[Seizure disorders in the dog. 1. Clinical features and differential diagnosis]

For differential diagnosis, therapy, and prognosis of seizures in dogs it is recommended to distinguish between two groups of diseases: 1. Epilepsy is diagnosed if seizures occur repeatedly without an active, underlying disorder. Idiopathic epilepsy occurs most commonly. A hereditary component has been demonstrated in several breeds. Symptomatic epilepsy results from previous resolved forebrain disorders, which cause epileptic seizures through scar formation. 2. Seizures are caused by active structural forebrain disease or metabolic-toxic imbalances. Upon initial presentation of the dog, a preliminary classification may be achieved with the seizure history, clinical and neurological examination, and routine laboratory evaluation. The diagnosis of idiopathic epilepsy is based on typical seizure history and exclusion of structural forebrain disease and metabolic-toxic imbalances with special laboratory testing, CSF examination, and brain scanning procedures.