Mystery of a cryptogenic stroke solved by an abdominal angiogram.

Despite advances in the field of imaging and diagnostics, the incidence of cryptogenic stroke is still around 30-40% in modern stroke databases. Our patient presented with recurrent midbrain infarcts over 3 years and was initially labelled as a patient with cryptogenic stroke. His blood investigations were normal, work up for autoimmune disorders was negative, CT brain angiogram was normal and a two-dimensional echo showed a small patent foramen ovale with a left to right shunt. He later presented with a right perinephric haematoma and an abdominal angiogram revealed multiple microaneurysms of the renal arteries, coeliac trunk and the mesenteric arterial system. The feeding renal artery was embolised. A diagnosis of polyarteritis nodosa was made. The patient was subjected to digital subtraction angiography of neck and intracranial vessels, which revealed multiple microaneurysms in internal and external carotid artery territory. He was discharged with steroids and azathioprine.