Granulomatosis with Polyangiitis Presenting as Ischaemic Stroke

Abstract

A 59-year-old man presented with symptoms of intermittent nasal obstruction and reduced hearing. He had a history of type II diabetes mellitus, managed with oral hypoglycaemic agents with no evidence of diabetic complications. He also reported well-controlled hypertension. There was no personal or family history of cardiovascular disease. Biopsies of the nasal mucosa showed evidence of vasculitis with fibrinoid changes within the vessels and endarteritis obliterans, in keeping with a diagnosis of GPA. Arthralgia and non-visible haematuria were noted and he was commenced on prednisolone 40 mg daily. Six days later, he presented to his local hospital with acute onset of left-sided weakness without higher level dysfunction in keeping with a right-sided lacunar infarct. Computed tomography of his head and carotid dopplers were both normal. He was treated with high-dose aspirin (300 mg daily) and dipyridamole. However, he was noted to have an elevated creatinine at 191 μmol/L which did not settle with discontinuation of his antihypertensive agents. Six months prior to presentation his renal function was normal. He was therefore transferred to our nephrology centre for further management. On admission he had persistent mild left-sided limb and facial weakness. His arthralgia had settled on low dose steroids and he denied pulmonary symptoms. His chest X-ray was clear and there was no vasculitic rash. Urine microscopy showed RBC casts and antineutro-phil cytoplasmic antibody (ANCA) was strongly positive (1:320 titre). A diagnosis was made of GPA with renal and nervous system involvement and he was commenced on cyclophosphamide 2 mg/kg daily and prednisolone 60 mg daily. In view of his persistent neurological signs, he was commenced on plasma exchange for presumed cerebral vasculitis. Magnetic resonance imaging (MRI) of his head (with gadolinium contrast) showed small areas of acute cortical infarction with bilateral enhancement but particularly in right parietal/occipital area (Figure 1). The intracranial vasculature appeared normal. The nature and distribution of the infarcts favoured a vasculitic cause for the patient's symptoms and signs. The patient's symptoms of weakness improved rapidly with this treatment, as did his creatinine which on discharge was 129 μmol/L. He completed 7 sessions of plasma exchange. By one month post discharge his creatinine had settled to his pre-morbid level of function with falling ANCA titres and continued clinical improvement in his limb and facial weakness.