Distribution by Scientific Domains

Kinds of Keratitis

  • acanthamoeba keratitis
  • bacterial keratitis
  • fungal keratitis
  • infectious keratitis
  • microbial keratitis

  • Selected Abstracts

    A rare connexin 26 mutation in a patient with a forme fruste of keratitis,ichthyosis,deafness (KID) syndrome

    Ching Yin Neoh MBBS, MMed(Int Med)
    Background, Keratitis,ichthyosis,deafness (KID) syndrome is a rare ectodermal dysplasia characterized by generalized erythrokeratotic plaques, sensorineural hearing loss, and vascularizing keratitis. Cutaneous changes and hearing loss typically present in early childhood, whereas ocular symptoms present later. Mutations in the connexin (Cx) 26 gene, GJB2, are now established to underlie many of the affected cases, with the majority of patients harboring the p.D50N mutation. Methods, A rare patient demonstrating features of incomplete KID syndrome associated with an uncommon Cx26 gene mutation is described. Results, The patient presented late in adolescence with partial features of KID syndrome. There was limited cutaneous involvement and the rare association of cystic acne. Both hearing impairment and ophthalmic involvement were mild in severity. Genetic mutation analysis revealed a previously described, rare mutation in GJB2, resulting in a glycine to arginine change at codon 12 (p.G12R). Conclusions, This report describes a patient exhibiting characteristics suggestive of a late-onset, incomplete form of KID syndrome with the GJB2 mutation (p.G12R). The p.G12R mutation has only been described in one other patient with KID syndrome, whose clinical presentation was not characterized. [source]

    Germline mosaicism in keratitis,ichthyosis,deafness syndrome: pre-natal diagnosis in a familial lethal form

    CLINICAL GENETICS, Issue 6 2010
    E Sbidian
    Sbidian E, Feldmann D, Bengoa J, Fraitag S, Abadie V, de Prost Y, Bodemer C, Hadj-Rabia S. Germline mosaicism in keratitis,ichthyosis,deafness syndrome: pre-natal diagnosis in a familial lethal form. Keratitis,ichthyosis,deafness (KID) syndrome is an autosomal dominant congenital ectodermal defect characterized by the association of skin lesions, hearing loss and keratitis. Most of the cases appear to be sporadic. KID syndrome is mostly related to mutations of GJB2 gene encoding connexin-26. Recently, a lethal form of the disease during the first year of life has been reported in two unrelated Caucasian patients. This rare lethal form is caused by the G45E mutation of GJB2 gene. We here report the first pre-natal molecular genetic diagnosis of the lethal form of KID syndrome relating to a G45E mutation. In the same family, the occurrence of this condition in three other siblings born to African non-consanguineous healthy parents lead to perform pre-natal diagnosis for this last pregnancy. Molecular analysis confirms the diagnosis of the lethal form of KID for the fetus. These results establish the role of germline mosaicism in KID syndrome and warrant careful genetic counseling. Furthermore, analysis of our cases and the literature allowed us to define a characteristic severe neonatal phenotype including facial dysmorphy, severe cornification with massive focal hyperkeratosis of the skin with erythroderma, dystrophic nails, complete atrichia and absence of foreskin. [source]

    Involvement of Fusarium spp. in fungal keratitis

    I. Dóczi
    Abstract Members of the filamentous fungal genus Fusarium are among the agents most frequently causing keratomycosis in humans. Fusarium keratitis is most common among agricultural workers in geographical regions with hot, humid, tropical or semi-tropical climates, but can occur more rarely in countries with temperate climates, such as Hungary. Keratitis is usually treated with a topical antifungal agent, sometimes in combination with sub-conjunctival injections and/or antimycotic agents, but therapeutic keratoplasty may be needed for patients whose corneal infection does not resolve. Early and accurate diagnosis, coupled with appropriate antifungal therapy, is crucial for improving the chances of complete recovery. [source]

    Clinical findings and outcomes of ulcerative keratomycosis in 30 horses in the mid-Atlantic United States (2006,2007)

