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Copyright of Baghdad Science Journal is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The corneal epithelium is a layer in the anterior part of eye that contributes to light refraction onto the retina and to the ocular immune defense. Although an intact corneal epithelium is an excellent barrier against microbial pathogens and injuries, corneal abrasions can lead to devastating eye infections. Among them, Pseudomonas aeruginosa-associated keratitis often results in severe deterioration of the corneal tissue and even blindness. Hence, the discovery of new drugs able not only to eradicate ocular infections, which are often resistant to antibiotics, but also to elicit corneal wound repair is highly demanded. Recently, we demonstrated the potent antipseudomonal activity of two peptides, Esc(1-21) and its diastereomer Esc(1-21)-1c. In this study, by means of a mouse model of P. aeruginosa keratitis and an in vivo corneal debridement wound, we discovered the efficacy of these peptides, particularly Esc(1-21)-1c, to cure keratitis and to promote corneal wound healing. This latter property was also supported by in vitro cell scratch and ELISA assays. Overall, the current study highlights Esc peptides as novel ophthalmic agents for treating corneal infection and injury, being able to display a dual function, antimicrobial and wound healing, rarely identified in a single peptide at the same micromolar concentration range. [ABSTRACT FROM AUTHOR]

The corneal epithelium is a layer in the anterior part of eye that contributes to light refraction onto the retina and to the ocular immune defense. Although an intact corneal epithelium is an excellent barrier against microbial pathogens and injuries, corneal abrasions can lead to devastating eye infections. Among them, Pseudomonas aeruginosa-associated keratitis often results in severe deterioration of the corneal tissue and even blindness. Hence, the discovery of new drugs able not only to eradicate ocular infections, which are often resistant to antibiotics, but also to elicit corneal wound repair is highly demanded. Recently, we demonstrated the potent antipseudomonal activity of two peptides, Esc(1-21) and its diastereomer Esc(1-21)-1c. In this study, by means of a mouse model of P. aeruginosa keratitis and an in vivo corneal debridement wound, we discovered the efficacy of these peptides, particularly Esc(1-21)-1c, to cure keratitis and to promote corneal wound healing. This latter property was also supported by in vitro cell scratch and ELISA assays. Overall, the current study highlights Esc peptides as novel ophthalmic agents for treating corneal infection and injury, being able to display a dual function, antimicrobial and wound healing, rarely identified in a single peptide at the same micromolar concentration range.

Contact lenses are used by approximately 300 million people worldwide, mainly for the correction of refractive errors, representing an effective and aesthetic method. However, noncompliance with related hygiene rules can lead to sight-threatening complication. Understanding how the general population uses contact lenses should be a concern for both the ophthalmologist and the family doctor, as it is an essential step towards reducing the infectious complications by implementing effective preventive measures. Through a cross-sectional study, using a web-based survey, composed of 28 questions aspects, there were evaluated aspects related to the correct use of contact lenses, as well as aspects related to infectious complications that may occur due to defects in their correct wear and care. The target group consisted of contact lens wearers over the age of 18. The participants were interviewed about their compliance with hygiene rules related to contact lens use and a compliance score was calculated. The presence of ocular symptoms specific to corneal infections and corneal infections diagnosed during contact lens use was also analysed. A total of 3604 respondents participated in this study, of which 99.7% reported making at least one contact lens hygiene risk behavior. In addition, the findings of this study revealed a high prevalence of ocular symptoms specific to corneal infection and also of corneal infection among users. [ABSTRACT FROM AUTHOR]

