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Conjunctival Swabs Reveal Higher Detection Rate Compared to Schirmer Strips for SARS-CoV-2 RNA Detection in Tears of Hospitalized COVID-19 Patients.

TitleConjunctival Swabs Reveal Higher Detection Rate Compared to Schirmer Strips for SARS-CoV-2 RNA Detection in Tears of Hospitalized COVID-19 Patients.
Publication TypeJournal Article
Year of Publication2022
AuthorsSabage, Luís Expedito, Sun Young Joo, Wolf Julian, Sabage Josmar, Mazzo Alessandra, Santos Carlos Ferreira, Mahajan Vinit B., and Lourençone Luiz Fernando M.
JournalJ Clin Med
Date Published2022 Nov 24

Purpose: To determine the prevalence of SARS-CoV-2 in tear samples and to investigate whether it correlates with ocular findings and patients’ prognosis in Brazil. Methods: Tears were collected using Schirmer strips (SS) and conjunctival swabs (CS) from patients hospitalized with laboratory-confirmed SARS-CoV-2 infection. Samples were analyzed using qRT-PCR. Demographic and clinical data, ocular symptoms, and Schirmer tests (ST) were collected from patients. Charlson Comorbidity Index (CCI) was used to rate comorbidities, and patients were monitored until hospital discharge or death. Results: There were 61 hospitalized patients, 33 of which were diagnosed with COVID-19. Within the confirmed COVID-19 patients, SARS-CoV-2 was detected in 18.2% (n = 6) of CS and 12.1% (n = 4) of SS samples. Subjective and objective parameters for dry eye syndrome (e.g., ST COVID-19: 8.3 ± 6.4mm, non-COVID-19: 8.9 ± 6.6mm, p > 0.05) were comparable between COVID-19 (n = 33) and non-COVID-19 patients (n = 28). Among the 16 COVID-19 patients exhibiting ocular symptoms, only tearing was reported significantly more frequently when tear samples were positive for SARS-CoV-2 (p < 0.05). Strikingly, patients whose tears tested positive for SARS-CoV-2 had significantly inferior CCI (pos.: 34.0 ± 31.8%, neg.: 67.6 ± 36.4%, p < 0.05) and higher mortality rates (pos.: 50.0%, neg.: 7.4%, p < 0.01). Conclusions: SARS-CoV-2 was detected with a prevalence of 18.2% on the ocular surface. Decreased CCI and increased mortality rate in the positive tear group suggests that viral detection may relate to prognosis and highlight the need of personal protective measures for healthcare professionals. Most of the patients, regardless of COVID-19 diagnosis, had low tear production and eye discomfort, possibly pointing to the need for artificial tear use during hospitalization.

Alternate JournalJ Clin Med
PubMed ID36498504
PubMed Central IDPMC9737489
Grant List2020/07365-8 / / São Paulo Research Foundation /
2022/01956-0 / / São Paulo Research Foundation /
R01EY031952 / NH / NIH HHS / United States
R01EY030151 / NH / NIH HHS / United States
R01EY024665 / NH / NIH HHS / United States
R01EY025225 / NH / NIH HHS / United States
P30EY026877 / NH / NIH HHS / United States
/ / Stanford ChEM-H IMA /
/ / Stanford Center for Optic Disc Drusen /
/ / Research to Prevent Blindness, New York /
/ / BrightFocus Foundation's Macular Degeneration Research Program /
CAPES - Finance Code 001 / / Coordination for the Improvement of Higher Education Personnel /