    M. E. Utter
    Summary The purpose of this study was to determine the clinical course and outcome associated with keratomycosis in horses in the mid-Atlantic USA. Records of horses diagnosed with keratomycosis at New Bolton Center from November 2006 to November 2007 with positive fungal culture were retrospectively studied. Neither horses with ulcerative keratitis and a negative fungal culture nor those with stromal abscesses were included. Subject details, history, clinical findings, therapy and outcome were recorded. Thirty horses fitted both inclusion criteria (diagnosis of keratomycosis and positive corneal fungal culture). Fourteen of 30 cases occurred during summer. Aspergillus was the most commonly cultured fungal genus (17/30, or 57%) followed by Alternaria (4/30). Seventeen horses had positive bacterial and fungal cultures. Fifteen of 30 horses were treated surgically by a keratectomy and amnion (8) or conjunctival (7) graft. Itraconazole was the most common topical anti-fungal therapy and was utilised in 25/30 horses. Globe survival was 97% (29/30). All surviving globes had a positive menace response and were visual at the last examination. It was concluded that in the mid-Atlantic USA, fungal keratitis is common, has the highest incidence in summer, and is usually associated with a positive outcome. Aspergillus may be a relatively more common corneal pathogen in this region than elsewhere in the USA. Surgical cases were more likely to have fungal hyphae identified on cytology and tended to be hospitalised longer than medical cases. There was no apparent association between surgical disease and all other patient, organism and treatment variables. [source]

    Clinical features and outcomes of severe ulcerative keratitis with medical and surgical management in 41 horses (2000,2006)

    M. E. Utter
    Summary The clinical features and outcomes of equine ulcerative keratitis with and without conjunctival graft surgery were assessed using a retrospective study. Medical records of horses hospitalised from July 2000-January 2006 for ulcerative keratitis were included if a diagnosis of melting ulcer, descemetocele or iris prolapse was made, or if surgery was recommended due to severity of corneal disease, and aggressive medical therapy using a subpalpebral catheter was instituted. Treatment and outcome variables were evaluated with and without conjunctival graft surgery. Forty-one horses, 21 that had surgery and 20 for whom surgery was recommended but not performed, were included. Horses were hospitalised for an average of 24 days, with 37/41 melting ulcers, 17/41 descemetoceles and 3/41 iris prolapses, with no statistical difference in frequencies between groups. Bacterial or fungal organisms were cultured from 22/39 cases, with 10 Aspergillus spp. and 8 Pseudomonas spp. Infectious organisms were seen on corneal cytology in 23/30 cases. Surgical cases were hospitalised for an average of 4.9 days prior to surgery. Abdominal discomfort was observed in 8/41 hospitalised horses, with 5/8 operated horses developing caecal impactions. Thirty-five horses retained an intact globe, including 18/20 treated medically and 17/21 that had surgery. Hospitalisation cost was 24% more for cases that had surgery than for medical cases. It was concluded that there was no statistical difference in length or cost of hospitalisation between surgical and nonsurgical groups. Outcomes from both groups were similar, with a high frequency of globe retention. [source]

    Ocular complications of neurological therapy

    S. Hadjikoutis
    Treatments used for several neurological conditions may adversely affect the eye. Vigabatrin-related retinal toxicity leads to a visual field defect. Optic neuropathy may result from ethambutol and isoniazid, and from radiation therapy. Posterior subcapsular cataract is associated with systemic corticosteroids. Transient refractive error changes may follow treatment with acetazolamide or topiramate, and corneal deposits and keratitis with amandatine. Intraocular pressure can be elevated in susceptible individuals by anticholinergic drugs, including oxybutynin, tolterodine, benzhexol, propantheline, atropine and amitriptyline, and also by systemic corticosteroids and by topiramate. Nystagmus, diplopia and extraocular muscle palsies can occur with antiepileptic drugs, particularly phenytoin and carbamazepine. Ocular neuromyotonia can follow parasellar radiation. Congenital ocular malformations can result from in utero exposure to maternally prescribed sodium valproate, phenytoin and carbamazepine. Neurologists must be aware of potential ocular toxicity of these drugs, and appropriately monitor for potential adverse events. [source]

    A rare connexin 26 mutation in a patient with a forme fruste of keratitis,ichthyosis,deafness (KID) syndrome

    Ching Yin Neoh MBBS, MMed(Int Med)
    Background, Keratitis,ichthyosis,deafness (KID) syndrome is a rare ectodermal dysplasia characterized by generalized erythrokeratotic plaques, sensorineural hearing loss, and vascularizing keratitis. Cutaneous changes and hearing loss typically present in early childhood, whereas ocular symptoms present later. Mutations in the connexin (Cx) 26 gene, GJB2, are now established to underlie many of the affected cases, with the majority of patients harboring the p.D50N mutation. Methods, A rare patient demonstrating features of incomplete KID syndrome associated with an uncommon Cx26 gene mutation is described. Results, The patient presented late in adolescence with partial features of KID syndrome. There was limited cutaneous involvement and the rare association of cystic acne. Both hearing impairment and ophthalmic involvement were mild in severity. Genetic mutation analysis revealed a previously described, rare mutation in GJB2, resulting in a glycine to arginine change at codon 12 (p.G12R). Conclusions, This report describes a patient exhibiting characteristics suggestive of a late-onset, incomplete form of KID syndrome with the GJB2 mutation (p.G12R). The p.G12R mutation has only been described in one other patient with KID syndrome, whose clinical presentation was not characterized. [source]

