Regional Coordinator Center for Rare Diseases, Academic hospital of Udine, p.zzale SM della Misericordia 15, 33100, Udine, Italy. annalisa.sechi@asufc.sanita.fvg.it. Department of Medicine, University of Udine, Udine, Italy. Neuroimmunology and Muscle Pathology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy. International Center for the Assessment of Nutritional Status (ICANS), Department of Food Environmental and Nutritional Sciences (DeFENS), University of Milan, Milan, Italy. Institute of Biomedical Technologies, National Research Council, Segrate, Italy. Institute of Hygiene and Clinical Epidemiology, Academic hospital of Udine, Udine, Italy. Division of Endocrinology, Metabolic Diseases and Nutrition, Academic Hospital of Udine, Udine, Italy. Regional Coordinator Center for Rare Diseases, Academic hospital of Udine, p.zzale SM della Misericordia 15, 33100, Udine, Italy. Neurological Unit 1, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy.