Teaching NeuroImages: Papilledema and Pachymeningitis: An Atypical Presentation of Granulomatosis With Polyangiitis.

A 53-year-old man presented with worsening headaches and progressive vision loss. His medical history was notable for biopsy-proven granulomatosis with polyangiitis (GPA), which was diagnosed after an episode of fever and hemoptysis years prior to the current presentation. Ophthalmologic examination was remarkable for bilateral papilledema (figure 1). Brain MRI with and without contrast demonstrated pachymeningitis and ventriculomegaly. Following ventriculoperitoneal shunt placement, there was resolution of headaches, papilledema, and ventriculomegaly (figure 2). The patient was subsequently treated with rituximab. Pachymeningitis—pathologic thickening of the dura mater—stands as a rare manifestation of GPA.1 The most common manifestation of pachymeningitis is cranial nerve paralysis, but it can also hinder venous sinus drainage and cause a communicating hydrocephalus.2