Hypertrophic nerves producing myelopathy in fulminant CIDP

A 59-year-old man died following a 20-year history of fulminant chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). His symptoms began with gait unsteadiness and ascending severe weakness and paresthesias, followed by papilledema and compressive cervical myelopathy from hypertrophic nerve roots (figure). Initial aggressive immunotherapy resulted in a return to ambulation and employment (previously reported as case 1).¹ Years later, he became quadriplegic due to a combination of immunotherapy-resistant CIDP (including cyclophosphamide) and consequent worsening cervical myelopathy. Varied extent and type of immune mechanisms in CIDP are inferred by such treatment-refractory patients.²

Figure pertrophic nerves in chronic inflammatory demyelinating polyradiculoneuropathy

(A) Sagittal and (B) parasagittal T2-weighted MRI of the cervical spine demonstrating hypertrophic nerve roots (arrows). (C) Cervical spine at autopsy showing compression from intradural hypertrophic nerve roots (arrowheads). Cervical nerve root histopathology with onion bulb formation on (D) methylene blue semithin epoxy sections and (E) Schwann cell (S-100) immunostaining.

1 Midroni G, Dyck PJ. Chronic inflammatory demyelinating polyradiculoneuropathy: unusual clinical features and therapeutic responses. Neurology 1996;46:1206–1212.

2 Pytel P, Rezania K, Soliven B, Frank J, Wollmann R. Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) with hypertrophic spinal radiculopathy mimicking neurofibromatosis. Acta Neuropathol 2003;105:185–188.