A clinical metagenomic study of biopsies from Mexican endophthalmitis patients reveals the presence of complex bacterial communities and a diversity of resistance genes.

Infectious endophthalmitis is a severe ophthalmic emergency. This infection can be caused by bacteria and fungi. For efficient treatment, the administration of antimicrobial drugs to which the microbes are susceptible is essential. The aim of this study was to identify micro-organisms in biopsies of Mexican endophthalmitis patients using metagenomic next-generation sequencing and determine which antibiotic resistance genes were present in the biopsy samples. In this prospective case study, 19 endophthalmitis patients were recruited. Samples of vitreous or aqueous humour were extracted for DNA extraction for metagenomic next-generation sequencing. Analysis of the sequencing results revealed the presence of a wide variety of bacteria in the biopsies. Resistome analysis showed that homologues of antibiotic resistance genes were present in several biopsy samples. Genes possibly conferring resistance to ceftazidime and vancomycin were detected in addition to various genes encoding efflux pumps. Our findings contrast with the widespread opinion that only one or a few bacterial strains are present in the infected tissues of endophthalmitis patients. These diverse communities might host many of the resistance genes that were detected, which can further complicate the infections.

Pseudomelanoma diagnosis in a tertiary ophthalmologic centre in Spain.

BACKGROUND: The purpose of this study was to determine the types and frequency of lesions that can be misdiagnosed as choroidal or ciliary body melanomas (posterior uveal tract melanoma [PUM]). METHODS: This is a retrospective, descriptive study examining data from patients referred to Hospital La Paz in Madrid with the diagnosis of possible PUM between January 2005 and March 2020. All patients referred for PUM were studied. In collaboration with an oncology-specialized ophthalmologic centre, each patient underwent a full ophthalmic examination, ultrasonography, and optical coherence tomography, with agreed clinical criteria used to differentiate melanomas from pseudomelanomas. RESULTS: In our cohort of 715 patients, 48.9% had pseudomelanomas. Thirty-five different conditions were misdiagnosed as melanomas. The 5 most common conditions were choroidal nevus (40.5%), peripheral exudative hemorrhagic chorioretinopathy (12%), choroidal hemangioma (10.5%), choroidal metastasis (8%), and age-related macular degeneration (4%). CONCLUSIONS: Altering the diagnosis and changing the treatment and prognosis for patients can be difficult for a referral centre. Herein we present the largest European cohort investigated and highlight the importance of identifying the correct diagnosis to prevent mistreatment and possible overtreatment. These misdiagnoses can have an emotional effect on patients and their families, which could be avoided with a correct diagnosis. We analyze the most common pseudomelanoma diagnoses to help physicians better diagnose patients in their care.

Vision-related quality of life after surgery for vitreoretinal disorders in a Mexican population: an observational study.

Visual-related quality of life in retinal diseases has not been explored in the Mexican population, so the study aims to identify it in patients undergoing surgery due to advanced diabetic retinopathy, rhegmatogenous retinal detachment, and other causes of vitrectomy; the Visual Function Quality-25 questionnaire was applied to 76 patients, pre-and postoperative. It was divided into 10 domains and interpreted according to the National Eye Institute scores, where the highest value was the best visual function. Student's t-test for related samples and Wilcoxon's t-test were used to compare each domain between measurements, and Pearson's R test to correlate the total score of age and quality of life; a p value < 0.05 was considered significant. Diabetic retinopathy patients showed an improvement 1 and 3 months after surgery in all domains; in rhegmatogenous retinal detachment, there was an improvement observed up to 3 months, while a decrease in ocular pain was observed in other causes of vitrectomy. Differences found in all the quality-of-life scores were not statistical, but clinically significant. The study shows that visual-related quality of life domains improves after vitrectomy; the inclusion of this analysis might be considered relevant within the parameters of surgical success of the most prevalent vitreoretinal diseases.

Oxymetazoline: reduction of subconjunctival hemorrhage incidence after intravitreal injections.

OBJECTIVE: Subconjunctival hemorrhage (SCH) is an important minor side effect that might affect patient compliance to antivascular endothelial growth factor (anti-VEGF) intravitreal injection treatment (IVI). We sought to compare SCH incidence and pain score responses after topical oxymetazoline in naïve patients undergoing a single IVI of ranibizumab for diabetic macular edema. METHODS: Prospective, randomized, double-blinded, single centre study. One hundred two patients naïve to anti-VEGF were assigned to receive either topical oxymetazoline or placebo 30 minutes before IVI. SCH incidence and area were measured by slit lamp 24 hours after, and pain was evaluated 5 minutes and 24 hours after. RESULTS: SCH incidence was reported on 72% in control group versus 51% in oxymetazoline group (p = 0.037). Mean size of SCH was 16.82 mm2 in control group versus 12.55 mm2 in oxymetazoline group (p = 0.394). Prevalence of local pain in the overall study population was 60%. No significant statistical difference was achieved between groups 5 minutes or 24 hours after IVI in either pain scale evaluation. CONCLUSION: Administration of topical oxymetazoline 30 minutes before IVI is a single, harmless, cost-effective intervention that decreases the incidence of subconjunctival hemorrhage. This may considerably improve patient treatment satisfaction and promote compliance to IVI therapy.