The family Scorpaenidae are saltwater fish that are mostly bottom dwellers noted for their ability to camouflage themselves and disappear into the environment. There are 30 genera and about 300 species, some 30 of which can envenomate humans. Although they once were considered an occupational hazard only to commercial fishing, increasing contact with these fish by scuba divers and home aquarists has increased the frequency of envenomations. In addition, due to changing water temperatures and introduction of exotic species, some of these fish can now be found in aquatic environments where they previously weren't present, such as the recent proliferation of lionfish in the Gulf of Mexico.
Envenomation usually occurs when the fish is being handled or stepped on or when the aquarist has hands in the tank. The dorsal, anal, and pectoral fins are supported by spines that are connected to venom glands. The fish will erect its spines and jab the victim, causing release of venom (and often sloughing of the integumentary sheath of the spine into the wound). The venom of all these organisms is a heat-labile mixture that is not completely characterized.
The dose of venom involved in any sting is variable. Interspecies difference in the severity of envenomation is generally the result of the relation between the venom gland and the spines.
Synanceja (Australian stonefish) have short, strong spines with the venom gland located near the tip; therefore, large doses of venom can be delivered, and severe envenomation can result.
Pterois (lionfish, turkeyfish) have long delicate spines with poorly developed venom glands near the base of the spine and therefore are usually capable of delivering only small doses of venom.
Envenomation typically produces immediate onset of sharp, throbbing, intense, excruciating pain. In untreated cases, the intensity of pain peaks at 60–90 minutes, and the pain may persist for 1–2 days.
Systemic intoxication associated mainly with stonefish envenomation can include the rapid onset of hypotension, tachycardia, cardiac arrhythmias, myocardial ischemia, syncope, diaphoresis, nausea, vomiting, abdominal cramping, dyspnea, pulmonary edema, cyanosis, headache, muscular weakness, and spasticity.
Local tissue effects include erythema, ecchymosis, and swelling. Infection may occur owing to retained portions of the integumentary sheath. Hyperalgesia, anesthesia, or paresthesias of the affected extremity may occur, and persistent neuropathy has been reported.
Usually is based on a history of exposure, and the severity of envenomation is usually readily apparent.
Specific levels. There are no specific toxin levels available.
Other useful laboratory studies for severe intoxication include electrolytes, glucose, BUN, creatinine, creatine kinase (CK), urinalysis, ECG monitoring, and chest radiography. Soft-tissue radiographs of the sting site may occasionally demonstrate a retained integumentary sheath or other foreign material but should not be ...