    Aspergillus flavus: an emerging non- fumigatus Aspergillus species of significance

    MYCOSES, Issue 3 2009
    Suganthini Krishnan
    Summary Invasive aspergillosis is rare in immunocompetent people but contributes to significant morbidity and mortality in immunosuppressed patients. The majority (approximately 80%) of invasive Aspergillus infections is caused by Aspergillus fumigatus. The second most frequent (approximately 15,20%) pathogenic species is Aspergillus flavus and to a lesser extent, Aspergillus niger and Aspergillus terreus. Aspergillus flavus has emerged as a predominant pathogen in patients with fungal sinusitis and fungal keratitis in several institutions worldwide. To date, there has not been any publication exclusively reviewing the topic of A. flavus in the literature. This article reviews the microbiology, toxigenicity and epidemiology of A. flavus as well as describes the clinical characteristics, diagnosis and management of infections caused by this organism. [source]

    Mycotic keratitis: an overview of diagnosis and therapy

    MYCOSES, Issue 3 2008
    P. K. Shukla
    Summary The increased incidence of fungal infections in the recent past has been attributed to the increase in the number of human immunodeficiency virus-positive and AIDS patients. Early diagnosis of mycoses in patients is crucial for prompt antifungal therapy. The yield of clinical examination in the diagnosis of keratomycosis is 63,83% and KOH mount is 91%. This still highlights the limitation of routine clinical examination and smear examination, which is not performing 100% efficiently. It is for these 37%, 17% and 9% of cases, every day advanced technologies are called for. Those who deal with patient care are aware of certainties and uncertainties of results of clinical examination. The best reported figures at specialized centres might not translate into clinical practice. Another factor to be kept in mind is that many patients who come after secondary and tertiary referrals are already treated with antibiotics, antivirals, steroids and sometimes even antifungals that distort the clinical picture completely. Further, one has to consider as well the cases caused by yeast-like fungi, which resemble bacterial keratitis. Confirmation of diagnosis, not only in case of mycotic keratitis but also for other diseases, to initiate prompt and accurate therapy would avoid unnecessary and indiscriminate use of steroids/antibacterials/antivirals and antifungals. [source]

    In vitro and in vivo antifungal activity of cetrimide (cetyltrimethyl ammonium bromide) against fungal keratitis caused by Fusarium solani

    MYCOSES, Issue 1 2007
    Yehia A.-G.
    Summary Mycotic keratitis is a devastating eye infection acquired after eye injury. Cetrimide at 15 and 20 mg ml,1 produced no surviving Fusarium solani growth with minimal inhibitory concentration value of 0.10 mg ml,1. Topical administration of three drops (0.3 ml) of cetrimide aqueous solution of 10 mg ml,1 at pH 6.4 three times daily succeeded to cure human severe resistant F. solani keratitis in a time course of <3 weeks, and with complete healing after 6 weeks. Cetrimide-treated rabbit corneas section appeared with normal compact epithelium and endothelium with no vacuolation in Descemet's endothelial complex: an indication that cetrimide has no significant toxic effects. So, cetrimide at 10 mg ml,1 may be effective and safe topical therapy in patients with mycotic keratitis, especially F. solani ulcers. Currently, there is no antimycotic drug with a good corneal penetration, which is safe and has a fungicidal activity. [source]

    Do multipurpose contact lens disinfecting solutions work effectively against non-FDA/ISO recommended strains of bacteria and fungi?

