Neisseria gonorrhoeae keratoconjunctivitis

Clinical and laboratory findings of 47 patients with ocular infections secondary to Neisseria gonorrhoeae during a 5 1/2-year period were reviewed. In 16 patients (34%), corneal involvement was noted. Six of these patients had a severe ulcerative keratitis resulting in permanent visual loss and five required surgery for a corneal perforation. Patients with corneal involvement were older and presented later in the course of their disease than patients with isolated conjunctival involvement (P less than 0.005). An out-patient regimen of intramuscular antibiotics (either penicillin, cephalosporin, or spectinomycin [Trobicin]) appeared to be effective for infections limited to the conjunctiva in adults. If a topical antibiotic ointment is used in addition to parenteral antimicrobial agents, the authors' laboratory sensitivities suggest that erythromycin may be the drug of choice.     

Paradox of complex diversity: Challenges in the diagnosis and management of bacterial keratitis

Bacterial keratitis continues to be one of the leading causes of corneal blindness in the developed as well as the developing world, despite swift progress since the dawn of the “anti-biotic era”. Although, we have expeditiously developed our understanding about the different causative organisms and associated pathology leading to keratitis, extensive gaps in knowledge continue to dampen the efforts required for early and accurate diagnosis, and management in these patients, resulting in poor clinical outcomes. The ability of the causative bacteria to subdue the therapeutic challenge stems from their large genome encoding complex regulatory networks, variety of unique virulence factors, and rapid secretion of tissue damaging proteases and toxins.In this review article, we provide an overview of the established diagnostic techniques and therapeutics for keratitis caused by various bacteria. We extensively report the recent in-roads through novel tools for accurately diagnosing mono- and poly-bacterial corneal infections. Furthermore, we outline the recent progress by our groups and others in understanding the sub-cellular genomic changes that lead to antibiotic resistance in these organisms. Finally, we discuss in detail, the novel therapies and drug delivery systems in development for the efficacious management of bacterial keratitis.     

Voriconazole in the management of Alternaria keratitis

PURPOSE: To discuss the role of voriconazole in the management of Alternaria keratitis. METHODS: Case report and literature review. RESULTS: A 69-year-old man with a history of corneal foreign body removal developed a stromal infiltrate 2 months later that did not improve despite topical antibiotics and natamycin. On our initial examination, visual acuity (VA) was 20/40, and he had a central, full-thickness, reticular appearing infiltrate. Oral clarithromycin was added because of the atypical pattern of the infiltrate. However, no improvement was noted. A repeat culture revealed coagulase-negative Staphylococcus. VA decreased to 20/200, and increased inflammation was noted a month later; a trial of topical steroids was added. After an initial improvement, he returned with progression. Repeat culture revealed Alternaria species, and topical amphotericin was started. When there was no response, he was admitted and switched to oral and topical voriconazole. Steady resolution was noted within 10 days of therapy. CONCLUSION: Suspicion must be maintained for unusual causes of infectious keratitis. Fungal infection can be difficult to eradicate even with traditional antifungals. Although not approved for ophthalmic use yet, voriconazole provided improvement with Alternaria keratitis unresponsive to amphotericin.     

Update on the management of fungal keratitis

Purpose

The aim of this article is to introduce the recent advance on the studies of fungal keratitis published over past 5 years.

Methods

We performed literature review of articles published on PubMed, Google Scholar, CNKI and Web of Science relevant to the diagnosis, pathogenesis and novel treatment of fungal keratitis.

Results

Excessive inflammation can lead to stromal damage and corneal opacification, hence the research on immune mechanism provides many potential therapeutic targets for fungal keratitis. Many researchers discussed the importance of earlier definitive diagnosis and were trying to find rapid and accurate diagnostic methods of pathogens. Develop new drug delivery systems and new routes of administration with better corneal penetration, prolonged ocular residence time, and better mucoadhesive properties is also one of the research hotspots. Additionally, many novel therapeutic agents and methods have been gradually applied in clinical ophthalmology.

Conclusion

The diagnosis and treatment of fungal keratitis are still a challenge for ophthalmologist, and many researches provide new methods to conquer these problems.

     

Corneal biopsy in the management of progressive microbial keratitis

PURPOSE: To study the indications and role of diagnostic corneal biopsy in the management of patients with progressive microbial keratitis. METHODS: The records of 33 consecutive patients who underwent a diagnostic corneal biopsy from January 1, 1986, to December 31, 1998, were reviewed. The indication for corneal biopsy was progressive infectious keratitis despite intensive broad-spectrum topical antimicrobial therapy, or progressive stromal infiltration inaccessible to corneal scrapings. Microbiologic evaluation of all corneal biopsies was performed, and 11 of the 33 biopsies were also examined histopathologically. RESULTS: A microorganism was isolated from 27 (82%) of the 33 corneal biopsies. Of the six patients with a negative biopsy, a penetrating keratoplasty was performed in five patients and the pathogen was identified by examination of the corneal button. In one patient no microorganism was identified; however, the infection resolved with topical antimicrobial therapy. The most common risk factor for keratitis was foreign body exposure or corneal abrasion (14 patients). A solid stromal infiltrate was the most common pattern of corneal involvement. Corneal biopsy revealed previously unidentified microorganisms that led to a change in antimicrobial therapy in 24 (89%) of the 27 patients and confirmed prior culture results in the remaining 3 patients. Microbiologic evaluation of the corneal biopsy was more sensitive than histopathologic examination. Acanthamoeba was the most commonly isolated pathogen (five cases), followed by Propionibacterium acnes and Fusarium (four cases each). Gram-positive organisms were isolated in 16 patients. Only five of the 27 patients with a positive corneal biopsy required a penetrating keratoplasty, in contrast to five of the six patients with a negative corneal biopsy (P =.005). During the 13-year period of the study, only three corneal biopsies were performed in the last 6 years. CONCLUSIONS: Microbiologic evaluation of a diagnostic corneal biopsy contributed significantly to the diagnosis, treatment, and outcome of patients with progressive infectious keratitis.     

Causes and management of bacterial keratitis in the elderly

The author evaluated 142 patients aged 65 years or older with microbial keratitis. There were relatively high rates of Pseudomonas aeruginosa infection unassociated with contact lens wear and of Streptococcus pneumoniae infection. The rates of quasicommensal and enteric infections were not proportionately elevated. Corneal disease, use of topical corticosteroids and use of contact lenses were the main predisposing factors. Patients with diabetes mellitus, dementia or chronic alcoholism appeared to be at higher risk. Trauma was rarely a factor. Complications requiring surgery were common. Corneal perforation developed in 20% of the patients, and endophthalmitis developed in 6%. The elderly often do not tolerate intensive topical antibiotic treatment well. Supplementary subconjunctival antibiotic injections under local anesthesia may be necessary. Corneal tissue glue, tarsorrhaphy and conjunctival flaps are probably underused in this age group.     

新时期细菌性角膜炎的临床处置要点

细菌性角膜炎是常见的感染性角膜炎,多数患者即使治愈后也会有严重的视力损害.由于病原菌耐药性的逐渐增强,现有抗生素对细菌性角膜炎的治疗效果越来越差.面对这一挑战,本文从诊断和治疗的角度将近年来细菌性角膜炎的临床处置经验进行了概述.除对感染灶标本取材、常见培养基和抗生素选择的共识进行了归纳和总结外,还介绍了一种有效且实用的,治疗严重、顽固性眼表感染的眼睑下抗生素持续灌注给药方法.