Coexistence of hereditary motor and sensory neuropathy type Ia and IgM paraproteinemic neuropathy.

A patient with minimal motor dysfunction dating from early childhood developed more rapidly progressive distal weakness and positive sensory symptoms due to peripheral neuropathy in the fourth decade of life. DNA analysis showed the partial duplication of chromosome 17p associated with hereditary motor and sensory neuropathy type Ia. In addition, the patient had an IgM paraproteinemia and the typical morphological features of IgM paraproteinemic neuropathy on nerve biopsy.