    Maureen Boost
    Abstract Purpose:, Recent outbreaks of microbial keratitis have increased concerns about the efficacy of multipurpose solutions (MPS) against ,real-world' organisms. This study determined, in accordance with FDA/ISO standard methods, the effects of five MPS against clinical isolates and type strains of bacteria, and isolates of fungi from subjects' ocular structures; and of three MPS against environmental fungal isolates. Method:, MPS were challenged with bacteria (type strains (ATCC) and clinical isolates of bacterial pathogens obtained from a district hospital laboratory) and with fungal isolates from both the periocular and conjunctival structures and from environmental air. Results:, All MPS demonstrated at least a 3-log reduction of challenged cell viability of all bacterial species tested, with the exception of MPS D against a canine infection Staphylococcus aureus isolate. Whilst all MPS tested were able to effect a 1.0-log reduction of viability of Fusarium solani (ATCC 36031), only two MPS had 90% viability reduction against all fungi of human origin and only one of these against all environmental fungal isolates. Effectiveness of these two solutions against fungal isolates compared to the remaining three MPS was found to be statistically significant (p = 0.003). Conclusions:, All MPS demonstrated a 99.9% viability reduction against a wide range of bacteria including major ocular pathogens not currently included in the FDA panel. The inability of three MPS to achieve a 90% reduction against fungal isolates is of concern as there has been a recent upsurge in reports of fungal keratitis. We would recommend extension of the current FDA testing panel for MPS to include more fungal isolates. [source]

    Infectious keratitis related to orthokeratology

    Xuguang Sun
    Abstract Purpose:, To report 28 cases of infectious keratitis related to orthokeratology lens overnight wear in China. Methods:, From March 2000 to August 2001, 28 cases of infectious keratitis related to overnight orthokeratology lens wear were diagnosed in Beijing Institute of Ophthalmology. These were retrospectively reviewed with regard to the pathogens isolated, duration of wear, the time since onset of symptoms, and age. Cultures of corneal scrapes for bacteria, fungus and Acanthamoeba were performed in all of the 28 cases. Results:, All cases were students, including 10 males and 18 females, average age was 16 years (range 10,21 years). The duration of orthokeratology overnight wearing was from 2 weeks to 2 years. Uncorrected visual acuity (UCVA) on initial examination in our institute was from 20/200 to light perception. Of 28 isolates, 24 were culture positive (including 11 bacteria, 11 Acanthamoeba and two fungi), and four were culture negative. In two of the four culture negative cases, Acanthamoeba cysts were detected in the corneal stroma with the confocal microscope. Acanthamoeba and Pseudomonas aeruginosa accounted for 75% (21 of 28) of the cases of infectious keratitis. Conclusion:, Infectious keratitis is a severe complication associated with overnight orthokeratology lens wear. Ophthalmologists should pay more attention to this complication in practice. [source]

    Trichothiodystrophy-like Hair Abnormalities in a Child with Keratitis Ichthyosis Deafness Syndrome

    L. De Raeve M.D., Ph.D.
    It appears to be genetically heterogeneous and may be caused by mutations in the connexin 26 (Cx26) gene (GJB2) or in the connexin 30 gene. It is characterized by the association of ichthyosis-like skin lesions, hearing loss, and vascularizing keratitis. We report the clinical and molecular findings in a 5-year-old girl with keratitis ichthyosis deafness syndrome. DNA sequencing in our patient revealed a p.Ser17Phe mutation in GJB2. Besides the typical clinical features of keratitis ichthyosis deafness syndrome, a peculiar intriguing finding not previously described in the literature in this condition was that polarizing light microscopy of the scalp hair in our patient revealed striking bright and dark bands as seen in trichothiodystrophy. Amino acid analysis of the hair sample also disclosed a reduced cysteine index. We emphasize that it would be of great benefit to examine hair shafts in other patients with keratitis ichthyosis deafness syndrome for trichothiodystrophy-like abnormalities. [source]

    Characterization of Acanthamoeba Isolates from Dust of a Public Hospital in Curitiba, Paraná, Brazil

    ABSTRACT. Occurrence of Acanthamoeba in the hospital environment may represent a health risk for patients, since these organisms can cause severe opportunistic illness, such as keratitis, and also can harbor pathogenic agents. We analyzed the dust from some environments of a public hospital in Curitiba, Parana State, Brazil. Two distinct populations of Acanthamoeba were isolated in five locations and morphologically classified as group I and group II according to Pussard and Pons. Isolates were identified as Acanthamoeba by PCR using primers to amplify a region of 18S rDNA, which showed variation in the product length among the isolates. A cloned culture of group II showed greater growth at 37 °C and in media with 0.1, 0.5, and 1.0 M mannitol, which are the physiological characteristics of pathogenic Acanthamoeba. Monitoring the presence of Acanthamoeba in hospital units, as well as evaluating the pathogenicity of the isolates, can be an approach to alert the health professionals to improve the disinfection procedures and minimize the risks of treating this problematic disease caused by this protozoan. [source]

    Can propofol cause keratitis?

