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Conjunctival polymerase chain reactions in COVID-19 patients and its correlation with clinical and paraclinical
Maral Farzin1, Seyed Ahmad Rasoulinejad2, Mansour Babaei3
1Department of Medicine, School of Medicine, Babol University of Medical Sciences, Babol, Iran.
Background And Objectives:
This study aimed to detect SARS-CoV-2 in conjunctival samples of COVID-19 patients to investigate the transmission route of COVID-19 and its correlation with laboratory indexes.
Materials And Methods:
In this cross-sectional study, 44 COVID-19 patients were tested for conjunctival PCR in Ayatollah Rouhani hospital of Babol, Iran, in January and February 2021. The conjunctival samples were collected using a conjunctival swab and suspended in a viral transport medium. After RNA extraction and cDNA synthesis, real-time PCR was performed to investigate the SARS-CoV-2 genome in samples. The ocular manifestations and laboratory indexes were evaluated for all patients.
Results:
Among 44 COVID-19 patients, 6 samples (13.63%) were positive in terms of conjunctival PCR. The mean ± SD age of conjunctival PCR-positive patients was 76.17 ± 16.61-year-old, while conjunctival PCR-negative COVID-19 patients were aged 57.54 ± 13.61-year-old (p <0.05). D-dimer serum level is significantly higher in conjunctival PCR-positive COVID-19 patients (4001.00 ± 3043.36 μg/ml) compared to normal individuals (496.80 ± 805.92 μg/ml, p <0.01).
Conclusion:
Our study showed that the conjunctiva and tear contain the SARS-CoV-2 in COVID-19 patients as a possible transmission route.
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