Mateja Baruca1, Lea Leonardis2, Simon Podnar2, Tanja Hojs-Fabjan3, Anton Grad4, Aleš Jerin5, Rok Blagus6, Saša Šega-Jazbec1. 1. University Medical Centre Ljubljana, Department of Neurology, Zaloška cesta 2,1000, Ljubljana, Slovenia. 2. University Medical Centre Ljubljana, Institute of Clinical Neurophysiology, Ljubljana, Slovenia. 3. University Medical Centre Maribor, Department of Neurology, Maribor. 4. General Hospital of Isola, Isola, Slovenia. 5. University Medical Centre Ljubljana, Clinical institute of Clinical Chemistry and biochemistry, Ljubljana, Slovenia. 6. Institute for Biostatistics and Medical Informatics, University of Ljubljana, Faculty of Medicine, Ljubljana, Slovenia.
Abstract
INTRODUCTION: Single fiber electromyography (SFEMG) is the most sensitive diagnostic tool for diagnosis of myasthenia gravis (MG). Its prognostic value is not known. METHODS: We retrospectively analyzed the clinical course of 232 MG patients who presented with only mild symptoms and had SFEMG of the orbicularis oculi muscle. We correlated their SFEMG results with the severity of their later clinical course. RESULTS: During the observation period 39 patients (17%) developed severe disease exacerbations, and 193 (83%) remained stable. Patients with severe disease exacerbation had a significantly higher mean jitter value (P < 0.0001), a greater percentage of fibers with increased jitter (P < 0.0001), and/or impulse blocking (P < 0.0001) on SFEMG. CONCLUSIONS: The extent of the SFEMG abnormalities in this study correlated with the later clinical course of MG. Muscle Nerve 54: 1034-1040, 2016.
INTRODUCTION: Single fiber electromyography (SFEMG) is the most sensitive diagnostic tool for diagnosis of myasthenia gravis (MG). Its prognostic value is not known. METHODS: We retrospectively analyzed the clinical course of 232 MGpatients who presented with only mild symptoms and had SFEMG of the orbicularis oculi muscle. We correlated their SFEMG results with the severity of their later clinical course. RESULTS: During the observation period 39 patients (17%) developed severe disease exacerbations, and 193 (83%) remained stable. Patients with severe disease exacerbation had a significantly higher mean jitter value (P < 0.0001), a greater percentage of fibers with increased jitter (P < 0.0001), and/or impulse blocking (P < 0.0001) on SFEMG. CONCLUSIONS: The extent of the SFEMG abnormalities in this study correlated with the later clinical course of MG. Muscle Nerve 54: 1034-1040, 2016.