    ANAESTHESIA, Issue 10 2001
    H. Ameen
    No abstract is available for this article. [source]

    A mutation in NF,B interacting protein 1 causes cardiomyopathy and woolly haircoat syndrome of Poll Hereford cattle

    ANIMAL GENETICS, Issue 1 2009
    M. A. Simpson
    Summary Cardiomyopathy and woolly haircoat syndrome (CWH) of Poll Hereford cattle is a lethal, autosomal recessive disorder. Cardiac and haircoat changes are congenital, neonatal ocular keratitis develops in some cases and death usually occurs within the first 12 weeks of life. We undertook a homozygosity mapping approach to identify the chromosomal location of the causative gene. Seven candidate genes were examined for homozygosity in affected animals: desmoplakin and junction plakoglobin (both previously implicated in human cardiocutaneous syndromes), desmocollin 2, desmoglein 2, plakophilin 2, nuclear factor kappa B (NFKB1) and NF,B interacting protein 1 (PPP1R13L, also known as NKIP1). Homozygosity in 13 affected animals was observed at the PPP1R13L locus, located on bovine chromosome 18. Subsequent sequence analysis revealed a 7-bp duplication (c.956_962dup7) in exon 6 of this 13-exon gene. This frameshift variant is predicted to result in the substitution of three amino acids and the introduction of a premature stop codon at position 325 of the protein product (p.Ser322GlnfsX4). PPP1R13L interacts with NF,B, a family of structurally related transcription factors that regulate genes controlling inflammation, immune responses and cell proliferation and survival. CWH represents a large-animal model for cardiocutaneous disorders caused by a mutation in the PPP1R13L gene. The identification of this bovine mutation also indicates that PPP1R13L and other genes affecting NF,B activity may be candidate genes in the study of human cardiovascular disease. [source]

    1212: Herpes simplex and zoster keratitis

    Herpes simplex virus (HSV) and varicella-zoster virus (VZV) are two leading causes of corneal infection with potential severely impaired visual acuity. These two viruses share multiple characteristics, including the ability to become latent in the trigeminal ganglia, before reactivation and migration along the trigeminal fibers innervating the cornea. The clinical settings of keratitis may vary from an epithelial defect (dendritic of geographic) to a more severe disease involving the stroma and/or the endothelium. Classically, HSV keratitis occurs from the second decade of life, and associated skin disease is not frequent and only involves the eyelids. In contrast, VZV keratitis mostly occurs after the sixth decade, as an associated finding of herpes zoster ophthalmicus (HZO). However, several studies recently highlighted that the rate of HSV keratitis increases with age, even in elderly, and some other studies reported VZV keratitis in children, either isolated or associated with HZO. Antiviral drugs currently available are highly efficient to reduce the severity on ongoing HSV- or VZV keratitis, but preventive treatments still have to be optimized. For HSV keratitis, the usual preventive treatment, as defined by the HEDS study, only reduces the rate of relapses in a two-fold manner, and the optimal dosage has not been settled for patient with severe herpetic disease. For VZV, the two vaccines against chickenpox and HZO probably will lead in the future to a reduction of the incidence of keratitis, but they are not widely used, even in most of developed countries. [source]

    2211: The utility of a rabbit model of adenovirus ocular infection

    Acute adenovirus ocular infections are the most common ocular viral infections worldwide and are associated with community and medical facility epidemics. While not permanently blinding, ocular adenoviral infections are associated with significant patient morbidity, including symptomatic distress with visual disturbances which can last years, and loss of time from school or work. Currently, the treatment of these acute infections is symptomatic due to the lack of an approved antiviral. This symptomatic treatment presents a controversy of whether to treat these viral infections with immunomodulating agents (e.g. topical corticosteroids, NSAIDs, cyclosporine A), which are contraindicated for use in the treatment of the other major external ocular viral infection, HSV-1 epithelial keratitis. The adenovirus type 5 (Ad5)/New Zealand White (NZW) rabbit ocular model has provided data for potential clinical guidelines for the use of immunomodulating agents in the treatment of adenovirus ocular infections. Moreover, this model has been used extensively to evaluate promising candidate antivirals for adenovirus. Multiple candidate antivirals have been evaluated in vivo using this model, and several have proceeded to human clinical trials. The current presentation will discuss the potential clinical guidelines for the use of immunomodulating agents, present data on potential new topical antiviral agents, discuss the potential combination therapy of an antiviral and immunomodulatory agent in the treatment of adenovirus ocular infections as well as the limitations of the model. Commercial interest [source]

