conjunctival polymerase chain reactions in covid-19 patients and its correlation with clinical and paraclinical indexes

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.