[High frequency discharges as a non-specific EMG activity in adult acid maltase deficiency (author's transl)].
The clinical diagnosis of a 34-year-old man was muscular dystrophy of the ascending limb-girdle type. There were no detectable signs of myotonia. Histological and biochemical investigations confirmed an acid maltase deficiency (AMD). Electromyography demonstrated a myopathic pattern, fibrillation potentials, normal nerve conduction velocity, and so-called pseudomyotonic or bizarre high frequency discharges. In the literature this EMG activity has been described as characteristic for AMD. But it seems to be a nonspecific EMG sign, which occurs in myogenic and neurogenic lesions such as myositis, metabolic and dystrophic myopathy, nuclear damage, radiculopathy, and neuropathy. It is therefore of little diagnostic value.
D000328:Adult; D003937:Diagnosis, Differential; D004576:Electromyography; D005071:Evoked Potentials; D006008:Glycogen Storage Disease / Q000175:diagnosis*; D006009:Glycogen Storage Disease Type II / Q000175:diagnosis*; D006801:Humans; D008297:Male; D009123:Muscle Hypotonia / Q000175:diagnosis; D009133:Muscular Atrophy / Q000175:diagnosis
Pseudomyotone EMG-Entladungen als unspezifischer Befund bei Muskelglykogenose Typ II (Morbus Pompe).