Diagnosis of intra abdominal inflammatory processes with 111In-labelled leucocytes

Over a two and a half year period, 225 scintigrams with indium-111 oxinate labelled leukocytes were performed in 184 patients suspected of an intra-abdominal, retroperitoneal or pelvic inflammatory process. In patients suspected of an upper abdominal process, an indium-111 leukocyte-99Tc-Sn colloid subtraction was performed, in order to eliminate the normal liver and spleen uptake. 123 Scintigrams were considered true positive and 73 true negative. A diagnostic accuracy of 87% was calculated. With 18 false-positive scans an 80%-specificity and with 11 false-negative a 92%-sensitivity were obtained. False-positive results in the majority of the scintigrams were based on leukocyte accumulations, due to aspecific cellular inflammatory reactions. False-negative results were mainly related to intra-hepatic, intra-splenic or older lesions. In 150 patients, ultrasonography and/or computed tomography was also performed. A higher diagnostic accuracy was observed with leukocyte scintigraphy compared to ultrasonography. (Auth.)