LA MALADIE DE CHARCOT MARIE TOOTH

Abstract

The authors present a case of Charcot Marie Tooth disease, with dominant inherited pattern. Microscopic and ultrastructural studies of a nerve specimen showed the typical changes already known in this entity. Paraffin and epon embedded material revealed under light microscopy a diminution in the number of myelinated fibers with a marked increase of the connective tissue, and characteristic onion bulb formations. Ultrastructural studies have confirmed that these structures are made of elongated and flattened Schwann cells, concentrically arranged around an axon of fair diameter and generally covered with myelin. Between the layers of Schwann cells which included many small unmyelinated fibers were seen many bundles of collagen parallel with the axon. Teasing of the fibers has shown segmental demyelination. In conclusion, the authors discuss the place of this entity in the large group of the familial degenerative diseases of the nervous system. The metabolic abnormalities already found in Refsum and Dejerine Sottas diseases indicate the line to follow for the explanation of the pathogenesis of Charcot Marie Tooth disease.