Focal chronic inflammatory demyelinating polyradiculoneuropathy: Onset, course, and distinct features

• DOI: 10.1111/jns.12438
• Publication Date: 2021-03-04T11:59:40Z
• Authors: Charline Benoit; Juliette Svahn; Rabab Debs; Christophe Vanden...; Timothée Lenglet; Julie Zyss; Thierry Maisonobe; Karine Viala
• Keywords: Polyradiculoneuropathy; Multifocal motor neuropathy

Focal chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is defined as involving the brachial or lumbosacral plexus, one more peripheral nerves in upper lower limb (monomelic distribution). However, other auto-immune neuropathies such Lewis-Sumner syndrome (LSS) and multifocal motor neuropathy (MMN) can also have a focal onset. From retrospective cohort of 30 CIDP patients with monomelic onset dating back at least 2 years, we distinguished plexus involvement (focal [F-PN], n = 18) from those sensory sensorimotor (F-SMN, 7), purely (F-MN, 5) impairment located several nerves. Few (39%) F-PN had nerve conduction abnormalities, but majority showed proximal abnormalities somatosensory evoked potentials (80%), all hypertrophy and/or increased short tau inversion recovery image signal intensity on MRI. Impairment remained most (94%) patients, whereas developed limbs 57% F-SMN, 40% F-MN (P .015). The prognosis was significantly better: none an ONLS score > final follow-up visit, vs 43% F-SMN .026). Our findings large confirm existence different entities that are typically categorized under this term: hand, other, sensori-motor These two last subgroups appeared to be likely evolve LSS MMN phenotype, when distinctive long-term, focal, benign course.