Case reports

Persian Gulf
Greenslade and Furnell 1988: 1 saltwater Catfish sting. Identification: not identified.

USA
McKinstry 1993: 1 Catfish sting. Identification: probably Noturus gyrinus. Literature review: 30 English-language reports of Catfish stings. Identification: Ictalurus catus 1/30, Noturus gyrinus 2/30, Noturus insignis 1/30, Galeichthys felis 1/30. Classification of all Catfishes that caused these accidents with the help of additional indirect criteria: freshwater Catfishes (e.g. Ictalurus sp.) 14/30, other small freshwater Catfishes (Noturus sp.), saltwater Catfishes (e.g. Galeichthys sp. and Bagre sp.) 10/30.

Signs & symptoms

Catfish venom contains venom components that can induce severe pain and cause local tissue necroses.

Local injury: puncture wounds. If the spine breaks off, parts of it may remain in the wound, as may other foreign matter, and, in addition to causing local toxic effects and bacterial infections, can lead to poor wound healing and extensive necroses.

Freshwater Catfishes, such as Ictalurus sp., can cause relatively deep wounds with nerve and tendon injuries, as they possess long spines. These may break off and can thus be a cause of poor wound healing. In contrast, small freshwater Catfishes, such as Noturus sp., have short spines. Thus, extensive tissue damage, aside from wound infections, caused by stings from these Catfishes are primarily due to local effects of the venom (McKinstry 1993).

Local effects

Local pain that can radiate to the trunk, local paraesthesias, local swelling, necroses (McKinstry 1993).

Wound infections: common.

Systemic signs and symptoms

Systemic effects are not well documented. The following have been reported: nausea, vomiting, diarrhoea, increased perspiration, confusion, loss of consciousness, cardiac arrhythmias, paralyses.

Morbidity

Wound infections, necroses, injury to nerves, vessels and tendons (McKinstry 1993).

Case fatality rate

1/30, this death was the result of a wound infection and sepsis (McKinstry 1993).

First aid

Immersion of the affected extremity in water as hot as can be tolerated, especially if it is not possible to get immediate medical assistance (water temperature approx. 45°C; temperature should be checked by a companion or with a healthy extremity in order to avoid burns; duration of treatment if necessary >30 min). Catfish venom, which, in addition to the physical injury, is responsible for pain and tissue destruction, is believed to be heat-labile. It is assumed that the hot water treatment may have an inactivating effect on the venom. However, this method is controversial, due to the risk of additional tissue damage. Its efficacy has not yet been documented in a controlled study.

Symptomatic treatment

Pain: injection of a local anaesthetic without the addition of a vasoconstrictor (lignocaine 1%) directly into and around the wound. Nerve block anaesthesia with lignocaine 1% or preferably bupivacaine because it has a longer duration of action (analogous to Fenner et al. 1989b, Dormon 1985).

Injury: wound cleaning and disinfection. X-ray to search for fragments of spine. Wound exploration in order to remove foreign matter (parts of the spine and spine sheath). Regular wound inspection and dressing changes until the wound has healed fully.

Tetanus prophylaxis. Antibiotic treatment if there is a clinically evident wound infection.