Phenotypic characteristics of paroxysmal dyskinesia in 25 cats.

OBJECTIVES

Paroxysmal dyskinesia has, to date, been reported only systematically in Sphynx cats. This study aims to describe paroxysmal dyskinesia in additional breeds.

MATERIALS AND

METHODS

The medical records of cats from multiple hospitals presenting with episodes consistent with paroxysmal dyskinesia between 2020 and 2025 were retrospectively reviewed, and those with available video footage at presentation were included.

RESULTS

Twenty-five cats were included. Domestic shorthair cats (11/25; 44%) were overrepresented. Median age at presentation was 3.5 years (range: 1 to 14 years). During an episode, cats were upright standing (14/25; 56%) or crawling (11/25; 44%). Most common signs were shifting limb dystonia (25/25; 100%), bradykinesia (slow-motion movement) (11/25; 44%), abnormal gait (11/25; 44%), kyphosis (10/25; 40%), tail dystonia (10/25; 40%), cervical dystonia (9/25; 36%) with dystonic head tremor (3/25; 12%), falling (7/25; 28%) or 'kneading' digits (5/25; 20%). Neurological examination was normal in all cats. Treatment was attempted in 11/25 (44%) cats with a gluten-free diet trial (6/11; 55%). Gluten-free diet trial (4/6) and levetiracetam (2/2) decreased episodes of paroxysmal dyskinesia. Most cats (21/25; 84%) were presumptively diagnosed with idiopathic paroxysmal non-kinesigenic dyskinesia, whereas 4/25 (16%) were diagnosed with presumptive paroxysmal gluten-sensitive dyskinesia.

CLINICAL SIGNIFICANCE: Idiopathic paroxysmal dyskinesia occurs in multiple cat breeds and has some distinct clinical features compared to dogs such as crawling, crossing of the thoracic limbs resembling proprioceptive ataxia, bradykinesia (slow-motion movements), 'kneading' of the digits or tail dystonia.