Cerebrovascular manifestations in Klippel-Trenaunay Syndrome (KTS) have been reported but are extremely rare. Case reports describe brain embolism in KTS-associated coagulopathy as well as bleeding due to arteriovenous malformations. We describe a 45-year-old patient with KTS and both acute ischemic stroke and repeated cerebral haemorrhage. The underlying aetiology of both events remained undetermined despite extensive diagnostic work-up, including coagulation tests and dynamic MR angiography. It is most likely that both a pathological coagulation and increased vessel fragility comparable to amyloid angiopathy were responsible for the combined brain lesions in this patient. We conclude that KTS is a very rare but relevant aetiology of cerebral ischemia and that anticoagulation treatment in these cases should be carefully considered as the risk of cerebral haemorrhage is probably elevated. (C) 2013 Elsevier Ltd. All rights reserved.