Paroxysmal Exercixe-Induced Dyskinesia (PED)

Paroxysmal movement disorders are a group of diverse neurological diseases which could be characterized by episodes of involuntary movements. The Paroxysmal Exercise-Induced Dyskinesia (PED) is one form of these paroxysmal movement disorders and is usually induced by stress situations or excitement.

In the breed Shetland Sheepdog, a variant in the PCK2 (phosphoenolpyruvate caboxykinase 2) gene has been found to cause PED. Affected dogs show episodes of generalized ataxia with an unusual gait pattern (hypermetria) and muscular tension (hypertonia) of all limbs, reduced mentation and mild tremor. The episodes could vary from minutes to hours and are triggered by inner tension, like playing, after being startled by noise or hot weather. Laboratory tests indicate a mild lactic acidosis and lactaturia, mildly increased serum creatine kinase (CK) levels and hypoglycemia.

Stress management, a specific diet (gluten- and grain-free, seafood-bases with a high tryptophan content) as well as a pharmacological therapy with antiepileptic drugs (carbonic anhydrase inhibitors like acetazolamide or zonisamide) can have an impact on episode frequency or even result in partial or complete suppression of the episodes. Therefore, the symptoms of the disease can be reduced significantly to enable a good quality of life with a normal life expectancy.