Stonefish

Appearance

Reef stonefish have an overall body length of approximately 40 cm and are difficult to see, as they blend　in with rocks on the seabed. Their spines are tough and able to penetrate rubber-soled boots and wetsuits.

Epidemiology

Stonefish stings, including those from reef stonefish, are a common injury seen in the emergency room. They are primarily found in the coastal waters of the Indo-Pacific region, including the USA, Australia, Malaysia, Hong Kong, and Singapore. Few Japanese studies of stonefish envenomation have been reported; however, Hifumi et al. recently reported 15 cases over a 5-year observation period and two deaths related to stonefish envenomation have been reported in Japan.

Venom activity and clinical symptoms

Fatalities resulting from reef stonefish stings have been reported in Okinawa prefecture. These injuries may have been sustained by individuals fishing for food, since stonefish are eaten in some regions. Venom from the genus Synanceia has hyaluronidase activity and causes hemolysis, hypotension, and nerve paralysis.

Diagnosis

Currently, there are no definitive diagnostic criteria for stonefish envenomation. The diagnosis of stonefish envenomation is based on the patient’s history or the positive identification of the stonefish presented by the patient.

Treatment

It is important to warm the site of stonefish stings as this helps to relieve pain. Warming the affected area to approximately 43 °C is recommended. Antivenom is available and consists of the purified F(ab)2 fragment of equine IgG antibodies raised against the venom of Synanceia trachynis. In a study conducted in Hong Kong, 25% of patients received treatment with antivenom.

Prevention

Use thick rubber-soled footwear to prevent spine penetration.

References
Hifumi T, et al. SN Comprehensive Clinical Medicine (2020) 2:2288–2292

Blog 2020.09.05 Review of marine organism bite wounds (including serum therapy) was created.