ACUTE INTERMITTENT PORPHYRIA WITH TRANSIE NT PARESIS AND CONTRACTURE - EVIDENCE OF INITIAL MYOPATHY DYSFUNCTION

A 70-year old man with acute intermittent porphyria had acute transien t bibrachial paresis with moderate contracture of the involved muscles , which showed electrical silence in a conventional electromyographic investigation with surface electrodes placed over the contracted muscl e belly (filter: 20Hz-2 Hz, amplifier 50 mu V) Slow finger movements w ere still possible and showed typical muscle-action potentials. This e lectroclinical correlation points to myopathic localized dysfunction,p erhaps similar to rare case reports with patients haveing metabolic my opathy of McArdle's type.