Mechanisms Underlying Contact Lens-Related Keratitis Caused by Pseudomonas aeruginosa.

ABSTRACT: Infectious keratitis is a severe complication associated with contact lens (CL) wear, and can progress rapidly with suppurative infiltration, resulting in the loss of vision. Contact lens wearers with poor and improper care are susceptible to develop infectious keratitis. Gram-negative bacilli such as Pseudomonas aeruginosa, have an ability to form biofilms on CL cases and CLs. Moreover, P. aeruginosa has various virulence factors such as type III secretion system (TTSS) which is an important factor for pathogenicity in keratitis. The effector proteins of TTSS have been identified, namely ExoU, ExoS, ExoT, and ExoY. Pseudomonas aeruginosa strains with ExoU show resistance to disinfection. The strains isolated from CL-related keratitis have higher ExoU gene positivity. Expression of elastase and swarming motility of P. aeruginosa isolates significantly correlates with focus size of keratitis. In addition to education of lens care for the CL wearer, development of CL cleaning solutions targeting suppression of virulence factors are needed for prevention of CL-related keratitis in the future.

Increased Rate of Infectious Keratitis After PRK in the COVID-19 Era: The Possible Role of Face Masks.

PURPOSE: To evaluate the rate of infectious keratitis after photorefractive keratectomy (PRK) before and during the coronavirus disease 2019 (COVID-19) pandemic. METHODS: A retrospective chart review was performed on patients who were diagnosed as having infectious keratitis after PRK between January 2015 and January 2021. RESULTS: The study period was divided into the pre-COVID-19 era (between January 2015 and February 2020) and the COVID-19 era (between February 2020 and January 2021). A total of 47 patients were diagnosed as having infectious keratitis after PRK: 22 were diagnosed in the pre-COVID-19 era and 25 were diagnosed in the COVID-19 era. The rate ratio for infectious keratitis after PRK was 5.68 during the COVID-19 pandemic (CI: 3.20 to 10.07, P < .001). The odds ratio for the ratio of cases of infectious keratitis after PRK to all cases of infectious keratitis was 9.00 during the COVID-19 pandemic (CI: 5.05 to 16.05, P < .001). To better understand the change in the rate of infectious keratitis after PRK during the COVID-19 pandemic, the analysis was narrowed to the patients with infectious keratitis who had their procedure in Farabi Eye Hospital. Of the 8 patients who were diagnosed as having infectious keratitis after PRK, 4 were diagnosed in the pre-COVID-19 era and 4 were diagnosed in the COVID-19 era. The risk ratio of infectious keratitis after PRK was 9.11 in our department in the COVID-19 era (95% CI limit: 2.28 to 36.46, P = .005). CONCLUSIONS: The rate of infectious keratitis after PRK increased during the COVID-19 pandemic. This may be due to the increased use of face masks in this era. [J Refract Surg. 2022;38(2):78-81.].

Increased photokeratitis during the coronavirus disease 2019 pandemic: Clinical and epidemiological features and preventive measures.

ABSTRACT: An increased incidence of photokeratitis has occurred during the coronavirus disease 2019 (COVID-19) pandemic due to improper and unprotected use of ultraviolet lamps. Here, we summarize the clinical and epidemiological features of this increased incidence of photokeratitis and share advice in using health education to prevent it.We collected data from patients diagnosed with photokeratitis from October 7, 2019 to December 1, 2019, and from February 17, 2020 to April 12, 2020, and compared the frequency of onset, site of ultraviolet radiation (UVR) exposure, reason for exposure, exposure time, and recovery time. We also implemented and evaluated multiple measures of public health education to prevent increased disease.After the COVID-19 outbreak, the frequency of onset of photokeratitis increased significantly, especially among young women. The main reason for UVR exposure changed from welding to disinfection. The incidence sites varied, and the exposure time was longer. As a result, patients needed a longer time to recover. Positive health education was an useful and convenient measure to prevent the disease.While the COVID-19 pandemic is ongoing, more attention should be paid to public health and implement positive measures to prevent photokeratitis.

UV-Photokeratitis Associated with Germicidal Lamps Purchased during the COVID-19 Pandemic.

PURPOSE: To report photokeratitis caused by the improper use of germicidal lamps purchased during the COVID-19 pandemic. METHODS: Case series. RESULTS: Seven patients presented with acute ocular surface pain after exposure to UV-emitting germicidal lamps. Visual acuity was 20/30 or better in 13 of 14 eyes (93%). Anterior segment examination revealed varying degrees of conjunctival injection and diffusely distributed punctate epithelial erosions (PEEs) in every patient. No intraocular inflammation was identified across the cohort and all fundus examinations were normal. Treatment varied by provider and included artificial tears alone or in combination with antibiotic ointments and/or topical steroids. Five patients were followed via telehealth, one patient returned for an in-office visit, and one patient was lost to follow-up. Five of six patients endorsed complete resolution of symptoms within 2-3 days. CONCLUSIONS: Patients should follow manufacturer recommendations when using UV-emitting germicidal lamps and avoid direct exposure to the ocular surface.

Ocular Complications in the Prone Position in the Critical Care Setting: The COVID-19 Pandemic.

PURPOSE: Ocular complications are common in the critical care setting but are frequently missed due to the focus on life-saving organ support. The SARS-CoV-2 (COVID-19) pandemic has led to a surge in critical care capacity and prone positioning practices which may increase the risk of ocular complications. This article aims to review all ocular complications associated with prone positioning, with a focus on challenges posed by COVID-19. MATERIALS AND METHODS: A literature review using keywords of "intensive care", "critical care", "eye care", "ocular disorders", "ophthalmic complications," "coronavirus", "COVID-19," "prone" and "proning" was performed using the electronic databases of PUBMED, EMBASE and CINAHL. RESULTS: The effects of prone positioning on improving respiratory outcomes in critically unwell patients are well established; however, there is a lack of literature regarding the effects of prone positioning on ocular complications in the critical care setting. Sight-threatening ophthalmic disorders potentiated by proning include ocular surface disease, acute angle closure, ischemic optic neuropathy, orbital compartment syndrome and vascular occlusions. CONCLUSIONS: COVID-19 patients may be more susceptible to ocular complications with increased proning practices and increasing demand on critical care staff. This review outlines these ocular complications with a focus on preventative and treatment measures to avoid devastating visual outcomes for the patient.