European Journal of Case Reports in Internal Medicine
Sudden bilateral blindness revealing MPO-ANCA-associated hypertrophic pachymeningitis in an 82-year-old woman
By Daniela Duque Montoya, Luis Felipe Aguirre García, Angélica María Vallejo Portilla and 2 others.
Abstract
Introduction
Hypertrophic pachymeningitis is a rare inflammatory thickening of the dura mater, complicating an estimated 1–3% of ANCA-associated vasculitis (AAV), usually PR3-ANCA disease with systemic involvement. Isolated meningeal disease with normal inflammatory markers is exceptional and easily mistaken for a non-inflammatory or ischaemic optic neuropathy.
Case description
An independent 82-year-old woman presented with 48 hours of bilateral visual loss after nine days of severe, non-postural occipital headache. She had no light perception, non-reactive pupils and optic disc pallor, without renal, pulmonary, cutaneous or sinonasal manifestations. Chest computed tomography, erythrocyte sedimentation rate and creatinine were normal. Contrast-enhanced magnetic resonance imaging showed diffuse pachymeningeal thickening with intense dural enhancement. Cerebrospinal fluid was acellular, with elevated protein and negative microbiology, including two Mycobacterium tuberculosis PCR assays. Anti-MPO exceeded 400 RU/ml, with negative anti-PR3, low C3 and C4, and normal IgG4, consistent with microscopic polyangiitis. Intravenous methylprednisolone 500 mg/day, started four days after blindness onset, was followed by recovery to counting fingers at 30 cm in the right eye by day 9.