Corneal Endothelial Cell Damage Following Bee Stings: A Report of Two Cases

Corneal bee stings cause inflammation through direct venom toxicity and type I hypersensitivity reactions that can lead to endothelial cell damage. In severe cases, these injuries can progress to bullous keratopathy, a condition that necessitates corneal transplantation. Here, we reported two cases in which transparent healing was achieved through steroid treatment, yet subsequent corneal endothelial cell damage ensued. In the initial case, an 81-year-old male sustained a sting in the left eye from a honeybee. Initial visual acuity was 20/17 in the right eye and 20/33 in the left eye. A preliminary evaluation of the patient's eye revealed the presence of corneal epithelial damage, Descemet's membrane folds, and corneal edema measuring approximately 2 mm in the inferonasal peripheral cornea. Following treatment with topical steroids and oral betamethasone from day one, the cornea exhibited a transparent healing response with visual acuity improving to 20/33 in the affected eye. However, a significant decrease in endothelial cell density was observed, measuring at 1,306 cells/mm² in the affected eye, compared to the normal density of 2,677 cells/mm² in the contralateral eye. In the second case, a 49-year-old male with a history of laser-assisted in situ keratomileusis surgery was stung in the right eye by a paper wasp (<i>Polistes</i>). Initial visual acuity was 20/40 in the right eye and 20/13 in the left eye. A preliminary evaluation revealed the presence of a corneal epithelial defect measuring approximately 3 mm in diameter in the superior cornea, Descemet's membrane folds, corneal edema extending across the entire cornea, and posterior corneal deposits. Following treatment with topical and systemic steroids, a state of transparent healing was achieved with final visual acuity of 20/20 in the affected eye; however, endothelial cell density was significantly reduced to 1,243 cells/mm² in the affected eye compared to 2,213 cells/mm² in the unaffected eye. Contact specular microscopy revealed a particularly severe reduction at the sting site (1,151 cells/mm²) compared to the peripheral area (3,212 cells/mm²). The administration of steroids, both locally and systemically, has been demonstrated to be an effective treatment for corneal bee stings. Notwithstanding the efficacy of transparent healing, there is the possibility of a decrease in corneal endothelial cell density. The findings of this study indicate the necessity of meticulous follow-up procedures, even in cases that are initially treated with a conservative approach.