Clinical Implication of Abnormal Spontaneous Activities in Polymyositis or Dermatomyositis

J Korean Assoc EMG Electrodiagn Med 2008;10(2):124-129.
Published online December 1, 2008.

Abstract

Objective: To analyse the relationship between severity of abnormal spontaneous activities and musclepower and serum muscle enzyme level in patients with polymyositis or dermatomyositis.Methods: We studied 15 patients who were diagnosed with polymyositis or dermatomyositis. They wereassessed by clinical findings, electromyography and clinical laboratory test. Severity of electromyographicfindings was classified into mild and severe groups based on amount of abnormal spontaneous activities.Results: Degree of abnormal spontaneous activities was negatively correlated with muscle power, especiallyin proximal muscles of upper extremity. Patients with severe abnormal spontaneous activitiesshowed higher creatine kinase level than that of mild group.Conclusion: Severity of abnormal spontaneous activities could provide supportive information to assessthe disease activity in patients with polymyositis or dermatomyositis.

Key Words: Polymyositis, Dermatomyositis, Abnormal spontaneous activity