Ulcerative colitis : Imaging of inflammation

Sammanfattning: Ulcerative colitis is a chronic inflannnatory disorder of unknown origin engaging the large bowel. Based on the need for accurate assessment of inflammation, three different non-invasive techniques, two leukocyte scintigraphy techniques and one radiological method, were evaluated in the assessment of active inflammation in altogether 131 patients with ulcerative colitis. Results were compared to those of endoscopy with biopsy, and with histopathological grading of depth of ulceration in colectomy specimens. Nine non-inflamed controls were also includedLeukoeyte scintigraphy using technetium-99m exarnetazime-labelled lenkocytes was found to reliably differ between patients with and without colonic inflammation. A good correlation existed between a simple visual scoring system of lenkocyte scans and colonic inflannnation viewed endoscopically and histologically in ulcerative colitis. In active disease, inflammation was better visualized with technetiurn-99m exametazimelabelled leukocytes than with technetium-99m anti-granulocyte antibody BW 250/183.Air enema radiology was of value in estimating severe mucosal inflammation in acute ulcerative colitis. Presence of faecal residue or a normal air enema film were associated with normal or only mildly inflamed mucosa at colonoscopy, i.e. a friable or ulcerated mucosa can be excluded. The absence of faecal residue or an abnormal finding at air enema X-ray were predictive of endoscopically inflamed mucosa. Air enema radiology underestimated the extent of inflannnation compared to endoscopy or lenkocyte scintigraphy. Air enema radiology was able to demonstrate presence of deep histopathological ulceration in the colectomy specimens from patients with an acute attack of ulcerative colitis.In conclusion, scintigraphy with technetium-99m exarnetazime-labelled lenkocytes can be applied in excluding or confirming bowel inflammation in individual patients, and, in assessing intensity and extent of ulcerative colitis. Air enema radiology should be a first-line investigation in acute colitis to assess the presence of mucosal or deeper ulceration.