Effect of prolonged status epilepticus as a result of intoxication on epileptogenesis in a UK canine population

The aim of the present study was to investigate if prolonged status epilepticus (SE), secondary to a chemoconvulsant, can induce spontaneous recurrent seizures in dogs. Clinical records at two UK referral hospitals were searched for dogs that presented in SE secondary to intoxication. Dogs were only included in the study if there was clear historical evidence of intoxication and a prolonged SE. Clinical and follow-up information was retrieved and verified by using a combination of clinical records from the two hospitals and the referring veterinarian and by contacting the owners using a telephone questionnaire. Twenty dogs met the inclusion criteria: 17 presented for metaldehyde toxicity, one for moxidectin toxicity, one for theobromine toxicity and one for mycotoxin toxicity. Of these 20 dogs, three dogs had an SE duration between 0.5 and one hour, four dogs between one and 12 hours, 10 dogs between 12 and 24 hours and three dogs greater then 24 hours. Median follow-up time for the 20 dogs was 757 days (range 66 to 1663 days). No dog had any further seizures after its SE. The present study supports the view that dogs with a prolonged SE following intoxication with the aforementioned toxins might not need long-term treatment with antiepileptic drugs after the SE has been controlled.