To investigate the weight of visual and proprioceptive inputs, measured indirectly in standing position control, in patients with chronic acquired demyelinating polyneuropathy (CADP). Prospective case study. Twenty-five patients with CADP and 25 healthy controls. Posture was recorded on a double force platform. Stimulations were optokinetic (60°/s) for visual input and vibration (50 Hz) for proprioceptive input. Visual stimulation involved 4 tests (upward, downward, rightward and leftward) and proprioceptive stimulation 2 tests (triceps surae and tibialis anterior). A composite score, previously published and slightly modified, was used for the recorded postural signals from the different stimulations. Despite their sensitivity deficits, patients with CADP were more sensitive to proprioceptive stimuli than were healthy controls (mean composite score 13.9 ((standard deviation; SD) 4.8) vs 18.4 (SD 4.8), p = 0.002). As expected, they were also more sensitive to visual stimuli (mean composite score 10.5 (SD 8.7) vs 22.9 (SD 7.5), p <0.0001). These results encourage balance rehabilitation of patients with CADP, aimed at promoting the use of proprioceptive information, thereby reducing too-early development of visual compensation while proprioception is still available.

Erythromelalgia may be primary or secondary to an underlying medical condition. Association with small fiber neuropathy and axonal large fiber peripheral neuropathy has been described. Erythromelalgia in the setting of acquired demyelinating neuropathy has not been reported. We report a 52-year-old woman with severe erythromelalgia, pain and burning, progressive weakness, hyporeflexia and distal pan-sensory deficits. Cerebrospinal fluid protein was 219 mg/dL. Nerve conduction study revealed extreme (ten-fold) prolongation of distal motor latencies, markedly slow motor nerve conduction, reduced terminal latency index, reduced distal compound muscle action potential (CMAP) amplitude, possible conduction blocks, and distal denervation. Treatment with intravenous immunoglobulin, prednisone and azathioprine resulted in marked clinical and electrophysiological improvement. Our patient fulfills the diagnostic criteria for chronic inflammatory demyelinating polyneuropathy (CIDP); however, the unique electrodiagnostic features and presentation with erythromelalgia may represent a CIDP variant or a novel dysimmune neuropathy, or may partly be related to neurotoxic effects of prior alcohol abuse.