title: [Neurophysiological study in slow-channel congenital myasthenic syndrome: case report].
abstract: The slow-channel syndrome is one of the congenital myasthenic syndromes attributed to inherited kinetic disorders of the ion channel of the acetylcholine receptor of the neuromuscular junction. This is a case report of 25-years-old man with progressive ptosis and limitation of ocular movements since infancy, presented a 6-years history of worse of the external ophthalmoparesis and muscular weakness in the shoulders and hands. The motor nerve conduction studies after a supramaximal single stimulus disclosed a double compound muscle action potential (CMAP) that disappeared after a voluntary contraction of 30 seconds. Repetitive stimulation of facial and spinal accessory nerves showed a CMAP decrement greater than 10% with disappeared of the second potential. The patient received fluoxetine with mild improvement of muscular weakness, but persisted with: ptosis, limitation of ocular movements and repetitive CMAP in the motor nerve conduction study. The characteristic of disease are discussed.
authors.affiliation: Serviço de Doenças Neuromusculares, Hospital de Clínicas, Universidade Federal do Paraná, Curitiba, PR, Brazil.
authors.forename: Paulo José
authors.initials: PJ
authors.lastname: Lorenzoni
authors.forename: Cláudia Suely Kamoi
authors.initials: CS
authors.lastname: Kay
authors.forename: Walter Oleschko
authors.initials: WO
authors.lastname: Arruda
authors.forename: Rosana Herminia
authors.initials: RH
authors.lastname: Scola
authors.forename: Lineu César
authors.initials: LC
authors.lastname: Werneck
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D000328:Adult; D004558:Electric Stimulation; D004576:Electromyography; D004594:Electrophysiology; D005473:Fluoxetine / Q000627:therapeutic use; D006801:Humans; D008297:Male; D020294:Myasthenic Syndromes, Congenital / Q000175:diagnosis / Q000188:drug therapy / Q000503:physiopathology*; D009431:Neural Conduction / Q000502:physiology*; D009469:Neuromuscular Junction / Q000503:physiopathology; D017367:Selective Serotonin Reuptake Inhibitors / Q000627:therapeutic use
chemical_list: D005473:Fluoxetine; D017367:Selective Serotonin Reuptake Inhibitors