Corneal transplant rejection. Credit: Johan Boonstra

US researchers have reported four cases or corneal transplant rejection in patients following their Covid-19 vaccinations.

Led by Dr Amar Shah, from the Bascom Palmer Eye Institute at the University of Miami Miller School of Medicine, the study team said each patient had received a different type of transplant. One had Descemet membrane endothelial keratoplasty six months prior to their vaccination, one had penetrating keratoplasty three years previously, one had Descemet stripping automated endothelial keratoplasty and the fourth had a penetrating keratoplasty graft. However, all four experienced endothelial graft rejection within nine days to three weeks after their first or second dose of mRNA-1273 (Moderna) vaccine, said researchers.

The patients were treated with frequent topical corticosteroids, resulting in improvements for three patients and complete resolution in the fourth. Further studies are needed to elucidate the causal mechanism of corneal graft rejection after Covid-19 vaccination, concluded the researchers in Cornea.