Clinical electrophysiological and pathological study on hereditary sensory and autonomic neuropathy type I in a Chinese family

Objective: To report clinical, electrophysiological and pathological changes in type I of hereditary sensory and autonomic neuropathy (HSAN) in a Chinese family. Methods: The proband was a 28-year old man with pain loss in both legs as well as painless ulcer over 1 year. His mother also suffered from numbness and multiple ulcer of feet in her thirties. Sympathetic skin response (SSR), motor and sensory nerve conduction velocity as well as sural nerve biopsy were performed in the proband. Results: The amplitude of SSR was delayed in the hands and disappeared in the feet. Sensory nerve conduction velocity (SCV) was slow in the upper limbs (the SCV of right ulnar nerve was 33 m/s and of left median nerve was 45 m/s) and vacant in the low limbs. Motor nerve conduction velocity was mildly decreased in the upper limbs and markedly slowed down or did not react in the low limbs. Sural nerve biopsy showed total loss of myelinated fibers and marked loss of unmyelinated fibers. Conclusions: Our study confirmed the existence of type I HSAN in China. Both myelinated and unmyelinated fibers were involved. SSR, evaluating the function of sympathetic nerve, is useful for the diagnosis of HSAN.