Painless Fractures and Thermoregulation Disturbances in Sensory-Autonomic Neuropathy: Electrophysiological Abnormalities and Sural Nerve Biopsy

We describe the case of a young girl suffering from thermoregulation disturbances, painless fractures and arthropathy since early childhood. The patient was diagnosed as having a hereditary sensory autonomic neuropathy. Although needle EMG, conventional nerve conduction studies and somatosensory evoked potentials gave normal results, sympathetic skin responses (SSRs) were absent. Sural nerve biopsy showed a substantial reduction in the number of small myelinated and unmyelinated fibers.

We emphasize the importance of SSR testing in revealing a condition which is otherwise difficult to identify by electrophysiological techniques. The combined evidence of functional and morphological findings is strongly suggestive of selective peripheral nerve involvement.

Key words

Painless fractures - Autonomic neuropathy - Sympathetic skin response - Sural nerve biopsy

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