Background: Fungal keratitis accounts for 50% of all microbial keratitis, depending upon the geographic location. Filamentary fungi are predominant in tropical and subtropical climates. Treatment is given based on clinical diagnosis supported by the presence of fungus in potassium hydroxide (KOH) mounting, rather than on culture report because culture takes time. Reported studies from northern part of the country revealed Aspergillus as the most common fungus, whereas Fusarium was reported to be the most common fungus in southern part of the country. Aspergillus fumigatus is the most common fungus isolated in our study and the response to standard treatment is good. Aim of the Study: To identify spectrum of fungi, response to the standard treatment given, and sensitivity of KOH preparation in clinically diagnosed fungal corneal ulcers and to identify the predisposing factors and culture-positive cases (both Sabouraud's and blood culture). Methods: All patients who were clinically diagnosed to have fungal corneal ulcer, based on history, clinical features, and slit-lamp findings over a period of 1 year, were included in the study. All patients were subjected to corneal scraping and the material was examined by KOH mounting, Gram staining, and specific culture techniques. The ulcer was treated as per the standard treatment protocol followed in the institution, and the response to treatment was analyzed. Results: The study included 40 patients, with males being predominated (n = 36). KOH positivity was seen in 34 (85%) cases whereas KOH negativity was seen in 6 (15%) cases. Gram stain was positive in 6 (15%) cases. The culture was positive in all cases (100%). The most common fungus isolated was A. fumigatus – 24 (60%) cases. The response to the treatment after 8 weeks was found in 34 (85%) cases. Enucleation was done in 7 (17.5%) cases. Total therapeutic keratoplasty was done in 7 (17.5%) cases. Total penetrating keratoplasty was done in 4 (10%) cases. Conclusions: Rapid diagnosis and early institution of antifungal therapy are necessary to prevent ocular morbidity and blindness. Although culture helps in definite diagnosis and identification, direct microscopic detection of fungal structures in corneal scrapes permits a rapid presumptive diagnosis.

The article presents a review of the literature on the various possibilities in application of antifungal drugs in the treatment of fungal keratitis. The fungal infection of the eye is one of the problems unsolved in the modern ophthalmology, which often leads not only to blindness, but to the loss of the eye as an organ. Despite decades of experience in the pharmacological treatment of fungal keratitis, the question of the officinal production of ophthalmic antifungal drugs has not yet been resolved. An ophthalmologist who has such patients is forced to search for resources available to him to provide medical care. As can be inferred from the literature, nowadays the drugs of first choice are natamycin, amphotericin B, fluconazole, and voriconazole. However, neither dosing nor modes of administration of these drugs are still standardized. It is also necessary to take into account possible side effects in their local and systemic application. Despite advances in the diagnosis and therapeutic treatment of mycotic keratitis, up to 27% of patients still require surgical interventions. But postoperative recurrences of the infection process can occur. More research (and closer attention from pharmaceutical companies) is needed to further investigate the routes of administration, concentrations and effective combinations of antifungal drugs as well as the improvement of the methods of diagnosing fungal infection.

AIM: To investigate the spectrum and antibiotic susceptibility of bacteria isolated from patients with suspected corneal infections in Zhongshan Ophthalmic Center in South China over the past four years retrospectively. METHODS: Totally 1943 corneal scrapes from patients with corneal infections from 2010 to 2013 were cultured and processed using standard microbiological procedures to identify bacterial isolates. Simultaneously, the bacterial isolates were tested for antibiotic susceptibility to 8 antibiotics (ceftazidime, cefuroxim, cefazolin, levofloxacin, ofloxacin, neomycin, tobramycin, chloramphenicol) using the Kirby-Bauer disc diffusion technique. RESULTS: Of the total 1943 scrapes, 397 (20.43%) were culture-positive, of which 294 (74.06%) were gram-positive (GP) and 103 (25.94%) were gram-negative (GN) bacteria. Of the GP organisms, the most prevalent genera were Staphylococcus spp. (56.17%, n=223), Kocuria spp. (5.29%, n=21) and Micrococcus spp. (1.26%, n=5). On the other hand, the most prevalent genera were Pseudomonas spp. (12.85%, n=51), Burkholderia spp. (2.02%, n=8) and Acinetobacter spp. (1.51%, n=6) for the GN organisms. Among five antibiotics that have eye drop products, the resistant to neomycin of GP (7.82%, 95% CI: 4.72%-10.92%) and GN isolates (9.71%, 95% CI: 4.01%-15.41%) was lowest, while the resistant to chloramphenicol was highest (GP: 34.35%, 95% CI: 28.92%-39.78%; GN: 60.19%, 95% CI: 50.74%-69.64%). CONCLUSION: Staphylococcus spp. was the most common bacterial pathogens isolated from patients with corneal infections in this setting. High percentages of GP and GN bacteria were mostly susceptible to neomycin and highly resistant to chloramphenicol.

