Recommendations for the diagnosis and treatment of paroxysmal kinesigenic dyskinesia: an expert consensus in China

Abstract

Paroxysmal dyskinesias are a group of neurological diseases characterized by intermittent episodes of involuntary movements with different causes. Paroxysmal kinesigenic dyskinesia (PKD) is the most common type of paroxysmal dyskinesia and can be divided into primary and secondary types based on the etiology. Clinically, PKD is characterized by recurrent and transient attacks of involuntary movements precipitated by a sudden voluntary action. The major cause of primary PKD is genetic abnormalities, and the inheritance pattern of PKD is mainly autosomal-dominant with incomplete penetrance. The proline-rich transmembrane protein 2 (PRRT2) was the first identified causative gene of PKD, accounting for the majority of PKD cases worldwide. An increasing number of studies has revealed the clinical and genetic characteristics, as well as the underlying mechanisms of PKD. By seeking the views of domestic experts, we propose an expert consensus regarding the diagnosis and treatment of PKD to help establish standardized clinical evaluation and therapies for PKD. In this consensus, we review the clinical manifestations, etiology, clinical diagnostic criteria and therapeutic recommendations for PKD, and results of genetic analyses in PKD patients performed in domestic hospitals.

PRRT2 Gene Analysis of Paroxysmal Kinesigenic Dyskinesia (PKD) in Thai Children

“…These findings correspond well with three Korean and one Chinese studies. 7,14 More than 80 different PRRT2 mutations have been identified 10 , including truncating, missense, and splice-site mutations and a complete PRRT2 deletion. Of these, the c.649dupC frameshift mutation has been most commonly found (80.5%) in PKD patients.…”

“…7,8 Although the PRRT2 gene is the most common gene identified in patients diagnosed PKD, PRRT2 mutations have not been detected in up to 40.0% of the familial and most of the sporadic PKD cases. Therefore, other causative PKD genes could be found in patients with negative PRRT2 mutations including SLC2A1 1 , SCN8A 9 , KCNMA1, KCNA1, DEPDC5 10 and a deletion of chromosome 16p11.2. 11 As PKD is a paroxysmal disorder, it can be misdiagnosed as a seizure disorder, especially when the EEG reveals abnormalities.…”

“…8 The clinical spectrum of PRRT2-related diseases involves benign familial infantile convulsions (BFIC), infantile convulsions with choreoathetosis (ICCA), hemiplegic migraine, and episodic ataxia. 8 Apart from the PRRT2 mutations, other causative genes of PKD have been reported, such as SLC2A1 1 , SCN8A 9 , KCNMA1, KCNA1, DEPDC5 10 and a deletion of chromosome 16p11.2. 11 A study of clinical phenotypes and genetic testing in Thai PKD patients has never been done.…”

Paroxysmal Kinesigenic Dyskinesia Secondary to Pseudohypoparathyroidism Responding to Correction of Calcium

“…Paroxysmal kinesigenic dyskinesia (PKD) is the most common type of paroxysmal dyskinesia that can be inherited or secondary. 1 The secondary causes of PKD include head trauma, multiple sclerosis, perinatal hypoxic encephalopathy, basal ganglia calcifications, idiopathic hypoparathyroidism, pseudohypoparathyroidism (PHP), moyamoya disease, and HIV infection. Secondary PKD is thought to be common but less reported in the literature.…”

“…The abnormal involuntary movements include dystonia, chorea, athetosis, or ballism in isolation or combination. Paroxysmal kinesigenic dyskinesia (PKD) is the most common type of paroxysmal dyskinesia that can be inherited or secondary 1 . The secondary causes of PKD include head trauma, multiple sclerosis, perinatal hypoxic encephalopathy, basal ganglia calcifications, idiopathic hypoparathyroidism, pseudohypoparathyroidism (PHP), moyamoya disease, and HIV infection.…”