunctivitis patients and healthy subjects.

PURPOSE: To compare ocular surface microbiome and its antibiotic sensitivity in vernal keratoconjunctivitis (VKC) with normal ocular surface. METHODS: In this case-control study, thirty patients each with clinical diagnosis of VKC and age-matched controls with normal ocular surface were enrolled. Tear film samples were collected from each group and subjected to microbial evaluation with microscopy, conventional culture methods, and polymerase chain reaction (PCR). Microbial diversity and antibiotic sensitivity patterns were analyzed. RESULTS: Most patients (67%) belonged to severe grades (3 and 4) of VKC, and allergic history could be elicited in 20%. On culture, bacteria were isolated in 50% of VKC patients and 47% of control group. Staphylococcus species were identified in 70% VKC group and 57% control group. S. aureus growth was seen in 52% and 21% of VKC patients and controls, respectively. S. pneumoniae was isolated only in controls (29%) (p<0.05). Confluent colonies (≥10 colonies/µl) were seen in 70% of VKC patients and 14% of controls (p<0.05). Fluoroquinolone resistance was more among higher grades of VKC (50%) (p<0.01) and was observed in 46% of VKC patients and 23% of control group (p<0.01). Both groups were negative for HSV-1 DNA and fungal growth. CONCLUSION: Staphylococcus, the most common ocular surface flora, was predominant in VKC patients. Microbial analysis revealed similar microbial diversity in both groups. However, bacterial load was higher in VKC. Increased fluoroquinolone resistance was observed in VKC patients with more resistance among higher grades. Fungi and HSV-1 were not seen in VKC or normal ocular surface.

Acid and heat fastness in microsporidia: How acid fast are acid fast microsporidium?

Microsporidia are obligate spore-forming microorganisms with strong resemblance to fungi and can affect almost every organ system in immunocompetent or immunocompromised individuals. Mixed infections are also reported in immunocompromised hosts. Microsporidial spores show marked morphological variations and the small and slender forms can resemble bacilli. Modified Zeihl Neelsen (ZN) stain, cold method demonstrates them as bright red in color, leaving several spores blue or incompletely stained; thus, they are reported as weakly or variably acid fast. Variability in staining results with ZN stain and considering the fact that Mycobacterium tuberculosis, the commoner bug in developing countries is identified by its resistance to stronger acids on ZN staining, authors wished to demonstrate acid and heat fastness in microsporidium using corneal tissue specimens. Microsporidial spores stained bright red in color with conventional ZN stain, demonstrated strong acid fastness, and interestingly the staining results improved on heating. Thus, the authors conclude that they are strongly acid and heat fast and care must be warranted so that they are not misdiagnosed as Mycobacterium or other acid-fast organisms. Careful observation of morphology, battery of special stains, and molecular diagnostics should be advocated for diagnostic confirmation. To the best of the authors' knowledge, this is the first explicit report on acid and heat fastness on microsporidial spores.

Colistin resistance in Gram-negative ocular infections: prevalence, clinical outcome and antibiotic susceptibility patterns.

PURPOSE: To study the prevalence, antibiotic susceptibility profile, clinical outcomes and plasmid-mediated transfer of colistin resistance (CLR) among Gram-negative bacilli (GNB) isolates from different ocular infections. DESIGN: Prospective case-control study in eastern India. METHODS: Consecutive ocular samples with GNB isolates from clinically diagnosed cases of microbial keratitis, infectious endophthalmitis and orbital infections were included. Inclusion criteria were significant GNB growth from ocular samples and > 6 weeks follow-up. Clinical outcomes were determined by disease-specific criteria for each clinical group. Antibiotic susceptibility was tested by broth microdilution for colistin and Kirby-Bauer disc diffusion method for others. Plasmid detection for CLR genes mcr-1 and mcr-2 genes was done by standard protocols. RESULTS: Sixty GNB isolates were studied. Overall prevalence of CLR (intrinsic plus acquired) was 40% (n = 24), acquired being 37.5% of CLR isolates (n = 9). The prevalence varied from 45.5% (10/22) and 45% (9/20) in microbial keratitis and infectious endophthalmitis, respectively, to 26.3% (5/19) in orbital infections. Clinical outcomes in CLR patients were significantly worse in microbial keratitis (p = 0.018) and orbital infections (p = 0.018), and comparable to colistin-susceptible ones (p = 0.77) in infectious endophthalmitis. CLR isolates had significantly higher resistance to Amikacin, Gentamicin and Ceftazidime but were susceptible to Piperacillin, Carbapenems and fluoroquinolones. Plasmids mcr-1 and mcr-2 were detected in 6.25% (n = 1) and 25%(n = 4), respectively, of the 16 tested isolates. CONCLUSIONS: CLR is highly prevalent in ocular isolates and affects clinical outcomes. CLR isolates may still remain susceptible to Carbapenems, Piperacillin and fluoroquinolones. Plasmid mcr-1- and mcr-2-mediated CLR remains low in ocular infections.

