Toxin Induced Continuous Muscle Fiber Activity Syndrome

Abstract

Continuous Muscle Fiber Activity Syndrome describes rare heterogeneous group of conditions that exhibit sustained, diffuse motor unit activity due to hyperactivity of peripheral nerve motor axons. The disorder, which has both inherited and acquired forms, is characterized by muscular stiffness, cramps, fasciculation and weakness particularly in the limbs. We report a case 42 year old male who presented with easy fatigability and insidious onset gradually progressive difficulty in walking due to muscle stiffness in both lower limbs along with continuous twitching of muscles of all 4 limbs and chin. EMG study showed spontaneous, continuous, irregular rapid discharges of motor-unit potentials. doi: 10.5214/ans.0972.7531.2008.150405 Competing interests: None. Source of Funding: None Received Date: 25 Sept 2008 Revised Date: 15 Oct 2008 Accepted Date: 27 Oct 2008