Purpose: The aim of the study was to develop a novel formulation of levofloxacin and besifloxacin to achieve improved mucoadhesion and permeability of besifloxacin and levofloxacin through cornea for the effective treatment of ocular infections.Methods: A multicomponent hydrogel formulation containing chitosan-polyvinyl alcohol (PVA)-poly(N-vinylpyrrolidone) (PVP) was designed. Lysophosphatidylcholine was used to enhance corneal penetration of the drugs. The hydrogel preparations were characterized for various parameters, including clarity, pH, viscosity, in vitro release kinetics, mucoadhesion, ex vivo human corneal permeation, and antimicrobial efficacy. The formulations were compared with standard drug solution and marketed eye drops (Besix® and Levotop®).Results: Compared to commercial ophthalmic preparations and free drug solutions, hydrogel formulation of both besifloxacin and levofloxacin was found to have 3.5- and 8-fold higher (P < 0.001) mucoadhesion and superior cumulative corneal permeation. The formulations showed superior in vitro anti-infective properties. Incubation of besifloxacin and levofloxacin formulations with Staphylococcus aureus-infected cornea model for 0.5 h showed greater potency of the hydrogel formulations compared to the marketed eye drops and standard solutions.Conclusions: The results of the study show the multicomponent hydrogel formulations of besifloxacin and levofloxacin to have superior corneal permeation with the potential for being used as topical ophthalmic preparations. [ABSTRACT FROM AUTHOR]

The purpose of this article is to develop a modern strategy for handling difficulties related to contact lenses and their care. A growing number of people throughout the world are currently concerned by eye-related undesirable activities in allergy sufferers and those wearing contact lenses. While many wearers who experience ocular discomfort exhibit dryness as a symptom, many other contact lens-related pain symptoms also include irritation and fatigue, and managing coexisting diseases must be done in accordance with aspects of wearing contact lenses, all of which undoubtedly increase discomfort. It is typical for contact lens storage containers to have persistent microbial contamination, which has been linked to microbial keratitis (MK) and clear corneal invasion. Contact lens-associated MK is an interesting, potentially sight-threatening complexity arising from wearing soft contact lenses. Estimates show that for every 10,000 persons who wear contact lenses each year, there are 2 to 5 occurrences of MK. Investigating separate determinants for contact lens-associated MK and evaluating their impact on infection load is one of the challenges in their administration. It is hoped that this will offer a useful outline of the complicated issues of contact lens wear that are both infectious and non-infectious. Recent epidemiological studies detailing the risk factors associated with contact lens use, and the effect of pathogen and individual immune profiles on the severity of diseases have enlightened how we might interpret the prophylaxis and prevention of contact lens-related corneal infection. The most dreaded side effect of contact lens use, infectious keratitis linked with contact lenses, will be reviewed, along with the most recent advancements in its diagnosis and treatment., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Waghmare et al.)

Fungal keratitis remains a challenging and often elusive diagnosis in geographic regions where it is endemic. Marred by delays in diagnosis, the sequelae of corneal fungal infections, though preventable, can be irreversible. Recent studies and advances in the arena have broadened the approach and treatment to mycotic keratitis. This review will discuss current diagnostic modalities of fungal keratitis and will particularly focus on treatment regimens. It will also explore future therapeutic models and critique the potential benefit of each. [ABSTRACT FROM AUTHOR]

Copyright of Wiener Klinische Wochenschrift is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Mycotic keratitis is a fungal infection of the cornea. This infection is difficult to treat and it can lead to severe visual impairment or blindness. It is worldwide in distribution, but is more common in the tropics and subtropical regions. Trauma is the major predisposing factor, followed by ocular and systemic defects, prior application of corticosteroids, and prolonged use of antibiotic eye-drops. The objective of this study was to determine causative agents and to identify the predisposing factors of mycotic keratitis. Methodology: Corneal scrapings from 90 corneal ulcer patients with suspected fungal etiology were subjected to direct examination by 10% KOH mount, Gram stain and culture. Results: This study included 90 subjects with corneal ulcers, based on clinical suspicion, of whom 41 cases were diagnosed with mycotic keratitis in the laboratory. Among these 41 cases, culture showed fungal growth only in 36 cases whereas the remaining five cases were positive only by potassium hydroxide (KOH) preparation. Males were more commonly affected and were mostly in the age group of 31-40 years. Aspergillus flavus was the most common fungus isolated followed by fusarium solani. Conclusion: Rapid diagnosis and early institution of antifungal therapy is necessary to prevent ocular morbidity and blindness. Although culture helps in definite diagnosis and identification, direct microscopic detection of fungal structures in corneal scrapes or biopsies permits a rapid presumptive diagnosis. [ABSTRACT FROM AUTHOR]

