Postmortem Ultrastructural Analysis of the Retina from COVID-19 Deceased Patients.

PURPOSE: COVID-19 (coronavirus disease 2019) is an infectious disease caused by SARS-CoV-2, first reported in 2019 in Wuhan, China. Among the common complications is a pro-inflammatory and hypercoagulative response that compromises the vasculature among various organs. METHODS: In this report, we present the postmortem retinal findings of five patients observed by means of optical microscopy and transmission and scanning electron microscopy techniques. RESULTS: Clinical manifestations such as retinal hemorrhages and exacerbated inflammatory infiltrate, altered ultra structure with swollen mitochondria and pyknotic cells in both layers of the retina were observed in all analyzed eyes. CONCLUSION: Our data point to the fragility of this tissue in cases of severe COVID-19.

Presumed SARS-CoV-2 Viral Particles in the Human Retina of Patients With COVID-19.

Importance: The presence of the SARS-CoV-2 virus in the retina of deceased patients with COVID-19 has been suggested through real-time reverse polymerase chain reaction and immunological methods to detect its main proteins. The eye has shown abnormalities associated with COVID-19 infection, and retinal changes were presumed to be associated with secondary microvascular and immunological changes. Objective: To demonstrate the presence of presumed SARS-CoV-2 viral particles and its relevant proteins in the eyes of patients with COVID-19. Design, Setting, and Participants: The retina from enucleated eyes of patients with confirmed COVID-19 infection were submitted to immunofluorescence and transmission electron microscopy processing at a hospital in São Paulo, Brazil, from June 23 to July 2, 2020. After obtaining written consent from the patients' families, enucleation was performed in patients deceased with confirmed SARS-CoV-2 infection. All patients were in the intensive care unit, received mechanical ventilation, and had severe pulmonary involvement by COVID-19. Main Outcomes and Measures: Presence of presumed SARS-CoV-2 viral particles by immunofluorescence and transmission electron microscopy processing. Results: Three patients who died of COVID-19 were analyzed. Two patients were men, and 1 was a woman. The age at death ranged from 69 to 78 years. Presumed S and N COVID-19 proteins were seen by immunofluorescence microscopy within endothelial cells close to the capillary flame and cells of the inner and the outer nuclear layers. At the perinuclear region of these cells, it was possible to observe by transmission electron microscopy double-membrane vacuoles that are consistent with the virus, presumably containing COVID-19 viral particles. Conclusions and Relevance: The present observations show presumed SARS-CoV-2 viral particles in various layers of the human retina, suggesting that they may be involved in some of the infection's ocular clinical manifestations.

COVID-19 Retinal Findings in Patients Admitted to Intensive Care Units and Wards.

The main purpose of this study was to investigate ocular clinical findings in patients with confirmed COVID-19 infection, of various levels of disease severity, who required mechanical ventilation and admission to intensive care units or specialized wards. Longitudinal, observational study conducted from March 2020 to June 2020. Color fundus and red-free photography were performed in both eyes following pupillary dilation. 104 participants were recruited from 2 different centers: 60 (58%) from the Hospital Municipal de Barueri intensive care unit (ICU) and 44 (42%) from specialized wards for patients with COVID-19 at the Hospital São Paulo. 21.9% presented with eye lesions, in 3% these lesions were vision compromising. Our results have shown similar rate of intraocular lesions in patients in both the ward or intensive care unit, regardless of medication use, including anticoagulant drugs.

Early use of nitazoxanide in mild COVID-19 disease: randomised, placebo-controlled trial.

BACKGROUND: Nitazoxanide is widely available and exerts broad-spectrum antiviral activity in vitro. However, there is no evidence of its impact on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. METHODS: In a multicentre, randomised, double-blind, placebo-controlled trial, adult patients presenting up to 3 days after onset of coronavirus disease 2019 (COVID-19) symptoms (dry cough, fever and/or fatigue) were enrolled. After confirmation of SARS-CoV-2 infection using reverse transcriptase PCR on a nasopharyngeal swab, patients were randomised 1:1 to receive either nitazoxanide (500 mg) or placebo, three times daily, for 5 days. The primary outcome was complete resolution of symptoms. Secondary outcomes were viral load, laboratory tests, serum biomarkers of inflammation and hospitalisation rate. Adverse events were also assessed. RESULTS: From June 8 to August 20, 2020, 1575 patients were screened. Of these, 392 (198 placebo, 194 nitazoxanide) were analysed. Median (interquartile range) time from symptom onset to first dose of study drug was 5 (4-5) days. At the 5-day study visit, symptom resolution did not differ between the nitazoxanide and placebo arms. Swabs collected were negative for SARS-CoV-2 in 29.9% of patients in the nitazoxanide arm versus 18.2% in the placebo arm (p=0.009). Viral load was reduced after nitazoxanide compared to placebo (p=0.006). The percentage viral load reduction from onset to end of therapy was higher with nitazoxanide (55%) than placebo (45%) (p=0.013). Other secondary outcomes were not significantly different. No serious adverse events were observed. CONCLUSIONS: In patients with mild COVID-19, symptom resolution did not differ between nitazoxanide and placebo groups after 5 days of therapy. However, early nitazoxanide therapy was safe and reduced viral load significantly.