Mast cells contribute to the induction of ocular mucosal alloimmunity.

Beyond their historical role as the effector cells in allergic disorders, mast cells have been implicated in regulating both innate and adaptive immune responses. Possessing considerable functional plasticity, mast cells are abundant at mucosal surfaces, where the host and external environments interface. The purpose of this study was to evaluate the contribution of mast cells to allograft rejection at the ocular surface. Using a well-characterized murine model of corneal transplantation, we report that mast cells promote allosensitization. Our data show mast cell frequencies and activation are increased following transplantation. We demonstrate that mast cell inhibition (a) limits the infiltration of inflammatory cells and APC maturation at the graft site; (b) reduces allosensitization and the generation of Th1 cells in draining lymphoid tissues; (c) decreases graft infiltration of alloimmune-inflammatory cells; and (d) prolongs allograft survival. Our data demonstrate a novel function of mast cells in promoting allosensitization at the ocular surface.

Mesenchymal Stem Cells Modulate Differentiation of Myeloid Progenitor Cells During Inflammation.

Mesenchymal stem cells (MSCs) possess distinct immunomodulatory properties and have tremendous potential for use in therapeutic applications in various inflammatory diseases. MSCs have been shown to regulate pathogenic functions of mature myeloid inflammatory cells, such as macrophages and neutrophils. Intriguingly, the capacity of MSCs to modulate differentiation of myeloid progenitors (MPs) to mature inflammatory cells remains unknown to date. Here, we report the novel finding that MSCs inhibit the expression of differentiation markers on MPs under inflammatory conditions. We demonstrate that the inhibitory effect of MSCs is dependent on direct cell-cell contact and that this intercellular contact is mediated through interaction of CD200 expressed by MSCs and CD200R1 expressed by MPs. Furthermore, using an injury model of sterile inflammation, we show that MSCs promote MP frequencies and suppress infiltration of inflammatory cells in the inflamed tissue. We also find that downregulation of CD200 in MSCs correlates with abrogation of their immunoregulatory function. Collectively, our study provides unequivocal evidence that MSCs inhibit differentiation of MPs in the inflammatory environment via CD200-CD200R1 interaction. Stem Cells 2017;35:1532-1541.

Fusarium keratitis at a tertiary eye care centre in India.

The aim of the study was to report the clinical and microbiological profiles of Fusarium keratitis. In this single-centre, retrospective, non-comparative case series, 47 laboratory-confirmed cases of keratitis caused by Fusarium species treated at the L V Prasad Eye Institute, Bhubaneswar, India, between November 2006 and October 2009, were reviewed. The analysis included predisposing factors, clinical characteristics, microbiological findings, treatment and outcome. Forty-seven samples of 47 patients were included in the study. The mean age of the 47 patients was 46 ± 17 years. Twelve eyes had a history of injury. Corneal scraping could not be done in one of the cases due to large perforation. Fungal filaments were detected in corneal scraping in 41 cases, and in three cases microconidia were observed in microscopy. Fusarium solani was the most common species (44.7 %). All three cases where microconidia were present in smear were identified as F. solani in culture. The mean time to positive culture was 2.4 ± 1.5 days. Twenty-three patients underwent adjunctive surgical procedure. Visual acuity of <20/200 at presentation and final follow-up was noted in 80.9 and 51.4 % patients, respectively. One-half (23/47) of the patients had improvement in visual acuity. Fusarium keratitis may present after trauma without any satellite lesion, and the response to medical therapy is generally poor. Rapid diagnosis can be made by smear examination of corneal scrapings in a majority of the cases and confirmed by culture within 2-3 days. Presence of microconidia in smear examination may be suggestive of F. solani.

Safety and Efficacy Profile of Corneas Harvested From Donors of Drowning Victims.

PURPOSE: The aim of this study was to analyze the tissue quality and outcomes of corneal transplants from donor corneal tissues harvested from drowning victims. METHODS: This retrospective study was conducted on corneal tissues harvested from drowning victims between March 2018 and September 2022. Details of the tissue quality and outcomes after keratoplasty were collected from the eye bank and outpatient records. RESULTS: Thirty-four donor corneas were collected from drowning victims during the study period. The mean age of the donors was 37.1 ± 20.3 years. The mean donor-to-preservation time was 4.9 ± 2.6 hours. The mean endothelial cell density was 3025 ± 271 cells/mm 2 . Twenty donor corneas (58.8%) were used at our institute, 2 were stored in glycerol for future use, and 12 were transported to other transplant centers. The overall utilization was 94.1% (32/34 corneas). Of the 20 corneas used at our institute, 17 were used for optical grafts and 3 for therapeutic indications. Of the 17 optical grafts, 10 were used for optical penetrating keratoplasty, 6 for endothelial keratoplasty, and 1 for anterior lamellar keratoplasty. The most common indication for keratoplasty was regrafting the previously failed grafts (25%). None of the transplanted eyes developed an infection in the immediate postoperative period. Eight eyes had clear grafts after 3 months. Of the 12 tissues transferred to other keratoplasty centers, 10 were used for optical grafts and 2 for therapeutic/tectonic grafts. CONCLUSIONS: Donor corneas retrieved from drowning victims may be considered safe for transplantation. The postoperative outcomes of the tissues obtained from these donors were satisfactory. Hence, these donor corneas can be optimally used in routine transplantation procedures.

