[Demyelinating nervous lesions in myalgia-eosinophilia syndrome induced by L Tryptophan].

A case of severe peripheral nerve lesions in a patient with eosinophilia-myalgia syndrome induced by L-Tryptophan is reported. Both superficial radial nerves were very tender on palpation. Biopsy of the radial nerve showed myelin abnormalities of the type observed in experimental chronic nerve entrapment. Nerve lesions included asymmetrical distortion of the myelin sheath, segmental demyelination, axonal degeneration and regeneration. Such abnormalities suggest that mechanical factors, presumably due to proliferation of connective tissue, play a role in the nerve lesions observed in this patient.