Envenoming by the rough-scaled snake (Tropidechis carinatus): a series of confirmed cases.

OBJECTIVE

To describe demographic, geographical and clinical features of envenoming by the rough-scaled snake (RSS) (Tropidechis carinatus).

DESIGN, SETTING AND PARTICIPANTS: Prospective cohort study of RSS snakebite victims, recruited between January 2004 and December 2008, as part of the Australian Snakebite Project. RSS envenoming cases were confirmed by snake identification and/or venom-specific enzyme immunoassay.

MAIN OUTCOME MEASURES

Clinical and laboratory features of envenoming.

RESULTS

There were 24 confirmed cases of RSS envenoming, nearly all occurring in coastal areas between northern New South Wales and south-eastern Queensland. Twenty-three patients had local bite-site effects and 17 had at least three non-specific systemic effects (eg, nausea, headache). All 24 had venom-induced consumption coagulopathy (VICC), and 19 had an international normalised ratio>3.0. Six had bleeding from the bite site or intravenous cannula site, 10 had blood detected on urinalysis, and one had a major intra-abdominal haemorrhage. Mild neurotoxicity developed in two patients, and one patient developed myotoxicity with generalised myalgia, myoglobinuria and a peak creatine kinase level of 59 700 IU/L. Twenty-three patients were treated with antivenom (21 with tiger snake antivenom, two with polyvalent antivenom). Free venom was undetectable in 19 of 20 blood samples taken after antivenom administration.

CONCLUSION

RSS envenoming occurs predominantly in coastal areas of northern NSW and southern Queensland, and within this range, most envenoming is due to the RSS rather than tiger snakes. Clinically it is characterised by VICC, with mild neurotoxicity and myotoxicity in some cases. Tiger snake antivenom appears to be effective against RSS envenoming.