Clinical Reasoning: A 64-Year-Old Man With Multiple Cranial Neuropathies

A 48-year-old man with hypertension, hyperlipidemia, and hypothyroidism presented to an outside institution progressive bilateral lower extremity numbness weakness. Nerve conduction studies (NCS) suggested acquired demyelinating polyneuropathy. Right sural nerve biopsy revealed mild chronic neuropathy, axonal degeneration, demyelination, remyelination. He received monthly IV immunoglobulin (IVIg) mycophenolate mofetil for a year. Due worsening symptoms in the setting of lengthened IVIg dosing intervals, repeat NCS were obtained showed disease progression. Monthly infusions resumed 8 years, during which his clinical electrophysiologic findings stabilized. Treatment was subsequently stopped, he initially remained neurologically stable off therapy.