P.418 - GFPT1-related limb-girdle myasthenia: First case reported in Argentina

Most congenital myashtenic syndrome (CMS) are caused by defects in endplate (EP)-specific proteins. Recently proteins distributed in many tissues, namely plectin, GFPT1, and DPAGT1, are also CMS targets. Both GFPT1 and DPAGT1 are involved in glycosylation and mutations in either protein result in limb-girdle myasthenia with tubular aggregates(TA) in type 2 muscle fibres. We present a male patient with GFPT1 limb-girdle CMS. A 48-year-old Argentinian male patient who had a longstanding proximal limb muscle weakness was considered during this a time a muscular dystrophy or a congenital myopathy. We performed whole exome sequencing and DNA disclosed two mutations (c.1309T>C (p.Phe437Leu) and c.686-2A>G) in GFPT1. We reviewed previous muscle biopsies, that showed infrequent TAs and severe autophagia,and also performed RNS and SFEMG that showed impairment of the neuromuscular transmission. We present a patient with a GFPT1 limb-girdle CMS, the first one in our country. Identification of Limb-girdle CMS among patients with muscle disorders is important because are potentially treatable