A 50-year-old man with no prior medical history presented with rapidly progressive bilateral hand and foot weakness, distal sensory loss, and burning pain, more pronounced on the left side. Within one week, the weakness evolved in an asymmetric, stepwise pattern affecting all extremities. He also developed a non-pruritic purpuric rash with livedo reticularis, fever, night sweats, fatigue, and 10-pound unintentional weight loss. Neurologic examination revealed distal weakness (4/5), sensory ataxia, and diminished reflexes, with preserved coordination and gait.

Extensive laboratory testing ruled out infectious, hematologic, and autoimmune mimics. Nerve conduction studies showed an asymmetric distal axonal sensory-motor polyneuropathy consistent with MM. A nerve biopsy demonstrated ischemic and vasculitic changes, confirming small-vessel vasculitis. A concurrent skin biopsy showed thromboembolic coagulopathy and infarction.