111-Indium labelled autologous leucocytes in diagnosis of inflammatory bowel disease

111-Indium labelled leucocytes have been used to visualize inflammatory lesions in ulcerative colitis (CU) and in Crohn's disease (CD). The aim of this study was to compare findings by scintigraphy, radiology and endoscopy. Material: Twelve patients with CU and 15 patients with CD were studied. All patients were non-febrile. Two patients received prednisolone 5 mg/daily, 8 sulphasalazine. Methods: Autologous leucocytes were labelled with 111-In-Oxine and given i.v. Scintigrams were obtained 3 and 24 hrs. p.i. Double contrast x-ray studies were done of the colon and small intestine after 2 and 14 days respectively. Colonscopy with biopsy was done after 4 days. Results: Active lesions were found in 24 and 27 patients. Scintigrams 24 hrs.p.i. did not give and additional information compared with scintigrams 3 hrs.p.i. Intraluminal activity masked the location and extension of lesions after 24 hrs. Excretion in the stool was 2.4-25.8% of administered activity. Compared with scintigraphy a corresponding extension and location was found by colonscopy. In 4 patients x-ray of the colon was normal but scintigraphy and colonscopy showed active inflammation. Conclusion: Scintigraphy after injection of 111-In labelled leucocytes is a atraumatic method for visualization of inflammatory lesions in UC and CD. Furthermore, it appears to be more sensitive than conventional x-ray studies