[A case of HNPP presenting with late onset of symptoms, chronic progressive course and sensory impairment in face and trunk].

A 69-year-old man was admitted with a chief complaint of progressive muscle weakness and tingling sensation in the distal portion of all extremities since the age of 55. On neurological examination, sensory impairment of all modalities was noted in the right side of face, segmental areas of the right Th4-10 and the distal portion of four extremities. Symmetrical muscle weakness and atrophy was also found over the distal portion of all extremities. All deep tendon reflexes except biceps brachii reflexes were absent. Neurophysiological studies, however, rather indicated mononeuritis multiplex in this case. The biopsied specimen of the sural nerve showed a significant decrease in large myelinated fibers and many tomaculous changes. The gene analysis revealed deletion in the CMT 1A locus on chromosome 17p11.2, providing evidence for the diagnosis of hereditary neuropathy with liability to pressure palsies (HNPP). The development of sensory impairment in face or thoracic nerves is quite rare in HNPP, indicating that there exists considerable phenotypic heterogeneity in the disease.