Microkeratome versus manually dissected donor tissue for Descemet stripping endothelial keratoplasty: A randomized prospective study.

PURPOSE: To compare the visual outcomes, postoperative complications, and graft asymmetry between precut and manually dissected donor tissues for Descemet stripping automated endothelial keratoplasty (DSAEK) and Descemet stripping endothelial keratoplasty (DSEK) procedures, respectively. METHODS: Seventy eyes of 70 patients undergoing DSEK/DSAEK at a tertiary eyecare center in eastern India were included in this prospective randomized control study. The 70 eyes were divided equally into two groups. Group A (n = 35) and Group B (n = 35) underwent DSEK and DSAEK procedures, respectively. the operating surgeons prepared the manually dissected corneal grafts using lamellar dissectors. the eye bank technicians prepared the precut corneal grafts using a microkeratome. The patients were investigated postoperatively after 1 day, 1 week, 1 month, 3 months, and 6 months. The data were compared for visual outcomes [uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), spherical and cylindrical refraction, and spherical equivalent], incidence of postoperative complications, and pachymetry. RESULTS: The mean age was 56.5 (±17.8) years, and the male-to-female ratio was 1.3:1. The most common indications were pseudophakic bullous keratopathy (45.71%, 32/70), failed graft (32.86%, 23/70), and Fuchs' endothelial corneal dystrophy (10%, 7/70). The indications for surgery (P = 0.732) and donor (P = 0.258) and host pachymetry (P = 0.986) were comparable between both groups. There was no significant difference in change of UCVA, BCVA, and postoperative refraction (mean spherical refraction, P = 0.849; mean cylindrical refraction, P = 0.516; spherical equivalent, P = 0.518) between the two groups. Postoperative complications like graft detachment (P = 0.179), graft failure (P = 0.513), graft infiltrate (P = 0.428), and endophthalmitis (P = 0.493) were higher in the DSAEK group; however, the difference between the groups was insignificant. The graft asymmetry index was higher in DSAEK than in DSEK; the difference was significant till the 1-month follow-up (P = 0.005). CONCLUSION: The outcome was similar in both groups. Therefore, manual donor dissection can be an alternative for microkeratome-assisted dissection in low-resource centers and countries to achieve good results.

Keratic Precipitates: An Overlooked Sign of Microsporidial Stromal Keratitis?

PURPOSE: To elucidate a distinctive clinical feature in cases of microsporidial stromal keratitis (MSK). METHOD: A retrospective observational study of cases with a histopathological and/or microbiological diagnosis of MSK on corneal biopsy or host corneal button between 2016 and 2022 was conducted. RESULTS: Eighteen cases with a confirmed histopathological and/or microbiological diagnosis of MSK were detected. Careful review of slit-lamp photographs revealed the presence of pigmented keratic precipitates (KPs) beyond the area of stromal keratitis in five out of eighteen cases (27.7%). CONCLUSION: The presence of pigmented KPs beyond the area of lesion can alert the clinician to keep microsporidia as a differential cause for stromal keratitis. Management can be tailored accordingly for a better outcome.

The role of corneal biopsy in the management of microbial keratitis.

PURPOSE: Corneal biopsy helps in diagnosing deep-seated or recalcitrant lesions of microbial keratitis (MK). We aim to analyze its role in managing these challenging cases. METHODS: This is a retrospective review of 22 cases of corneal biopsy at our institute from January 2010 to December 2021. Data were retrospectively collected using the electronic medical record (EMR) system. Those cases of indolent, progressive MK or deep-seated lesions where cornea scraping was not possible were considered for corneal biopsy to establish the microbiological diagnosis. The primary aims of our study were to analyze the indications, success rates, and outcomes for biopsy patients in our series. Additional outcomes that were analyzed included the average time from presentation to biopsy, the type of causative organism isolated from the biopsy by either histopathological or microbiological method, and the frequency and outcome of surgical interventions performed. Descriptive statistics using mean (±standard deviation) and median (±range) were used to interpret the demographic data. RESULTS: Overall, 15 of 22 patients (68%) had a positive corneal biopsy after microbiological or histopathological examinations. The most identified organism was microsporidia (n = 4,30.7%), followed by mycobacteria (n = 2,15.4%), gram-negative bacilli (n = 2,15.4%), acid-fast bacilli (n = 1,7.6%), fungus (n = 2,15.4%), gram-positive cocci (n = 1,7.6%), and mixed bacterial infection (n = 1,7.6%). CONCLUSION: Corneal biopsy should be considered a diagnostic modality for patients with deep-seated or unresponsive MK. It can improve the treatment for MK, ensuring targeted therapy.

