Pufferfish exposure and presumed tetrodotoxicosis in Australian dogs: 372 cases (2007-2018)

Tetrodotoxin (TTX) is a neurotoxin found in pufferfish that results in the blockade of excitatory conduction and clinical signs including gastrointestinal upset and paralysis. The objectives of this study were to describe the epidemiology of pufferfish exposure and presumed tetrodotoxicosis in dogs, and to determine associations with the development of tetrodotoxicosis.

This was a multicentre historical cohort study with cases enrolled from veterinary hospitals in Perth Western Australia, and southeast Queensland. A medical record search identified cases between January 1^st 2007 and 5^th October 2018. Dog signalment, details of pufferfish exposure and veterinary presentation, clinical signs, treatment and outcome were recorded. Chi square tests were used to investigate the association between pufferfish exposure features and development of presumed tetrodotoxicosis.

Three hundred and seventy-two dogs were included. Two hundred and seventeen had pufferfish exposure only, while 155 dogs developed presumed tetrodotoxicosis. Gastrointestinal signs were the most common clinical signs prior to presentation (149/372, 40.1%), followed by neuromuscular signs (40, 10.8%). Dogs were significantly more likely to show clinical signs of tetrodotoxicosis if they ingested more than one pufferfish and had a delay to presentation of more than 2 h. Most dogs had gastrointestinal decontamination and were treated as outpatients (292, 78.8%). Eight received mechanical ventilation. All but 4 dogs survived (369/372); two dogs died naturally and two were euthanised.

Clinical signs are generally mild when presumed tetrodotoxicosis occurs after pufferfish ingestion in dogs. The prognosis for complete recovery is good with timely initiation of decontamination and supportive care.