DEMYELINATING HEREDITARY NEUROPATHIES IN CHILDREN - A MORPHOMETRIC AND ULTRASTRUCTURAL-STUDY

Twenty-three cases of hereditary demyelinating neuropathies are report ed, 13 with different types of hereditary motor and sensory neuropathy (HMSN) and 9 with globoid cell or meta-chromatic leucodystrophies. Ul trastructural and morpho-metric studies showed some critical pathologi cal features emphasizing: 1) the variability of the recessive forms of HMSN; 2) the morphological distinction between HMSN type I and type I II; and 3) differences between these types of HMSN and other ''onion b ulb'' neuropathies such as those found in leucodystrophies, which acco unt for distinct underlying mechanisms.