Snake bite fatality in the Northern Territory: diagnostic challenges and lessons learnt at autopsy

Snakebites are an important cause of morbidity in the Northern Territory and envenomation has to be considered by the forensic pathologist when investigating cases of sudden death. We discuss the case of an adult female with no medical history who was fully alert but then suddenly collapsed and demised within 30 minutes. There were unsubstantiated reports of a snake bite in the prior half hour. Urine and blood were tested for snake venom but were negative. Initial external examination identified no visible bite marks. Renewed efforts to get corroborating information revealed that a snake had been seen in the vicinity of the deceased. Examination with a magnifying glass and dissecting microscope identified two puncture marks on the left ankle. The skin and underlying subcutaneous tissues of the area were swabbed with a dry cotton swab. The subcutaneous tissue swab was positive for brown snake venom.