how to cite this article: mohammadi m. electrodiagnostic studies, “role in the diagnosis and follow-up in children with pompe disease”. iran j child neurol autumn 2012; 6:4 (suppl. 1):23. pls see pdf.

The presence of myotonia and paramyotonia on clinical examination and of myotonic discharges during electrodiagnostic (EDX) studies are important for the diagnosis of certain neuromuscular conditions. The increased muscle activity of myotonia produces muscle stiffness that improves with repeated activity. Paramyotonia produces a similar symptom, but the stiffness paradoxically increases with ac...

INTRODUCTION Two previously reported Norwegian patients with painful muscle cramps and giant myotonic discharges were genotyped and compared with those of members of 21 families harboring the same mutation. METHODS Using primers specific for SCN4A and CLCN1, the DNA of the Norwegian family members was amplified and bidirectionally sequenced. Clinical and neurophysiological features of other f...

BACKGROUND Myotonic dystrophy type 2 (DM2) is an autosomal dominant, multisystem disorder caused by a CCTG tetranucleotide repeat expansion located in intron 1 of the zinc finger protein 9 gene (ZNF9 gene) on chromosome 3q 21.3. OBJECTIVES To describe the clinical, electrophysiologic and pathologic findings in patients with myotonic dystrophy 2. METHODS We evaluated 10 patients genetically,...

We describe a 38-yr-old polio survivor with newly developed weakness from myotonic dystrophy. He suffered muscle atrophy and weakness in his legs as a result of poliomyelitis at the age of 3 yrs. After a stable interval of about 30 yrs, he felt new weakness and fatigue in his legs. Electromyography revealed generalized myotonic discharges, early recruitment, and findings of chronic denervation ...

Centronuclear myopathy (CNM) is a rare hereditary myopathy characterized by centrally located muscle fiber nuclei. Mutations in the dynamin 2 (DNM2) gene are estimated to account for about 50 % of CNM cases. Electromyographic recordings in CNM may show myopathic motor unit potentials without spontaneous activity at rest. Myotonic discharges, a distinctive electrical activity caused by membrane ...

A case of myotubular myopathy is described which is unusual because of bilateral cataracts and prominent myotonic-like discharges on the EMG. The significance of these findings is discussed in relation to dystrophia myotonica.

In myotonic muscular dystrophy, abnormal muscle Na currents underlie myotonic discharges. Since the myotonic muscular dystrophy gene encodes a product, human myotonin protein kinase, with structural similarity to protein kinases, we tested the idea that human myotonin protein kinase modulates skeletal muscle Na channels. Coexpression of human myotonin protein kinase with rat skeletal muscle Na ...

schwartz-jampel syndrome, (sjs) is a rare disorder characterized by myotonia, joint contracture, facial dysmorphism and growth retardation, we present three siblings (two sisters and one brother) 19,24 and 27 years old from consanguineous healthy parents with sjs. their clinical features were similar to those previously described. motor and sensory nerve conduction study (ncs) were compatible w...

We investigated electrophysiologically the unaffected parents of patients with recessive myotonia congenita. We studied 18 families, in nine of which the diagnosis was confirmed by molecular genetics. Brief myotonic discharges were present in at least one parent in 67% of the families. Fathers were more likely than mothers to show these discharges. The difficulty in distinguishing very mildly a...