Conjunctival testing for SARS-CoV-2 is not valuable for patients presenting with acute conjunctivitis who are not experiencing respiratory distress, according to research published in Clinical Ophthalmology.
Researchers sought to determine the prevalence of SARS-CoV-2 associated conjunctivitis among patients with suspected viral conjunctivitis, but no respiratory symptoms. They enrolled 36 adult patients in the study after screening them for COVID-19. They excluded patients with respiratory symptoms indicating COVID-19 or red-eye symptoms attributed to other causes besides conjunctivitis. Patients self-reported their medical history and underwent slit-lamp examination and external ocular photography. The researchers completed conjunctival, nasal, and nasopharyngeal swabs.
Redness was the most common eye symptom among participants (97%). Other symptoms included swelling, tearing, irritation, crusting, and itching (81%, 78%, 78%, 64%, and 58%, respectively), with 14 patients presenting with binocular symptoms at baseline.
The researchers did not detect SARS-CoV-2 RNA (95% CI: 0 to 0.08) in any of the nasopharyngeal or nasal samples (33 nasal, 23 nasopharyngeal). Among the 25 patients who responded to follow-up calls, the mean duration of conjunctival symptoms lasted 15.1 ± 8.9 days.
Overall, 9 of 25 patients tested positive for conjunctival adenovirus, 14 reported seasonal allergies (52%), 5 had bilateral conjunctivitis, and 5 developed systemic symptoms possibly associated with COVID-19, such as headache, cough, and muscle ache. No patients were diagnosed with COVID-19 during the 2 week follow up.
“Our study demonstrated that SARS-CoV-2 associated conjunctivitis was uncommon in the absence of COVID-19 even during the peak of the pandemic,” according to investigators. “We suggest that routine conjunctival testing is not valuable in patients with acute conjunctivitis in the absence of respiratory symptoms suggesting COVID-19.”
Limitations of the study included small sample size, selection bias, and changes in COVID-19 strain dominance during the pandemic.
Karakus S, Foster J, Dai X, et al. Prevalence of SARS-CoV-2 in conjunctival swab samples among patients presenting with conjunctivitis during the COVID-19 pandemic. Clin Ophthalmol. 2022:16;127-133. doi:10.2147/OPTH.S343793