CLINICAL-VALUE OF LABELED RED-BLOOD-CELL SCINTIGRAPHY IN PATIENTS WITH DIFFICULT TO DIAGNOSE GASTROINTESTINAL-BLEEDING

A retrospective study was conducted using 36 patients with gastrointes tinal bleeding in whom the diagnosis was not directly apparent from fi rst line diagnostic procedures. Final diagnosis was established by sur gery, endoscopy, or postmortem examination in 20 patients. Scintigraph ic examination with Tc-99m or In-111 labeled red blood cells yielded 2 4 positive and 18 negative results. Nine out of 13 positive scans (ver ified by other diagnostic procedures) accurately identified the site o f bleeding. This was considered to be a satisfactory result in this gr oup of difficult to diagnose patients. The lowest success rate was obs erved in patients taking drugs that interfered with coagulation, or in patients prone to diffuse blood loss because of coagulopathy. Late sc ans did not offer additional information and the use of In-111 for thi s purpose was not thought to be of benefit. Although the technique is rather noninvasive and simple, its application should be restricted to selected patients and its interpretation related to the results of ot her investigations.