Granulomatous angiitis (GANS) of the CNS is a rare, idiopathic vasculitis confined largely to the small blood vessels of the CNS. It has also been referred to as “isolated”,1“primary”, and “idiopathic”2 angiitis of the nervous system. Clinical manifestations are usually the result of multifocal ischaemia and infarction and patients with GANS typically present with a chronic and relapsing but ultimately progressive encephalopathy, characterised by cognitive impairment and multifocal deficits. Less commonly, haemorrhage can occur as a result of infarction, focal necrosis of a vessel wall, or aneurysm rupture and the presentation may therefore be primarily neurosurgical.3 4 It is important to recognise this condition because long term clinical remission is possible with immunotherapy. In this letter we present a case which serves as a reminder to neurosurgeons to include GANS in the differential diagnosis of spontaneous intracerebral haemorrhage and emphasises the importance of leptomeningeal biopsy.

A forty six year old woman was admitted to our unit with a 24 hour history of confusion, vomiting, dysphasia, and a generalised seizure. The patient also had a 30 month history of deteriorating work performance and had had episodes of nausea, vertigo, and headache lasting 1 to 2 days. …