Multiple nerve enlargements at non-entrapment sites are usually caused by hereditary or acquired immune-mediated neuropathies.We describe a case of multifocal hypertrophic mononeuropathies detected by nerve sonography with a clinical picture of progressive mononeuritis multiplex caused by a paraneoplastic syndrome associated with anti-Hu antibodies. This case illustrates an unusual but important paraneoplastic differential diagnosis of progressive multifocal hypertrophic neuropathies. It emphasizes the role of nerve ultrasound in the diagnostic work-up of peripheral nervous system disorders.
