Acquired myasthenia gravis in a Jack Russell terrier

Myasthenia gravis is an uncommon but important condition of dogs. The clinical signs usually include episodic weakness and regurgitation. The diagnosis is made by a combination of appropriate clinical signs having ruled out conditions with similar presentations, and supportive results of repetitive nerve stimulation testing, the edrophonium challenge test and/or positive serum acetylcholine receptor antibody titres. The dog in this case report is of interest due to the diagnosis being made on the basis of oesophageal response to the edrophonium challenge test, as measured by fluoroscopy. Treatment involves changes to feeding practices, as well as the addition of anti-cholinesterase compounds and corticosteroids. The long term prognosis is fair.