[Scintigraphic assessment of the severity of inflammatory bowel disease using Tc 99m exametazime-labeled leukocytes]

The aim of the work was to value the utility of semiquantitative scintigraphics indexes (GI) as predictive factor of activity grade of intestinal inflammatory process in patients with confirmed diagnosis of inflammatory bowel disease (IBD). 64 patients have been studied (39 males and 25 females), mean age was 40,2 years (range: 18-88 years) with diagnosis of IBD in acute exacerbation confirmed by endoscopy and biopsy. In all patients was obtained abdominal scintigraphy with 99mTc-exametazine labelled leukocytes. The severity of intestinal inflammatory process was quantified using clinical indexes -Truelove-Witts index (TI) for ulcerative colitis (UC) and Crohn's disease activity index (CDAI), Harvey index (HI) for Crohn disease (CD)-, endoscopic index (EI) and haematological parameters: erythrocyte sedimentation rate (ESR), hematocrit, haemoglobin, leukocyte and platelet count, fibrinogen and albumin level. In all the scans regions of interest were drawn over liver, spleen, bone, abdominal background and positive intestinal segments. Subsequently three GI were calculated: GI1, GI2 and GI3 for the scans obtained at 30 min (P) and 3 h p.i. (T). The evaluation of UC severity showed significant correlation between: 1) The GI1 P and T and TI, EI, ESR, leukocyte and platelet count; 2) The GI2 P and TI and EI; 3) The IG2 T and EI, hematocrit and platelet count; 4) The GI3 P and TI, EI, ESR and platelet count; 5) The GI3 T and TI, EI, leukocytes and platelet count. In the evaluation of CD was observed significant correlation between the GI1 P and GI3 P with the CDAI and EI, between the GI1 T and the GI3 T with the CDAI and ESR; the GI2 did not show significant correlation with any of the valorised parameters. In conclusion, the scintigraphic activity indexes based in the semiquantitative evaluation of scans obtained with 99mTc-exametazine labelled leukocytes showed usefulness in the evaluation of the IBD severity, especially in the UC. Among the studied indexes, IG1 seems the more accurate.