    2212: Animal models for vaccinia virus keratitis

    Purpose Studies on pathogenic mechanisms involved in viral ocular infections and testing of potential therapies requires well established quantitative animal models. We present a new model of Vaccinia virus keratitis. Methods Rabbits were infected with the Dryvax strain of Vaccinia virus and disease was scored using a modified MacDonald-Shadduck scoring system. The model will be described and examples of the use of the model for studies of pathogenesis and testing therapeutic approaches will be presented. Results The optimum dose of virus was determined (10e5 PFU). Infiltration of neutrophils followed predominantly by CD4+ cells occurred in the cornea and the optimum therapy was determined to be topical viroptic 9 times per day for 10 days. Steroid use should be avoided. Conclusion A new model of Vaccinia keratitis has been developed that is useful for pathogenesis and therapeutic studies. Commercial interest [source]

    2213: Herpetic keratitis: Herpes simplex virus versus host

    Herpes simplex virus type 1 (HSV-1) is an endemic virus worldwide that causes ocular disease in a limited but significant number of infected persons. Corneal HSV-1 infection is clinically classified into herpetic epithelial keratitis (HEK) and herpetic stromal keratitis (HSK). HEK is an acute inflammation and results from viral toxicity of infected corneal epithelial cells. In contrast, HSK is characterized as a chronic immunopathogenic disease in which tissue injury and eventually blindness is due to the complex interplay between cells of the innate and adoptive immune response to viral antigens expressed in the corneal tissue. Studies performed on the experimental HSK mouse model greatly improved our understanding of the pathogenesis of HSK. This talk will recapitulate current insights on the virus-host interactions involved in the initiation and perpetuation of herpetic keratitis in mice and men. [source]

    2215: Animal models of herpetic retinitis

    The Herpes simplex virus (HSV) is characterized its ability to replicate in the nervous system, before inducing a latent infection with potential reactivation. Most frequent ocular complications of recurrent HSV infection are keratitis and conjunctivitis. Less frequently, the iris and the ciliary body may also be involved (anterior uveitis). The most severe HSV ocular infection is retinitis, a rare but potentially blinding disease, due to frequent bilateral involvement. Studies on human post-mortem tissues showed that HSV is widely distributed in the population, with a preferential location within the trigeminal ganglions (innervating the cornea), but also in the superior cervical ganglions (innervating the iris) or in brain/medullar tissues (innervating the retina). Animal models have been developed to understand the pathogenic processes that lead to this rare but devastating retinal disease. Since human is the only natural host of HSV, it is difficult to obtain a perfect animal model that perfectly mimics the disease. Several animal models, based on different inoculation procedures, are thus necessary to circumscribe the anatomical, cellular and molecular aspects that lead to retinal infection. Finally, HSV retinitis appears as a clinical condition that is highly constrained by the relationships between the strain of the virus and the immune response of the host. [source]

    3131: Endothelial involvement indicates disease activity in Herpes simplex virus keratitis

    Purpose Corneal endotheliitis is a potentially sight-threatening clinical manifestation of herpes simplex virus (HSV) keratitis. Early detection and consequent treatment may prevent development of endothelial decompensation. The goal of this previously published study was to describe the morphological features, frequency, and clinical consequences of endothelial involvement in HSV keratitis as seen by in vivo confocal microscopy (IVCM). Methods We examined both eyes of 250 patients with HSV keratitis by slit-lamp and IVCM. All examinations were assessed for endothelial deviations characteristic of endotheliitis. To determine the specificity, we reviewed our IVCM database for morphologically comparable alterations. This database included 200 healthy volunteers and 1400 patients with various corneal pathologies. The endothelial cell density (ECD) change between the first and last visits of patients with HSV keratitis was evaluated. Results Endotheliitis-specific deviations were detected in 107 of 250 patients with HSV keratitis (43%). Pseudoguttata, enlarged intercellular gaps, infiltration of inflammatory cells into the endothelial layer, loss of defined cell boundaries, spot-like holes, and endothelial denudation disappeared within 3 weeks with appropriate antiviral and anti-inflammatory treatment. Alterations were non-specific for HSV keratitis. Similar alterations were detected in adenoviral, fungal, bacterial, and acanthamoeba keratitis. The HSV affected eyes with endothelial involvement showed a mean ECD decrease of 10.3% per year. Conclusion Endothelial involvement indicates inflammatory activity in HSV keratitis and is associated with irreversible endothelial cell loss. IVCM allows early detection and follow up of endotheliitis-specific alterations. [source]

