Clinical characterization of epilepsy of unknown cause in cats.
BACKGROUND
The diagnosis of feline epilepsy of unknown cause (EUC) requires a thorough diagnostic evaluation, otherwise the prevalence of EUC could be overestimated.


OBJECTIVE
Feline EUC is a clinically defined disease entity, which differs from feline hippocampal necrosis by the absence of magnetic resonance imaging (MRI) signal alteration of the hippocampus. The objectives of this study were (1) to evaluate the prevalence of EUC in a hospital population of cats by applying well-defined inclusion criteria, and (2) to describe the clinical course of EUC.


METHODS
Eighty-one cats with recurrent seizures.


METHODS
Retrospective study--medical records were reviewed for cats presented for evaluation of recurrent seizures (2005-2010). Inclusion criteria were a defined diagnosis based on laboratory data, and either MRI or histopathology. Final outcome was confirmed by telephone interview with the owner. Magnetic resonance images were reviewed to evaluate hippocampal morphology and signal alterations.


RESULTS
Epilepsy of unknown cause was diagnosed in 22% of cats with epilepsy. Physical, neurologic, and laboratory examinations, and either 1.5 T MRI and cerebrospinal fluid analysis or postmortem examination failed to identify an underlying cause. Cats with EUC had a higher survival rate (P < .05) and seizure remission occurred frequently (44.4%).


CONCLUSIONS
A detailed clinical evaluation and diagnostic imaging with MRI is recommended in any cat with recurrent seizures. The prognosis of cats with normal MRI findings and a clinical diagnosis of EUC are good. Standardized imaging guidelines should be established to assess the hippocampus in cats.
Clinic of Small Animal Medicine, Ludwig-Maximilians University, Munich, Germany.
A M
AM
Wahle
A
A
Brühschwein
K
K
Matiasek
K
K
Putschbach
E
E
Wagner
R S
RS
Mueller
A
A
Fischer
D000818:Animals; D002371:Cat Diseases / Q000453:epidemiology / Q000503:physiopathology*; D002415:Cats; D004827:Epilepsy / Q000453:epidemiology / Q000503:physiopathology / Q000662:veterinary*; D053208:Kaplan-Meier Estimate; D008279:Magnetic Resonance Imaging / Q000662:veterinary; D015995:Prevalence; D012189:Retrospective Studies
Feline; Hippocampus; Outcome; Seizure