Experimental Colonic Inflammation and Ulceration: Permeation of a Water-Soluble Contrast Medium as a Measure of ‘Disease’ Activity

Abstract

The aim of this study was to investigate the permeation of an isosmolar water-soluble X-ray contrast medium (CM) from the unperforated colon after experimental induction of inflammation and ulceration. One hundred and sixty-five male rats were included. In 110 rats 0.25 ml of 40% ethanol + 15 mg or 30 mg trinitrobenzene (TNB) was instilled into the colon, 7-9 cm proximal to the anus, inducing different degrees of inflammation. Fifty-five rats served as controls and had 0.25 ml saline instilled with the same procedure. At 7, 14, 21, and 28 days 3 ml of the non-ionic CM iodixanol was applied as an enema, and subsequently all urine was collected for the next 4 h. High-performance liquid chromatography analyses of the urine showed a positive relation between the severity of inflammation/ulceration in the colonic wall as assessed by a macroscopic damage score and the amount of CM excreted in the urine. Water-soluble contrast media may have prospects of combining functional tests of intestinal membrane dysfunction with segmental exposure control.

Urinary Excretion of Iohexol as a Marker of Disease Activity in Patients with Inflammatory Bowel Disease

“…Urinary excretion of iohexol correlates positively with clinical activity indices and with extent of active disease, but it was on the same low level in patients in remission and in healthy controls. This finding differs from previous data of permeability tests with large sugar molecules, in which permeation has been increased in all patients with Crohn's disease irrespective of activity stage (1)(2)(3)(4), but some authors have found correlation between permeation of the probe and activity of the disease In rats with experimental colitis permeation of watersoluble contrast medium has been found to correlate with 'disease' activity (6) and with the permeation of 5'Cr-EDTA (7). Furthermore, investigations performed in rats have shown that urinary excretion of water-soluble contrast media is increased in bowel ischemia and after selective irradiation of the small bowel but not in simple bowel obstruction (15-17).…”

“…Patients (n = 12) and controls (n = 10) described in the pilot study (6) were included. The mean age of the patients was 38.0 ?…”

“…Most clinical studies have been permeability studies in relatives and patients, and fewer have evaluated the correlation between permeability and disease activity. On the other hand, in experimental colitis of rats increased mucosal permeability has been found to correlate with 'disease activity' (6,7 ) .…”

Diagnostic error due to vicarious excretion of rectal iodinated contrast

“…Colonic absorption is particularly pronounced in patients with a range of intestinal pathologies, such as inflamed bowel due to IBD and gastroenteritis, radiotherapy or diverticulitis 11 . Animal studies have confirmed a positive correlation between the length and severity of inflammation/ulceration in the colonic wall and the amount of contrast media excreted in urine 12,13 . Experimentally, water‐soluble contrast media have been used as intestinal permeability probes for detection and quantification of altered intestinal barrier function, as they offer the advantage of allowing direct control of bowel wall exposure using fluoroscopy 5 …”

Shark Fin Enriched Diet Prevents Mucosal Lipid Abnormalities in Experimental Acute Colitis

“…Then, according to the method described by Andersen et al [11], a watersoluble contrast medium (Iodixanol) was instilled into the colon. At the same time, the urinary bladder was cannulated, and the abdomen was closed.…”