[Neurophysiological study in slow-channel congenital myasthenic syndrome: case report].
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.
Lorenzoni
Paulo José
PJ
Serviço de Doenças Neuromusculares, Hospital de Clínicas, Universidade Federal do Paraná, Curitiba, PR, Brazil.
Kay
Cláudia Suely Kamoi
CS
Arruda
Walter Oleschko
WO
Scola
Rosana Herminia
RH
Werneck
Lineu César
LC
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
D005473:Fluoxetine; D017367:Selective Serotonin Reuptake Inhibitors