[Stroke of unusual origin].
INTRODUCTION: Stroke of unusual origin is a heterogeneous syndrome with a number of different aetiologies. Most patients who are affected are young adults and it is often the first manifestation of a systemic disease. DEVELOPMENT: This type of stroke accounts for less than 10% of all ischemic strokes. Among its multiple aetiologies, cardioembolic and haematological diseases with a tendency toward hypocoagulability and dissections of the cervico encephalic arteries are the most common. The prognosis depends on the underlying aetiology but generally speaking this kind of stroke has a better prognosis than that of other types. CONCLUSIONS: Stroke of unusual origin is relatively rare, but nevertheless it deserves special attention since it affects young people above all, although its prognosis and treatment vary according to the aetiology. Exhaustive research needs to be conducted on these patients to establish the aetiological diagnosis and an early treatment