Symmetric polyneuropathy after viral symptomatology - not always Guillain-Barré Syndrome

Introduction: Guillain-Barré Syndrome usually presents with ascending symmetric polyneuropathy, typically preceded by a viral infection. Despite the low incidence, physicians will often include Guillain-Barré Syndrome in their differential diagnosis. However, another underlying cause of polyneuropathy known as ANCA-associated vasculitis (AAV) is even more rare than Guillain-Barré Syndrome and therefore is usually overlooked. AAV has a broad spectrum of symptomatology and sometimes presents only with neurological complaints. If treated inappropriately, AAV can be lethal.Case report: In this case report, we describe a 72-year-old man presenting with complaints of symmetric polyneuropathy and paresis of both legs, initially diagnosed as Guillain-Barré Syndrome. During his treatment with intravenous immunoglobulins, he developed acute renal failure. Further investigations showed ANCA positive pauci-immune acute glomerulonephritis. This, in combination with eosinophilia and sinusitis, led to a final diagnosis of Eosinophilic Granulomatosis with Polyangiitis EGPA (Churg-Strauss disease). Induction therapy was initiated using glucocorticoids, cyclophosphamide and temporary plasmapheresis, followed by maintenance therapy with azathioprine complicated by bone marrow suppression. Azathioprine was discontinued and monotherapy with low-dose glucocorticoids was continued with the recovery of bone marrow function, good clinical condition and no relapse of vasculitis at 14 months follow-up.Conclusion: Physicians should be aware of the possible presentations of AAV. When suspected, indirect immunofluorescence assay for ANCA should be performed. When AAV is diagnosed, induction therapy should be administered as soon as possible, followed by maintenance therapy and careful follow-up, as patients are at risk for opportunistic infections, bone marrow toxicity or relapse.