Abnormal responses to cold stress in Charcot-Marie-Tooth I syndrome.

In Charcot-Marie-Tooth syndrome (CMT, Hereditary Motor Sensory Neuropathy), patient complaints of cold intolerance are common but their peripheral responses to cold have not been documented. Using digital plethysmography, a simple test of vascular reactivity with 1 minute cold stress, 20 unrelated adult CMT patients showed a significantly increased average heart rate and decreased average arterial oxygen saturation following cold when compared to 50 age-matched normal controls. There did not appear to be a unique or characteristic CMT vascular reaction to cold stress in CMT patients because their abnormal peripheral vascular responses were variable. Variability in CMT neuropathic responses to cold is consistent with the known irregular segmental demyelination of CMT peripheral nerves as well as abnormal CMT sweating patterns. Though understanding the precise patterns of CMT patient peripheral nerve disturbances remains difficult, awareness of CMT patient's abnormal responses to cold may facilitate CMT patient care and rehabilitation.