Corneal ulcers, a leading cause of blindness in the developing world are treated inappropriately without prior microbiology assessment because of issues related to availability or cost of accessing these services. In this work we aimed to develop a device for identifying the presence of Gram-positive or Gram-negative bacteria or fungi that can be used by someone without the need for a microbiology laboratory. Working with branched poly (N- iso propyl acrylamide) (PNIPAM) tagged with Vancomycin, Polymyxin B, or Amphotericin B to bind Gram-positive bacteria, Gram-negative bacteria and fungi respectively, grafted onto a single hydrogel we demonstrated specific binding of the organisms. The limit of detection of the microbes by these polymers was between 10 and 4 organisms per high power field (100X) for bacteria and fungi binding polymers respectively. Using ex vivo and animal cornea infection models infected with bacteria, fungi or both we than demonstrated that the triple functionalised hydrogel could pick up all 3 organisms after being in place for 30 min. To confirm the presence of bacteria and fungi we used conventional microbiology techniques and fluorescently labelled ligands or dyes. While we need to develop an easy-to-use either a colorimetric or an imaging system to detect the fluorescent signals, this study presents for the first time a simple to use hydrogel system, which can be applied to infected eyes and specifically binds different classes of infecting agents within a short space of time. Ultimately this diagnostic system will not require trained microbiologists for its use and will be used at the point-of-care. • Functionalised branched Poly N-isopropyl acrylamide binds corneal ulcer causing microorganisms. • The functionalised polymers demonstrated specific binding to gram positive, gram negative and fungi. • Grafting three different polymers on a single hydrogel retained this specific binding for microorganisms. • Triple functionalised hydrogels were effective in picking up microorganisms in ex-vivo and animal cornea infection models. • Application for a duration of 30 min was sufficient to pick up enough organisms for subsequent identification. [ABSTRACT FROM AUTHOR]

Bacterial infections of the cornea, or bacterial keratitis (BK), are notorious for causing rapidly fulminant disease and permanent vision loss, even among treated patients. In the last sixty years, dramatic upward trajectories in the frequency of BK have been observed internationally, driven in large part by the commercialization of hydrogel contact lenses in the late 1960s. Despite this worsening burden of disease, current evidence-based therapies for BK – including broad-spectrum topical antibiotics and, if indicated, topical corticosteroids – fail to salvage vision in a substantial proportion of affected patients. Amid growing concerns of rapidly diminishing antibiotic utility, there has been renewed interest in urgently needed novel treatments that may improve clinical outcomes on an individual and public health level. Bridging the translational gap in the care of BK requires the identification of new therapeutic targets and rational treatment design, but neither of these aims can be achieved without understanding the complex biological processes that determine how bacterial corneal infections arise, progress, and resolve. In this chapter, we synthesize the current wealth of human and animal experimental data that now inform our understanding of basic BK pathophysiology, in context with modern concepts in ocular immunology and microbiology. By identifying the key molecular determinants of clinical disease, we explore how novel treatments can be developed and translated into routine patient care. • Bacterial corneal infections can cause rapidly fulminant disease and permanent vision loss. • Topical antimicrobials and corticosteroids fail to salvage vision in many patients. • The pathogenesis of bacterial corneal infections involves loss of corneal immune privilege. • Innate immune responses are orchestrated by the corneal epithelium, stromal keratocytes, and resident immune cells. • Novel treatments targeting the molecular bases of infection may improve patient outcomes. [ABSTRACT FROM AUTHOR]

