Rapidly Progressive Paraneoplastic Neuropathy Associated with Renal Cell Carcinoma: A Case Report.

Background: Paraneoplastic neurological disorders are rare syndromes that occur with various malignancies including renal cell carcinoma. Symptoms of paraneoplastic neurological disorders are diverse and involve either the central nervous system, peripheral nervous system, or both.

Case presentation: We present a patient with diffuse limb pain, rapidly progressive asymmetric motor and sensory symptoms and distal upper limb atrophy. Electrodiagnostic testing was suggestive of mononeuritis multiplex. Initial empiric treatment with corticosteroids did not lead to improvement. Further diagnostic studies revealed bilateral clear cell renal carcinoma. Treatment with plasmapheresis led to significant and rapid improvement in pain and limb strength.

Conclusions: This case highlights the rare occurrence of paraneoplastic neuropathy in renal cancer and emphasizes the importance of screening for malignancy in patients presenting with rapidly progressive multifocal neuropathy.