Hypertrophic Pachymeningitis, Associated with Eosinophilic Granulomatosis with Polyangiitis, and ANCA-Negative Serology.

Background: Hypertrophic pachymeningitis (HP) is a disease with diverse aetiologies, including the autoimmune one, either associated with antineutrophil cytoplasmic antibodies or immunoglobulin G4.

Case Description: A 65-year-old woman with a history of systemic arterial hypertension, presented with intense progressive headaches. HP and hemispheric vasogenic oedema were observed by nuclear magnetic resonance (NMR) study.