    Bacterial keratitis: the clinical problem


    Animal models for the treatment of bacterial keratitis

    Rabbit models of bacterial keratitis have been used to evaluate the efficacy of anti-infectives in the clinical treatment of bacterial keratitis. These models can determine: 1) ocular toxicity and tolerance of anti-infectives to ocular tissue, 2) penetration of anti-infectives into the cornea, and 3) anti-bacterial efficacy of the anti-infectives to corneal bacterial pathogens. The current presentation will cover the structure and limitations of rabbit bacterial keratitis modeling using published data. Topics will include statistical design, the choice of bacterial pathogens, and positive aspects for possible systemic anti-infective development. [source]

    The use of animal models for the evaluation of ocular antiviral agents

    Animal models have been used extensively in the evaluation and development of topical ocular antiviral agents. Rabbit ocular models have proven predictive of the clinical efficacy of topical antiviral agents for HSV-1 epithelial keratitis and in clinical trials for adenoviral ocular infections. The current presentation will discuss the limitations of these models and present data on potential new topical antiviral agents, focusing primarily on antivirals for adenoviral ocular infections. [source]

    In vivo confocal microscopic evaluation of inflammatory changes in the ocular surface

    Purpose The ocular surface constitutes a complex physiopathological and anatomical entity assuring the barrier between the outside world and the fragile ocular structures. Ophthalmic instruments such as the slit lamp, which magnifies approximately 40 times, cannot provide details of the corneal structures at the cellular level. Methods In vivo confocal microscopy using the HRT Rostock Cornea module® (HRT / RCM) provides better resolution and therefore outlines distinctively in vivo inflammatory changes occurring in the ocular surface. Results In vivo confocal microscopy is capable of providing corneal, conjunctival and limbal cellular details in different ocular surface diseases such as dry eye, infectious keratitis, toxic keratitis, corneal intraepithelial neoplasia or vernal keratoconjunctivitis. Conclusion In correlation with ex vivo impression cytology analysis, in vivo confocal microscopy constitutes an interesting aid in the diagnosis and management of complex ocular surface conditions. [source]

    Biosynthetic corneas , evaluation in humans

    Collagen-based biosynthetic corneas, designed to mimic the extracellular matrix of the corneal stroma have been developed and extensively evaluated in animal models over the last 7 years. Human recombinant collagen type III (RHC III) was crosslinked with water-soluble carbodiimides and fabricated into optically transparent corneal substitutes for transplantation. Following study approval of the Medical Product Agency, Sweden and the Human Ethics Committee, University of Linköping, Sweden, a Phase I study was initiated. 10 patients who were scheduled for corneal grafting were enrolled into the study. Nine had keratoconus and one had a deep scar following Pseudomonas keratitis. A central 6 mm diameter deep lamellar button was excised and was replaced by a 6.25 mm diameter 500 µm thick construct. Six overlying sutures were used to anchor the graft. Topical 0.1% dexametasone and chloramphenicol was used for the first 1 month postoperatively. The sutures were removed after 5-7 weeks. The patients were followed clinically and evaluated for UCVA, BSCVA and VA with contact lenses. Corneal touch sensitivity (Cochet-Bonnet) and tear production (Schirmer ) were tested. Photography, OCT (Visante), topography (Orbscan II) and in vivo confocal microscopy (Heidelberg) was documented. After 3 months all patients had stably epithelialized and implants were anchored by recipient keratocyte ingrowth. The mean BSCVA at 6 months (20/133) improved slightly at 12 months (20/90). The mean BCLCVA was 20/50 at 12 months and was notably better in younger patients (mean of 20/40 in the 5 youngest). One patient had BCLVA of 20/20 at 12 months. The mean central corneal thickness was stable between 3 and 12 months at about 400µm. The mean 5min Schirmer values were 20 ± 10mm in operated eyes and 17 ± 8 mm in fellow eyes. At 12 months the mean touch sensitivity was 25mm in operated eyes and 60mm in fellow eyes, which was the same as in penetrating grafts. In-vivo confocal microscopy revealed the ingrowth of corneal nerves at the subbasal epithelium. We have shown for the first time that bioengineered collagen-based corneal substitutes are fully compatible and promote regeneration of corneal cells. The 18 months follow-up results will be presented aswell. [source]

