Key Genes of Immunity Associated with Pterygium and Primary Sjögren's Syndrome.

Pterygium and primary Sjögren's Syndrome (pSS) share many similarities in clinical symptoms and ocular pathophysiological changes, but their etiology is unclear. To identify the potential genes and pathways related to immunity, two published datasets, GSE2513 containing pterygium information and GSE176510 containing pSS information, were selected from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) of pterygium or pSS patients compared with healthy control conjunctiva, and the common DEGs between them were analyzed. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were conducted for common DEGs. The protein-protein interaction (PPI) network was constructed using the STRING database to find the hub genes, which were verified in clinical samples. There were 14 co-upregulated DEGs. The GO and KEGG analyses showed that these common DEGs were enriched in pathways correlated with virus infection, antigen processing and presentation, nuclear factor-kappa B (NF-κB) and Th17 cell differentiation. The hub genes (IL1R1, ICAM1, IRAK1, S100A9, and S100A8) were selected by PPI construction. In the era of the COVID-19 epidemic, the relationship between virus infection, vaccination, and the incidence of pSS and pterygium growth deserves more attention.

Impact of COVID-19 on ophthalmic surgery in Australia

Purpose : The effect of coronavirus disease 2019 (COVID-19) on ophthalmic surgical case numbers in Australia and globally remains poorly characterised. Increased incidence of COVID-19 in Australia between March and April 2020 led to a national lockdown and elective surgery restrictions. The aim of this population-based study was to quantify the early impact of COVID-19 on ophthalmic surgery in Australia, comparing surgical service rates in 2019 and 2020. Methods : Retrospective analysis of the number of ophthalmic surgical services in 2019 and 2020 in all Australian States and Territories, as recorded by Medicare (Australian Government-funded universal health insurance scheme subsidising healthcare costs for Australian residents). Monthly surgical service rates were calculated and Poisson regression was used to compare the change in service rates between months. Results : Between March and April 2020, surgical service rates decreased for: cataract surgery (by 71%, 95% CI: 70-72%), cataract surgery with minimally invasive glaucoma surgical device insertion (by 71%, 95% CI: 65-75%), pterygium removal (by 67%, 95% CI: 60- 72%), corneal transplantation (by 31%, 95% CI: 9-48%), and collagen crosslinking for corneal ectasias (by 35%, 95% CI: 18-48%). Comparatively, service rates for these surgeries did not differ or decreased less between March and April 2019. Interestingly, glaucoma filtration surgery rates decreased between March and April in 2020 (by 44%, 95% CI: 29- 56%) and also in 2019 (by 45%, 95% CI: 31-55%), whilst retinal detachment surgery rates were unchanged between these months in 2020 (crude decrease 9%, 95% CI: -28 to 16%) and 2019 (crude decrease 11%, 95% CI: -26 to 9%). Conclusions : Despite relatively low rates of COVID-19 community transmission in Australia in 2020, ophthalmic surgical service rates decreased during months in lockdown and with restrictions, largely for non-time-critical conditions. These data may have health planning implications as the pandemic continues, with future lockdowns and restrictions possible, especially as COVID-19 variants emerge.

Trends in California ophthalmology surgical volume during the COVID pandemic

Purpose : Pandemic era restrictions on non-essential travel, redistribution of healthcare resources, and nursing shortages have impacted the ability of ophthalmologists to deliver care. California had among the strictest 2020 restrictions during the pandemic with reallocation of non-essential surgical resources. This study assesses changes in surgical volume of common ophthalmic procedures in California since the COVID-pandemic. Methods : The California Health and Human Services Agency (Office of Statewide Health Planning & Development) maintains ambulatory and emergency room procedural databases. Common ophthalmic procedures and surgical volumes were extracted for 29 CPT codes from 2014-2020. Procedures with fewer than 100 cases were excluded. Results : Overall, ophthalmology surgical volume decreased by 19% from 2019 to 2020. Greatest declines were for anterior lamellar corneal transplant (39%) and pterygium with graft (38%). Simple cataract surgeries declined by 29% in 2020, compared to an average annual decline of 3% from 2014-2019. Volume increased only for two surgeries: aqueous shunt with graft (2%) and complex retinal detachment (0.2%). Temporal artery biopsies, historically stable with 0.2% average change from 2014-2019, declined by 28% in 2020. Retinal detachment repairs declined by 20% and 17% (with and without vitrectomy, respectively). In comparison, laparoscopic appendectomy only declined by 2% in 2020. Limitations of this study include role of population changes and changes in annual coding practices. Conclusions : COVID era declines were noted across almost all ophthalmic surgeries with steep drops in perceived non-urgent procedures such as pterygium and cataract. However, delays in cataracts and other conditions can result in increased disease burden and morbidity for patients. Uniquely, tube shunt procedures increased, perhaps due to progression of glaucoma from delayed routine care. For vision-preserving surgeries such as retinal detachment repair, lack of accessible care during the pandemic is especially concerning.

Hydroxychloroquine treatment on SARS-CoV-2 receptor ACE2, TMPRSS2 and NRP1 expression in human primary pterygium and conjunctival cells.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the pathogen for coronavirus disease 2019 (COVID-19) pandemic. Its infection depends on the binding of spike protein to the host cell receptor angiotensin-converting enzyme 2 (ACE2), type II transmembrane serine protease (TMPRSS2) and neuropilin-1 (NRP1). Hydroxychloroquine has been applied as one of the COVID-19 treatment strategies. Here we aimed to evaluate hydroxychloroquine treatment on SARS-CoV-2 receptor expression in human primary pterygium and conjunctival cells and its potential influences. Expression of ACE2, TMPRSS2 and NRP1 proteins were found in the epithelial layer of both primary pterygium and conjunctiva tissues as well as in their isolated fibroblasts. High concentration of hydroxychloroquine treatment significantly reduced the viability of both primary pterygium and conjunctival cells. ACE2 protein expression was significantly decreased in both pterygium and conjunctival cells after hydroxychloroquine treatment. Hydroxychloroquine also reduced NRP1 protein expression in conjunctival cells. In contrast, TMPRSS2 protein expression showed slightly increased in conjunctival cells. Notably, ROS production and SOD2 expression was significantly elevated in both pterygium and conjunctival cells after hydroxychloroquine treatment. In summary, this study revealed the reduction of ACE2 and NRP1 expression by hydroxychloroquine in human primary pterygium and conjunctival fibroblasts; yet with the increase in TMPRSS2 expression and oxidative stress and decrease in cell viability. Implementation of hydroxychloroquine for COVID-19 treatment should be carefully considered with its potential side effects and in combination with TMPRSS2 inhibitor.