[Gastrointestinal hemorrhage of unknown origin]

Among 174 patients admitted for acute gastrointestinal bleeding the source of bleeding remained undetermined in 19 (10.9%) despite standard diagnostic workup. We show that an unknown source of acute gastrointestinal bleeding is not a risk factor with regard to the in-hospital outcome: there was no difference in the number of in-hospital days, of PRBC transfused or of surgical interventions; none of these patients died. While patient characteristics regarding mean age and sex distribution likewise did not differ, there was a significantly higher percentage of patients on NSAIDs or oral anticoagulants among those whose source of bleeding could not be found (80 vs 42%; p = 0.002). The clinical follow-up of the patients with undetermined source of bleeding reveals gastrointestinal pathology in a considerable proportion (18%); it calls for close follow-up of these patients after discharge.