Corneal Toxicity After Exposure to Aquarium Coral Palytoxin
American Journal of Ophthalmology, February 2017
Farooq et al. conducted a multicenter retrospective analysis of 7 cases of corneal toxicity that occurred shortly after presumed exposure to palytoxin from zoanthid coral. Palytoxin is a non-proteinaceous compound that acts as a vasoconstrictor and inhibitor of sodium-potassium ATPase pumps. The authors found that the effects of corneal exposure to palytoxin vary from mild to severe and can be progressive.
At clinical presentation, all 7 patients (10 affected eyes) reported recent contact with zoanthid coral in aquarium water. Exposure to palytoxin was inferred from the patients’ history; the toxin was not isolated from ocular samples. Corneal conditions ranged from superficial punctate epitheliopathy to bilateral corneal melt and eventual perforation. No patient had histologic evidence of ocular infection. A paracentral ring infiltrate developed in the cornea of 1 patient. Acute and chronic keratitis was observed near the ulcer of a patient with corneal perforation; few inflammatory cells were found despite the presence of severe stromal keratolysis.
Mild corneal toxicities resolved after treatment with topical corticosteroids, lubrication, and antibiotic prophylaxis. More severe corneal cases required topical/oral steroids, topical/oral antibiotics, serum tears, and/or amniotic membrane. Two patients (3 eyes) experienced decreased vision and were fitted with contact lenses. Three other patients (4 eyes) underwent penetrating keratoplasty. Most patients had been unaware of their potential for palytoxin exposure.
Although many investigators have described systemic outcomes of palytoxin exposure, few have addressed the ocular effects. In this largest case series of the corneal effects of palytoxin, the authors concluded that a careful history, timely treatment, and frequent monitoring are crucial for patients who present with possible corneal exposure to this toxin. They also recommended that aquarists use protective goggles and gloves. Further, they noted that a national reporting system for this toxic exposure would be beneficial and that awareness of this danger should be heightened among eye care professionals, aquarium enthusiasts, and the general public.
The original article can be found here.