Atypical mycobacterial keratitis: Clinical outcome in nonrefractive surgery cases.

PURPOSE: To identify the predisposing factors, clinico-microbiological profiles, and treatment responses in patients with atypical mycobacterial keratitis. METHODS: The study retrospectively analyzed patients who presented at a tertiary eyecare center in eastern India with atypical mycobacterial keratitis between 2008 and 2021. The diagnostic criteria included cases positive for acid-fast bacilli on Ziehl-Nielsen stain or culture. The antibiotic susceptibility pattern was observed, and treatment was initiated accordingly. RESULTS: Out of the 29 cases, ocular predisposing factors were present in 62.1% with an antecedent history of trauma, and vegetative matter was the most common risk factor. There was no predisposing association with systemic conditions in any case. A long lag time was observed between the onset of corneal infection and presentation in 79.3% of cases, with the average time being 43.7 days. Clinical signs mimicked fungal keratitis in most cases. Typical cracked windshield appearance was only observed in two cases. Two patients presented with clinical pictures like peripheral ulcerative keratitis. Topical amikacin was used as treatment in 28 cases. Based on disk diffusion assay, 28 (96.5%) isolates were sensitive to amikacin. Twelve (41.3%) were sensitive to vancomycin, six (20.6%) to gatifloxacin, six (20.6%) to ciprofloxacin, and four (13.7%) to moxifloxacin. Twelve participants showed good final visual acuity posttreatment, which improved to over two lines of Snellen's visual acuity chart (44.5%). CONCLUSION: Atypical mycobacteria keratitis may not present with classically described clinical features. The duration of presentation, clinical presentation, special microbiological stains, targeted therapy, and antibiotic susceptibility patterns are the key to successfully managing these intractable infections and obtaining favorable outcomes.

Ring infiltrate in staphylococcal keratitis.

Smear and culture tests of corneal scrapings from a patient with a ring infiltrate confirmed significant growth of a Staphylococcus species resistant to fluoroquinolones. Because of nonresponse to medical management, the patient underwent therapeutic penetrating keratoplasty. Staphylococcal infection of the cornea may appear as a ring-like infiltrate that is recalcitrant to medical management.

Rho-kinase inhibitors: Role in corneal endothelial disorders.

PURPOSE: This exhaustive review of published literature aims to put forth the current understanding, and experiences of the role Rho-kinase inhibitors play in the management of corneal endothelial disorders. METHODS: A meticulous search for PubMed and Medline databases was carried out using keywords 'rho-kinase inhibitors', 'corneal endothelial disorders', 'rho-kinase inhibitors in corneal endothelial disorders', and 'fuchs endothelial corneal dystrophy'. The articles published in last five years relevant to the area of interest were selected and compiled in a chronological order to write this review. RESULTS: Published research shows the proven role of rho-kinase inhibitors in promoting endothelial proliferation and suppressing its apoptosis. It has shown to be effective in the treatment of endothelial diseases and endothelial cell loss due to other causes in small clinical studies. It has also shown to promote growth of human corneal endothelial cell culture suitable for transplantation. The side effects of topical rho-kinase inhibitors are minimal and self-limiting. CONCLUSION: Rho-kinase inhibitors show immense promise in providing a non-surgical therapy for treatment of endothelial disorders. If consistent results are demonstrated through large clinical trials then this can be a major breakthrough in treating endothelial decompensation and reduce our dependence on endothelial keratoplasty for the same.

Use of Ethylenediaminetetraacetic Acid in Chronic Calcium-Based Chemical Injury.

PURPOSE: This study presents the successful management of a patient with chronic chemical-based injury using ethylenediaminetetraacetic acid (EDTA) chelation. METHODS: This is a case report of a 59-year-old man who presented to us 2 months after a bilateral, accidental, ocular injury with lime particles at his workplace. RESULTS: The patient was initially managed with extensive debridement and amniotic membrane grafting for both eyes. At 4-month follow-up, the left eye appeared to have extensive calcium-based plaques. 0.02N EDTA chelation was performed for his left eye. Postchelation, the visual acuity improved to 20/800. At 1-week follow-up, a repeat EDTA chelation was performed. The corneal clarity improved further, and the patient recovered a visual acuity of 20/200. CONCLUSIONS: EDTA chelation in the setting of calcium deposition in the chronic phase of chemical injuries can be reasonably effective.