Intestinal permeability of X-ray contrast media iodixanol and iohexol during bacterial overgrowth of small intestines in rats

To investigate the recovery of iodinated water-soluble contrast medium from small bowel with small morphological alterations, iohexol or iodixanol was instilled through an orogastric tube in rats 14 days after surgery that established a self-filling blind loop in the jejunum. This rat model induced small bowel bacterial overgrowth with only minor abnormalities observed on histology and scanning electron microscopy. Animals with end-to-end anastomosis of the jejunum or unoperated rats served as controls. Compared with unoperated animals, urinary recovery of iohexol and iodixanol was significantly higher in both groups that underwent surgery. Moreover, the contrast medium recovery was numerically higher in the self-filling blind loop group given iodixanol than in the end-to-end anastomosis group, although not statistically significant, P = 0.09. Our results indicate that iohexol and iodixanol may detect small barrier impairments in the intestines. Iodixanol, the largest of the two, may seem to differentiate better between normal and minimally impaired intestinal barrier.