Cognitive dysfunction and decreased level of consciousness due to severe pneumocephalus in granulomatosis with polyangiitis.

Granulomatosis with polyangiitis (GPA) is a small-vessel vasculitis most commonly affecting the kidneys and respiratory tract. We report a case of a man in his 80s with known GPA presenting with gradually declining cognitive function over months, with sudden decreasing level of consciousness. A non-contrast CT of the head revealed severe pneumocephalus located in the left frontal lobe and in the ventricular system, due to erosion of the cribriform plate and a spontaneous dural perforation. The patient was immediately transferred to a neurosurgical department for insertion of an external ventricular drain. Surgical repair of the dural defect was subsequently performed through an endoscopic, endonasal approach using an autologous fascia lata graft. The patient gradually improved over the following days and had made a complete recovery 3 months after surgery.