Pure autonomic failure with cold induced sweating.

Pure autonomic failure (PAF) is a progressive autonomic neurodegenerative disorder. Cold induced sweating occurred in syndromes with mutations in CRLF1 and CLCF1 genes and in a case of cervical dissection. A patient with PAF developed sweating induced by cool ambient temperatures. He had severe orthostatic hypotension, abnormal cardiovagal reflexes, and paradoxical sweating in the upper trunk at a room temperature of 18°C. Skin biopsy showed involvement of somatic epidermal unmyelinated nerve fibers. Quantitative sensory testing showed abnormal thresholds to all thermal modalities. Possible mechanisms include cold induced noradrenaline release in remaining autonomic innervation and a supersensitive sudomotor response.