Chronic immune polyradiculopathies: Three clinical variants of one disease?

Abstract

Introduction: Chronic immune polyradiculopathies (sensory, motor, and mixed) are uncommon.

Methods: In this single-center, retrospective study, the inclusion criteria for participants were progressive sensory ataxia and/or areflexic limb weakness; tibial somatosensory evoked potential (SSEP) abnormalities of the N22 and P40 potentials with normal sensory and motor nerve conduction studies or root involvement, according to magnetic resonance imaging (MRI); and albuminocytological dissociation.

Results: Eight patients were included in our study. Two had weakness, two had sensory ataxia, and four had both weakness and ataxia. Patients with weakness had abnormal SSEPs and patients with sensory ataxia also had absent F waves. Electromyography showed chronic denervation. MRI scans confirmed thickening and enhancement of roots. The patients responded to corticosteroid treatment.

Discussion: The overlapping clinicoelectrophysiological findings and similarities in radiological and therapeutic responses suggest that these entities are clinical variants of the same disease. The terms CIS(m)P, CI(s)MP, and CISMP (for chronic immune sensory motor polyradiculopathy) could be used to denote the predominant clinical involvement.

Keywords: Chronic Immune Demyelinating Polyneuropathy, Chronic Immune Motor Polyradiculopathy, Chronic Immune Sensori Motor Polyradiculopathy, Chronic Immune Sensory Polyradiculopathy, Magnetic Resonance Neurography, Somatosensory Evoked Potentials.