Can cornea be retrieved from poisoned donors? A focused narrative review

Corneal opacity due to various inflammatory and infectious conditions is a leading cause of blindness globally. In India, microbial keratitis and injuries to the eye are major contributors to corneal blindness. Corneal transplant is the only therapeutic option available for these patients. Despite the pressing need for corneal transplants, the donor to recipient ratio remains low in our country. Concurrently, the World Health Organization reports around 193,000 annual deaths from unintentional poisoning, and suicide claims over 700,000 lives annually, with pesticide self poisoning accounting for about 30% of suicides. Given this context, understanding the viability of corneal retrieval from poisoned donors is crucial. This narrative review aims to analyze the demographic and clinical data of poisoned patients from whom corneas were retrieved. Additionally, the study seeks to evaluate the feasibility and outcomes of corneal salvage in these cases. PubMed, Scopus, Web of Science, Google Scholar, and ProQuest were searched using the search string: (corneal donation OR corneal retrieval OR corneal transplant OR keratoplasty) AND (poisoned donors OR envenomation). Only English language studies that included real patient data were considered for inclusion, in accordance with the SANRA guidelines. The result of this narrative review shows that corneas are typically not retrieved from poisoned donors for transplant purposes due to the concerns about toxin transfer to the recipient, despite the cornea’s immune privileged status. A total of seven studies were included in the review (four case reports, one case series, two original research papers). The mean age of the donors was ≈ 41.08 years, the male: female ratio was 7.74:1, and the average success rate was 77.5%. The studies have shown successful corneal transplants from donors poisoned by substances like organophosphates, paraquat, cyanide, methanol, and snakebite venom. In conclusion, the evidence from existing studies suggests that corneas from poisoned donors can be safely utilized for transplantation without the risk of toxin transfer. Despite the systemic toxicity of various poisonous substances, corneal tissue frequently remains suitable for transplant purposes. However, further research is essential in the field of transplant toxicology to investigate the effects of different toxins on corneal tissue. Additionally, comparative studies examining the outcomes of transplants using corneas from poisoned versus non-poisoned donors are necessary to enhance our understanding of this issue.