[Recurrent epistaxis of unknown origin. A rare differential diagnosis and its treatment].

We present the case report on a 66-year-old male patient who appeared in our clinic with recurrent epistaxis. Anterior rhinoscopy during acute bleeding yielded no information on the origin of hemorrhage. On renewed epistaxis, angiography was performed on which an arteriovenous malformation in the sphenoid sinus could be identified as the cause of epistaxis. Embolization of afferent vessels successfully reduced the malformation and stopped the bleeding. In cases of recurrent epistaxis, especially in combination with an unremarkable anterior rhinoscopy, angiography is recommended for the detection of life-threatening vessel malformations.