A Case Study of Lionfish Sting-Induced Paralysis

The lionfish, Pterois volitans (Linnaeus, 1758), a venomous scorpionfish, has gained popularity among aquarium owners and has recently become established along the Southeast US, Caribbean, and Gulf of Mexico. The primary clinical effect due to envenomation is local pain, with systemic symptoms being a rare finding. Herein is reported a rare envenomation case of a 24 year old male who presented to the Emergency Department two hours following a lionfish sting to his right hand. Within three hours of envenomation he developed paralysis of all extremities. Additional symptoms included hypertension, tachycardia, and numbness of both hands. Respiratory function and range of motion of his head and neck remained intact. Hot water immersion of the affected extremity was initiated and continued throughout most of his Intensive Care Unit stay. By eight hours post-envenomation resolution of all paralysis occurred. Lionfish envenomations are typically a pain control issue and usually respond well to hot water immersion. In vitro, lionfish venom has been demonstrated to increase intracellular calcium with resulting sustained muscle contraction. Additionally, muscle fibrillation has been shown to be induced by the release of acetylcholine followed by acetylcholine depletion and loss of muscle responsiveness. These effects may explain the observed neuromuscular weakness in this patient. Lionfish envenomation has the potential to cause profound neuromuscular weakness. Treatment with hot water immersion, wound care, and good supportive measures are generally all that is required to ensure a favorable outcome. Divers and fishers should exercise caution when handling or interacting with lionfish given the potential for systematic effects from envenomation.