Hypertrophy of the cauda equina nerve roots is a nonspecific finding and may be seen in hereditary and acquired demyelinating neuropathies or due to infiltration of the nerve roots by malignancy. We describe a patient with hypertrophy of the cauda equina nerve roots as a likely paraneoplastic phenomenon.
A 60-year-old man was seen for a 3-year history of progressive distal lower limb paresthesias. For 18 months before his evaluation, he had been symptomatic with gait difficulty that would increase in the dark. Walking for prolonged distances was accompanied by leg weakness, heaviness, and numbness, all of which would improve on sitting down. On examination, he had mild weakness of the distal aspect of the lower limb muscles with marked loss of vibration and moderate loss of position perception in the toes. Perception of light touch and pin prick were intact. His lower limb reflexes were absent, he had a flexor plantar response, and he had difficulty walking on his toes or heels. He had positive results for the Romberg sign. Nerve conduction studies showed evidence of a mild, length-dependent, axonal peripheral neuropathy. Somatosensory evoked potential studies were remarkable for impaired conduction in the central proprioceptive pathways below the cervical level. Cerebrospinal fluid analysis revealed a protein level of 0.138 g/dL (reference range, 0.014-0.045 g/dL), a normal glucose level, and absence of increased cellularity.
Kumar N, Dyck PJB. Hypertrophy of the Nerve Roots of the Cauda Equina as a Paraneoplastic Manifestation of Lymphoma. Arch Neurol. 2005;62(11):1776. doi:10.1001/archneur.62.11.1776