[Aorto-duodenal fistula: endoscopic diagnosis]. / Fístula aorto-duodenal: diagnóstico endoscópico.

We report the case of a patient with hemorrhage due to secondary Aortoenteric Fistula (AEF), diagnosed by emergency oral endoscopy. We stress the importance of early diagnosis in these patients by virtue of a so-called "warning hemorrhage", which usually occurs hours or weeks before the appearance of a massive hemorrhage which is soon fatal. The importance of emergency endoscopy in the early diagnosis of these cases is emphasized.