[Multifocal demyelinating neuropathy with persistent conduction blocks and continuous muscular activity]

A patient developed an initially asymmetric sensory-motor neuropathy, with definite predominance in upper limbs. The examination also disclosed a markedly impaired muscle relaxation. The neurophysiological study showed conduction blocks with continuous muscle activity consisting of myokymias fasciculations and muscle cramps which disappeared after the anesthetic block of the distal nerve segments. In the sural nerve biopsy significant abnormalities were not found. After prednisone and carbamazepine therapy in usual doses the symptoms reverted and the conduction blocks persisted. Neuropathy with persistent conduction blocks is an uncommon disease which exceptionally results in a clinically apparent syndrome of continuous muscle activity. Its recognition is important, as symptoms can disappear after correct therapy.