Absence of Severe Acute Respiratory Syndrome-Coronavirus-2 RNA in Human Corneal Tissues

Bayyoud, Tarek; Iftner, Angelika; Iftner, Thomas; Bartz-Schmidt, Karl Ulrich; Rohrbach, Jens Martin; Ueffing, Marius; Schindler, Michael; Thaler, Sebastian

To examine corneal tissue for severe acute respiratory syndrome–coronavirus 2 (SARS-CoV-2) positivity regarding implications for tissue procurement, processing, corneal transplantation, and ocular surgery on healthy patients. We performed quantitative reverse transcription-polymerase chain reaction qRT-PCR-testing for SARS-CoV-2 RNA on corneal stroma and endothelium, bulbar conjunctiva, conjunctival fluid swabs, anterior chamber fluid, and corneal epithelium of coronavirus disease 2019 (COVID-19) postmortem donors. METHODS: Included in this study were 10 bulbi of 5 COVID-19 patients who died because of respiratory insufficiency. Informed consent and institutional review board approval was obtained before this study (241/2020BO2). SARS-CoV-2 was detected by using a pharyngeal swab and bronchoalveolar lavage. Tissue procurement and tissue preparation were performed with personal protective equipment (PPE) and the necessary protective measures. qRT-PCR-testing was performed for each of the abovementioned tissues and intraocular fluids. RESULTS: The qRT-PCRs yielded no viral RNA in the following ocular tissues and intraocular fluid: corneal stroma and endothelium, bulbar-limbal conjunctiva, conjunctival fluid swabs, anterior chamber fluid, and corneal epithelium. CONCLUSIONS: In this study, no SARS-CoV-2-RNA was detected in conjunctiva, anterior chamber fluid, and corneal tissues (endothelium, stroma, and epithelium) of COVID-19 donors. This implicates that the risk for SARS-CoV-2 infection using corneal or conjunctival tissue is very low. However, further studies on a higher number of COVID-19 patients are necessary to confirm these results. This might be of high importance for donor tissue procurement, processing, and corneal transplantation.