Purpose: We evaluate the in vitro antibacterial activity of silver-copolymerized barrel cases compared to nonsilver barrel cases in combination with a multipurpose disinfecting solution (MPDS)., Methods: The ability of silver and nonsilver cases to reduce the number of adherent Gram-positive and Gram-negative bacteria was assessed. Additionally, the efficacy of silver cases along with MPDS was investigated in the presence of organic soil and contact lenses. Contact lens cases were challenged with 10 6 colony-forming units (CFU)/mL of five bacterial species. Adherent bacteria were dislodged from lens cases and surviving organisms enumerated., Results: Significantly lower numbers of microbes were recovered from silver cases compared to controls, for all bacterial strains ( P < 0.005). The combination of silver case along with MPDS showed added efficacy against Gram-positive and -negative bacteria with a maximum reduction of 3.00 ± 0.5 Log 10 CFU/mL, compared to the efficacy of silver cases alone (1.97 ± 0.4 Log 10 CFU/mL). The addition of organic soil and a contact lens resulted in a significant ( P < 0.005) decrease (a maximum of 1.68 ± 0.2 log 10 CFU/mL) in disinfection efficacy when MPDS and either silver or control cases were used., Conclusions: Silver-copolymerized barrel cases work on conjunction with a hypochlorite producing MPDS in the presence of contact lenses and organic soil to reduce microbial contamination of lens cases., Transitional Relevance: Silver-copolymerized barrel contact lens cases show promising in vitro antibacterial activity against bacterial types commonly implicated in contact lens-related corneal infections. This intervention may limit storage case contamination during use and reduce the frequency of contact lens-related microbial disease.

Introduction: To study antibiotic susceptibility in bacterial keratitis (BK), its profile over 10 years and its influence on ophthalmological practice., Methods: Retrospective review of BK with positive corneal scraping over a 10-year period. Risk factors for keratitis, visual acuity (VA), empirical topical treatment, corneal infection characteristics and outcomes were analyzed for BK due to Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pneumoniae, Pseudomonas aeruginosa and Propionibacterium acnes., Results: 389 positive corneal scrapings were collected. All Gram-positive bacteria were susceptible to vancomycin. P. aeruginosa demonstrated >90% sensitivity to the most-commonly-used topical antibiotics. Susceptibility to methicillin was 90.2% for S. aureus and 66.3% for S. epidermidis. The results of 215 patients were available. 1.9% required enucleation and 2.8% required surgical treatments. Final VA improved after treatment in keratitis due to S. aureus (p=0.026) and S. epidermidis (p=0.005). There was a correlation between S. aureus resistance to methicillin (p=0.002) and levofloxacin (p=0.043) and enucleation (20% and 10%, respectively) compared with a 0% rate of enucleation in S. aureus-susceptible keratitis., Conclusions: BK due to S. pneumoniae is very aggressive irrespective of antibiotic sensitivity. S. aureus was frequently isolated in patients with systemic diseases. It causes severe keratitis and remains moderately resistant to methicillin and levofloxacin. For this reason, keeping vancomycin in empirical regimens is believed to be necessary., (Copyright © 2017 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.)

Aim: To investigate the spectrum and antibiotic susceptibility of bacteria isolated from patients with suspected corneal infections in Zhongshan Ophthalmic Center in South China over the past four years retrospectively., Methods: Totally 1943 corneal scrapes from patients with corneal infections from 2010 to 2013 were cultured and processed using standard microbiological procedures to identify bacterial isolates. Simultaneously, the bacterial isolates were tested for antibiotic susceptibility to 8 antibiotics (ceftazidime, cefuroxim, cefazolin, levofloxacin, ofloxacin, neomycin, tobramycin, chloramphenicol) using the Kirby-Bauer disc diffusion technique., Results: Of the total 1943 scrapes, 397 (20.43%) were culture-positive, of which 294 (74.06%) were gram-positive (GP) and 103 (25.94%) were gram-negative (GN) bacteria. Of the GP organisms, the most prevalent genera were Staphylococcus spp. (56.17%, n=223), Kocuria spp. (5.29%, n=21) and Micrococcus spp. (1.26%, n=5). On the other hand, the most prevalent genera were Pseudomonas spp. (12.85%, n=51), Burkholderia spp. (2.02%, n=8) and Acinetobacter spp. (1.51%, n=6) for the GN organisms. Among five antibiotics that have eye drop products, the resistant to neomycin of GP (7.82%, 95% CI: 4.72%-10.92%) and GN isolates (9.71%, 95% CI: 4.01%-15.41%) was lowest, while the resistant to chloramphenicol was highest (GP: 34.35%, 95% CI: 28.92%-39.78%; GN: 60.19%, 95% CI: 50.74%-69.64%)., Conclusion: Staphylococcus spp. was the most common bacterial pathogens isolated from patients with corneal infections in this setting. High percentages of GP and GN bacteria were mostly susceptible to neomycin and highly resistant to chloramphenicol.