Unravelling of the paroxysmal dyskinesias

Abstract

Paroxysmal dyskinesias (PxD) refer to a rare group of clinically and genetically heterogeneous disorders presenting with recurrent attacks of abnormal movements, typically dystonia, chorea or a combination thereof, without loss of consciousness. Classically, PxD have been categorised according to their triggers and duration of the attacks, but increasing evidence suggests that there is a certain degree of clinical and genetic overlap and challenges the concept that one phenotype is attributable to one single aetiology. Here we review the increasing spectrum of genetic conditions, as well as of other non-genetic disorders, that might present with PxD, provide criteria for case definition and propose a diagnostic workup to reach a definitive diagnosis, on which treatment is heavily dependent.

Generalized Dystonia and Paroxysmal Dystonic Attacks due to a Novel ATP1A3 Variant

“…1,2,3 In our cases, the ATP1A3 variant produces a phenotype similar to PNKD, particularly the wide range of duration and frequency, the lack of sudden movement or exercise as precipitant, and the presence of aggravating factors such as stress and fatigue. 1,2 However, in contrast to PNKD, our patients also presented with interictal mild dystonia, speech arrest, and intellectual disability.…”

Paroxysmal Asymmetric Dystonic Arm Posturing—A Less Recognized but Characteristic Manifestation of ATP1A3‐related disease

“…While paroxysmal dystonic posturing, or episodic worsening of a movement disorder is seen with various aetiologies—for example in PRRT2, GCH1, GLUT1, or ADCY5 ‐related disease, and various mitochondrial and metabolic diseases including glutaric aciduria—the episodic dystonic posturing in ATP1A3 ‐related disease highlighted here seems to be a distinct sign.…”

“…This is typically not seen in the majority of the above disorders, where dystonia is typically more generalized. Exercise‐induced dystonia, as seen with GCH1 or GLUT1 mutations, manifests most typically in the legs after prolonged exercise . Rarely, it can involve the hands after their prolonged use, but dystonic posturing of one arm would be very unusual.…”

“…Exercise-induced dystonia, as seen with GCH1 or GLUT1 mutations, manifests most typically in the legs after prolonged exercise. 8,9 Rarely, it can involve the hands after their prolonged use, but dystonic posturing of one arm would be very unusual. Lastly, of course, the trigger (exercise) would be readily identifiable.…”

Novel mutation of the PRRT2 gene in two cases of paroxysmal kinesigenic dyskinesia: Two case reports

“…Paroxysmal kinesigenic dyskinesia (PKD) is a rare condition characterized by recurrent brief episodes of dystonia, chorea, athetosis or a combination thereof, without alteration of consciousness. PKD may be considered as a pure form, where patients only present with dystonia, chorea and athetosis, or as a complicated form, were patients present with PKD combined with benign familial infantile convulsions or hemiplegic migraine (1). Episodes are usually triggered by sudden voluntary movements (1).…”