RELATIVE SENSITIVITY OF TC-99M WBC VERSUS IN-111 WBC IN A PATIENT WITH CROHN-DISEASE AND STEROID USE

Numerous studies have shown that chemotaxis is affected by certain ant ibiotics and steroids. The authors present the case of a patient with Crohn disease relapse with multiple small-bowel fistulae and mesenteri c abscesses. Whereas the Tc-99m WBC scan failed to show the intra-abdo minal inflammatory foci, an In-111 WBC scan performed within a week de lineated the abscesses very well, and these were later confirmed at su rgery. This case is presented not only to illustrate the relative sens itivities of a Tc-99m WBC versus an In-111 WBC scan, but also to discu ss the impediment to polymorphonuclear chemotaxis by steroids, which m ay be a contributory factor to the sensitivities of the different radi opharmaceuticals selected for detection of intra-abdominal septic foci .