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American Journal of Transplantation ; 22(Supplement 3):638-639, 2022.
Article in English | EMBASE | ID: covidwho-2063546


Purpose: Solid organ transplant recipients (SOTR) develop weak antibody responses after SARS-CoV-2 vaccination. Published data on neutralizing activity of plasma, a better measure of protection, in SOTR following an additional dose of SARSCoV- 2 vaccine is limited. Method(s): Plasma was longitudinally collected from SOTR following initial COVID- 19 vaccination. Neutralizing activity against SARS-CoV-2 was assessed using the cPass Neutralization Antibody Detection Kit (GenScript, Biotech). ELISAs were performed against SARS-CoV-2 proteins (S1, N, RBD), CMV (glycoprotein B), Influenza A H1N1 (nucleoprotein), HSV-1, EBV glycoprotein (gp350), and tetanus toxoid for comparison. Result(s): Demographic and clinical characteristics are summarized in table 1. No participants had evidence of COVID-19 infection as IgG titers to SARS-CoV-2 N protein were low. Neutralizing activity against SARS-CoV-2 RBD was observed in 39.6% of individuals (N=21/53) ~93 days after initial vaccination. Participants with neutralizing activity were more likely to have received a liver transplant (47.6% vs 6.25%, p=0.001), and less likely to be on an anti-metabolite (52.4% vs. 87.5%, p=0.009) or triple immunosuppression (14.3% vs. 53.1%, p=0.008). After an additional vaccine dose, 78.1% (N=25/32) of participants developed neutralizing activity with significant increases in viral neutralization (figure 1, median 36.8% [95%CI 18.9-64.6] to 97.2% [95%CI 74.0-98.9], p<0.0001). Participants with low neutralizing activity demonstrated adequate antibody titers to other microbial antigens (figure 2). Conclusion(s): An additional dose of SARS-CoV-2 vaccine increased the number of SOTR with neutralizing activity and the magnitude of the seroresponse. SOTR with low neutralizing activity maintain humoral responses to other microbial antigens suggesting the diminished seroresponse might be related to inhibition of new B cell responses.

Investigative Ophthalmology and Visual Science ; 62(8), 2021.
Article in English | EMBASE | ID: covidwho-1378868


Purpose : The Centers for Disease Control reports 28.2% of surveyed US adults had reduced access to medical care (June/August 2020) due to the COVID-19 pandemic, with 8.9% reporting reduced access to vision care. A non-mydriatic digital retinal camera was piloted for deployment to the Emergency Department (ED) to help address this gap in vision care. Referrals for clinical follow-up in vision threatening diseases (VTDs) such as age-related macular degeneration, cataracts, diabetic retinopathy (DR), and glaucoma were assessed with human readers. Artificial Intelligence (AI) deep learning software was evaluated in known DR cases. Methods : 33 patients with known VTDs (48.48% male, avg 59.33 years) and 36 control subjects (41.67% male, avg 31.33 years) were included in tele-ophthalmology screening. A Canon CR-2 Plus AF non-mydriatic retinal camera captured 45-degree angle color and auto-fluorescence images of the eyes. Images (136 eyes) were graded by a certified telemedicine reader on site and an off-site clinical ophthalmologist following International Clinical Diabetic Retinopathy Disease Severity Scale (ICDRSS). Intergrader agreement between readers was evaluated with Cohen's kappa. An automated deep learning screening software optimized for DR (SELENA+, EyRIS Pte Ltd, Singapore) performed independent validation of readable color fundus images (17 eyes). Results : 5.07% of images were deemed unreadable by graders due to poor quality. Intergrader agreement for subject referral was κ = 0.710 (95% CI 0.545-0.875, p<.0005), with the clinical ophthalmologist generating more referrals than the telemedicine reader. Readers had 96.97% sensitivity (95% CI 91.12-1.028) and 72.22% specificity (95% CI 57.59- 86.85) in detecting referable disease. Positive predictive value was 76.19% (CI 63.31%- 89.07%) and negative predictive value was 96.30% (CI 89.17%- 1.034%). Of the 10 false positives, 6 were referred for rule out of glaucoma. Four had early stage cataracts that were deemed nonurgent. SELENA+ referred 100% of the known 9 DR patients. Conclusions : Tele-ophthalmology deployment in the ED helps limit patient and staff exposure to SARS-CoV-2 without sacrificing evaluation for VTDs. Tele-ophthalmology readers err on the side of caution to avoid missing VTD in a given patient. Use of AI can help keep strict adherence to referral guidelines.