Neurolymphomatosis presenting as mononeuritis multiplex.

We report the case of a 60-year-old man who presented with a mononeuritis multiplex-type illness, beginning cranially and then sequentially involving peripheral nerves in all four limbs and torso. Despite extensive investigation, including multiple lumbar punctures and tissue biopsies, the diagnosis was not made until his death 10 months after presentation. Post mortem revealed lymphocytic infiltration of multiple peripheral nerves and radicules with minimal central nervous system involvement, consistent with neurolymphomatosis. Except for the pericardium, there was no other evidence of systemic lymphoma. Recent similar case reports highlight the value of magnetic resonance imaging of plexi and peripheral nerves, which may increase the chance of an antemortem diagnosis in this typically elusive disorder.