Iatrogenic thermal burn after hot water immersion for weever fish sting treatment: a case report

Lesser weever fish are saltwater fish that are found on the Mediterranean and European coasts, over sandy and muddy seabed areas, typically around the summer season. These bottom dwellers have envenoming dorsal spines that sting when stepped on. Severe pain is the main symptom. Initial treatment involves wound irrigation, removal of spines if they are visible and immediate hot water immersion (HWI). Tetanus prophylaxis, leg elevation and analgesia are recommended after pain subsides. HWI treatment is described as immersion of the affected area in hot, but not scalding, water to tolerance (upper limit 45 °C) for 30-90 min or until there is significant pain relief. While HWI is an effective therapy for the pain control of marine envenomation, it presents a potential risk of thermal burn injury in the untrained or unsupervised. Here, we present a case of an iatrogenic thermal burn after HWI for the treatment of a weever fish sting.

A 16-year-old girl was referred to our outpatient department with a superficial dermal thickness burn to her big toe 12 days after accidental stepping on a lesser weever fish. She reported receiving HWI treatment at the scene of the injury. She was treated with dressing, oral antibiotics and leg elevation. This healed with no sequalae at nine-month follow-up.

Thermal burn injury can occur after HWI treatment. Providers should be aware and diligent while the patient needs to be educated in the potential risks.

Stings from lesser weever fish occur mostly in the summer months. These bottom dweller saltwater fish are found in the Mediterranean and European coasts, over sandy and muddy seabed areas; it releases venom from its dorsal spine when stepped on. Severe pain is the main symptom. Recommended first aid includes wound irrigation, removal of spines if they are visible and immediate hot water immersion (HWI) treatment. HWI means immersion of the affected part into hot, but not scalding, water (upper limit 45 °C) for 30-90 min or until pain is alleviated. In an ideal situation, the water temperature should be checked with a thermometer. However, in practice, where no thermometer is available, the water must be tested before immersion. It is advised to ensure that the water should be no hotter than the first aider can stand or the highest temperature tolerable by the patient. However, HWI treatment has a potential risk of burn injury. Here we describe a case of a 16-year-old patient who sustained burn injury after HWI therapy received after a sting by a weever fish. The patient was treated with dressings and the wound healed without requiring surgical intervention. Here, we like to highlight that although HWI is effective in treating stings from marine animals, both the provider and the patient need to be aware of potential burn injury associated with this treatment.