    Ophthalmic microsporidiosis: the Manchester experience

    Purpose We report cases of ocular and adnexal microsporidiosis diagnosed in Manchester, UK, and review the literature. Methods The archives of the National Specialist Ophthalmic Pathology (NSOPS) Manchester Laboratory and Health Protection Agency Laboratory (HPA)at Manchester Royal Infirmary were reviewed for cases of microsporidiosis between 1990 and 2009. Results 8 cases of ocular and adnexal microsporidiosis were identified. Organisms were Encephalitozoon hellem, Encephalitozoon sp., Vittaforma corneae, Trachipleistophora hominis, Nosema sp. with infection of ocular surface, cornea, nasolacrimal apparatus and nasal sinuses, and eyelid; a historical case of Microsporidium ceylonensis keratitis, first reported by Norman Ashton in 1973 was also reviewed. Ages ranged from 11 years (Ashton's case) to 50 years. One case was from an HIV +ve patient, the others were immunocompetent. At least 4 infections were contracted whilst the patient was outside the UK. Conclusion Microsporidia, minute obligate intracellular parasites related to fungi, infect via a polar tube housed within a highly resistant spore. Microsporidial infection in HIV/AIDS, usually entereic, is the most reported. Antiretroviral treatment has lowered the incidence of enteric microsporidiosis and ocular infection is increasingly prevalent and often not HIV-related. In our cases the majority were immunocompetent individuals. LM can be diagnostic if characteristic refractile ZN-positive spores are seen, but LM does not permit speciation, which usually requires EM. Diligent searching for organisms may be necessary as distribution may be focal. Insufficient data exist for PCR-based diagnosis of most microsporidial species.Sources and mechanisms of microsporidial infection remain speculative. [source]

    An epidemiologic analysis of staphylococcus aureus-associated keratitis in Boston

    Purpose S. aureus is a normal commensal of the human skin and nasopharynx. It is therefore of interest to determine whether S. aureus keratitis is caused by a subset of these organisms. In this study, the phenotypic and genotypic characteristics of S.aureus keratitis isolates were analyzed. Methods All S. aureus clinical isolates were prospectively collected over a 24 month period at the MEEI (2006-2008). The diagnosis of clinical keratitis and associated risk factors was by medical record review. Keratitis-associated S. aureus strains were assessed for: 1) antibiotic susceptibility, 2) biofilm robustness by gentian violet staining using an in vitro microtiter plate assay, and 3) genetic lineage by multi-locus sequence typing (MLST). Results 26 cases of keratitis were identified from the 600 S. aureus clinical isolates. Risk factors associated with S.aureus keratitis included trauma, prior surgery, soft contact lens wear, and the presence of a foreign body. Ocular surface disease does not appear to be an independent risk factor. All 26 isolates were tetracycline- and trimethoprim-sulfamethoxazole- sensitive. All the MRSA strains were found to be ciprofloxacin-resistant (10/26). Nearly one-half of all the S.aureus keratitis-associated isolates were caused by a single clone, ST5. Both methicillin sensitive and resistant S. aureus strains were represented within ST5. Conclusion These results suggest that there may be specific S.aureus lineages which possess phenotypic and genotypic characteristics that enable S. aureus to more effectively cause sight-threatening keratitis. Future work will examine their virulence traits and a comparison to commensal S.aureus strains. [source]

    Corneal and conjunctival findings after mitomycin C application in pterygium surgery: an in-vivo confocal microscopy study

    Andrey Zhivov
    Abstract. Purpose:, To perform a qualitative assessment of the topical side-effects of mitomycin C on cornea after pterygium surgery. Methods:,In-vivo confocal microscopy (Heidelberg Retina Tomograph II in combination with the Rostock Cornea Module) was performed in 10 patients with unilateral primary pterygium. Mitomycin C 0.02% was applied topically to seven eyes for 5 min intraoperatively and twice daily for 5 days postoperatively. Three eyes underwent surgery without application of cytostatic agent. Patient follow-up was 1 month. Results:, After application of mitomycin C, complete epithelialization of the operated zone was found 2 weeks after surgery. In-vivo confocal microscopy revealed signs of superficial punctate keratitis for 2 weeks in the central cornea only after application of mitomycin C. The presence of epithelial and stromal oedema in this group was noted for up to 2 weeks in the central cornea and for up to 4 weeks in the operated zone. In the control group, complete epithelialization was found after 1 week; there were no signs of oedema after 1 week in the central cornea or after 2 weeks in the operated zone. Leucocyte infiltration and increased Langerhans cell density were noted in both groups in the operated and central zones. Analysis of the conjunctiva revealed a decrease in goblet cell density following cytostatic application. Conclusion:, Local application of mitomycin C delays corneal epithelialization, and prolongs postoperative epithelial and stromal oedema in both the centre and periphery. Moreover, signs of punctate keratitis were noted 2 weeks after surgery in central intact cornea. Nevertheless, in-vivo confocal microscopy shows that these changes are reversible 4 weeks after application of mitomycin C 0.02%. [source]