[Diagnostic accuracy and clinical significance of combined small bowel enema and scintigraphy with pure fractions of neutrophil granulocytes labeled with HMPAO-Tc99m in chronic intestinal inflammation].

Enema is the primary imaging method in the diagnosis of Crohn's disease in the small bowel, with clinical follow-up examinations performed by gastroenterologists as the gold standard. The information provided by small bowel enema, in addition to endoscopic findings, is usually sufficient for the gastroenterologist to make the definitive diagnosis and to plan the whole treatment. Scintigraphy with leukocytes labelled with HMPAO-Tc99m has several unique characteristics favoring its use as a diagnostic imaging method in Crohn's disease and ulcerative colitis. It is a noninvasive method requiring no bowel preparation and it is safe in severely ill patients in whom such conventional imaging methods as barium enema or colonscopy might be hazardous. In this study, the authors report the results of their experience with diagnostic small bowel enema and leukocyte scintigraphy with HMPAO-Tc99m in 28 patients with inflammatory bowel disease (Crohn's disease in 18 patients, ulcerative colitis in 7 and radiation-induced inflammatory stenosis of the sigma-rectum, bowel inflammation after appendicectomy and bladder surgery, respectively, in 1 patient each). Scintigraphy with autologous granulocytes with HMPAO-Tc99m was positive in 26 patients and negative in 2. Twenty-five patients were true positives and 1 was a false positive. Fifteen patients were also submitted to small bowel enema: 12 of them were positive (true positive) and 3 negative (1 false negative and 2 true negative). The results of granulocytes scintigraphy were compared with those of small bowel enema: the radionuclide study appeared superior in the assessment of bowel inflammation associated with Crohn's disease and ulcerative colitis. Indeed, scintigraphy depicted granulocyte uptake in the colon where enema had shown no major findings in 4 patients with Crohn's disease. In the author's opinion, the overall sensitivity, specificity and positive predictive value of combined leukocyte scintigraphy and small bowel enema play a major role in the early diagnosis of Crohn's disease and ulcerative colitis and in the assessment of disease extent and activity.