[Angiographic diagnosis in intestinal angiodysplasia. Series of 13 cases]

The authors report 13 cases of intestinal bleeding; while serials endoscopic and radiological examinations had been negative, arteriography allowed intestinal angiodysplasia to be diagnosed, and detected 18 lesions (12 of the right colon, 6 of the small bowel), confirming the fundamental role of arteriography in the diagnosis the localization and extension of these lesions. The importance of accuracy is emphasized both in the performance and in the evaluation of angiographic findings, in order to avoid missing multiple localizations (colon and small bowel). The authors illustrate and evaluate the different angiographic findings. Among these, the collection of contrast medium into parietal vascular lacunae and the early and dense opacification of the draining veins appear to be the most specific and frequent findings of angiodysplasia. In their series of patients the authors have also observed how the dilatation of the feeding artery, up to the antimesenteric side (a sign which is hardly ever reported in literature), was often present in the cecal localizations but could never be observed in the small bowel. Finally the surgical results and follow-up are considered.

[Intestinal angiodysplasias. Diagnostic and therapeutic problems]

The cases are presented of 9 patients with intestinal angiodysplasia observed in 1979-85 in the surgery departments of San Carlo Borromeo Hospital, Milan. Diagnostic problems are discussed with particular reference to angiographic and endoscopic methods. Surgical treatment gave good results. Recurrent bleeding may depend on the inadequate assessment of the extension of the lesion or on the existence of other unrecognised intestinal sites.

Tubular nephrotoxicity after intravenous urography with ionic high-osmolal and nonionic low-osmolal contrast media in patients with chronic renal insufficiency

Nephrotoxicity of intravenous contrast media is more frequent and striking in patients with risk factors, the major one being preexisting chronic renal insufficiency. New nonionic low-osmolal contrast media allegedly have less nephrotoxicity than the traditional ionic high-osmolal ones. This was tested for two contrast media in a group of 18 patients with stable chronic renal insufficiency. The urinary excretion of two brush-border enzymes (alanine aminopeptidase, AAP, and gamma-glutamyl transpeptidase, gamma-GT) and of a lysosomal enzyme (N-acetyl-beta glucosaminidase, NAG), functional markers of tubular injury, were measured before and after intravenous urography with an ionic high-osmolal radiocontrast medium, meglumine sodium diatrizoate, or with a non ionic low-osmolal one, iopamidol. Urinary NAG excretion did not change significantly after administration of either contrast media. Urinary AAP and gamma-GT excretion increased significantly (p less than 0.01) after diatrizoate. After iopamidol, only gamma-GT excretion increased significantly (p less than 0.05). Our data suggest that the nonionic low-osmolal radiocontrast medium iopamidol is less toxic to tubules than the ionic high-osmolal medium diatrizoate and that the brush-border enzymes AAP and gamma-GT are sensitive markers for this toxicity.

[Nephrotoxicity of contrast media. Comparison of iopamidol and diatrizoate by measurement of urinary enzymes after urography]

An ionic (diatrizoate) and a non ionic (iopamidole) radiocontrast medium were compared as to their nephrotoxicity in a cohort of 21 patients with renal disease, 18 of which with normal renal function. The elevation of the urinary excretion of enzymes from renal tubular cells has been considered as a good index for renal tubular damage. We measured two lysosomal enzymes (NAG and beta glucuronidase) and a brush-border enzyme (gamma GT). In all patients we demonstrated an elevation of urinary excretion of the three enzymes already 12 hours after contrast medium administration. However, the elevation was statistically significant only after employment of the ionic contrast medium and concerned gamma GT and beta-glucuronidase; the urinary excretion of NAG did not vary significantly. Urinary enzymes levels returned to basal values 36 hours after intravenous pyelography. In conclusion, iopamidole showed a lower nephrotoxicity with respect to diatrizoate, as demonstrated by the lower levels of urinary enzymes excretion reached after its use.