[Polymorphism of the continuous muscle fibers activity syndrome. Possible relationship with Morvan's fibrillary chorea (author's transl)].

Two cases presenting the main features of the continuous muscle activity syndrome (neuromyotonia) are reported. The clinical particularities between the two patients are under lined. The second case is special because of its acute and reversible evolution and the possible role of gold salts in its etiology. This latter point suggests Morvan's fibrillary chorea. The possible relationships between the two syndrome are discussed.