Neurological impact of eosinophilic granulomatosis with polyangiitis.

Nervous system (NS) affection may occur in Eosinophilic Granulomatosis with Polyangiitis (EGPA), but its clinical manifestations and pathophysiology are rarely described. Our aims are to characterize central and peripheral NS (CNS/PNS) involvement and compare biological markers in EGPA patients with and without neurological manifestations. Retrospective observational study, including EGPA patients with and without neurological manifestations. Demographics, clinical data, and immunological markers were analyzed. Descriptive and inferential statistics were performed. Sixteen patients were included; 11 (68.8%) of whom were male, with a mean age of 63.38 years; 8 with (Group 1) and 8 without (Group 2) neurological findings. Neurological impairment preceded EGPA diagnosis in 5 patients, and occurred during follow-up in 3 patients after a median of 4.0 years. CNS manifestations observed were stroke (n = 2), bilateral central retinal artery occlusion (n = 1), and compressive dorsal myelopathy due to extradural granulation tissue (n = 1). PNS manifestations were axonal polyneuropathy (n = 3), sensorineural hearing loss (n = 3), and multiplex mononeuropathy (n = 1). Two patients had both PNS and CNS involvement. There were no statistical differences regarding biological markers [eosinophil count, myeloperoxidase (MPO) antibodies titers] between the 2 groups. One patient from Group 1 was unresponsive to treatment and permanent neurological sequelae were observed in 7 cases. EGPA-related NS involvement can be heterogeneous and is responsible for long-term sequelae. In our sample, the main neurological scenarios were peripheral neuropathy, VIII cranial nerve neuropathy, ischemic lesions and compressive myelopathy. Patients with and without neurological manifestations did not differ in eosinophilic count and MPO titer.