Eosinophilic Granulomatosis with Polyangiitis Presenting as Acute Polyneuropathy Mimicking Guillain-Barre Syndrome.

Eosinophilic granulomatosis with polyangiitis (EGPA) is a small-vessel vasculitis associated with antineutrophil cytoplasmic antibodies (ANCAs) which commonly affects the peripheral nervous system. A 38-year-old female with a history of asthma presented with a 2-week history of bilateral lower extremity paresthesias that progressed to symmetric ascending paralysis. Nerve conduction studies could not rule out Guillain-Barre syndrome (GBS) and plasmapheresis was considered. Her blood work revealed marked eosinophilia (>50%), she had purpuric lesions in her legs, and a head magnetic resonance image showed evidence of pansinusitis. Coupled with a history of asthma we suspected EGPA-associated neuropathy and started steroid treatment. The patient showed rapid and significant improvement. ANCAs were later reported positive. ANCA-associated vasculitides present most often as mononeuritis multiplex, but they can mimic GBS and should always be considered in the differential diagnosis, since the treatment strategies for these conditions are radically different.