Absorption of L-lysine diatrizoate from the gastrointestinal tract: the influence of surgery, inflammation and neoplasia

To ascertain whether the absorption of L-lysine diatrizoate, a sodium-free salt of the contrast-giving diatrizoic acid, from the gastrointestinal tract is increased by surgery, inflammation or neoplasia. Using contrast medium containing L-lysine diatrizoate for intestinal opacification, this prospective study compared 32 radiographic examinations of the upper gastrointestinal tract with 52 radiographic examination of the lower gastrointestinal tract. In blood samples taken from the patients immediately after the radiographic examinations, the concentration of diatrizoic acid was determined by high pressure liquid chromatography. The results were correlated with sex, age, surgical history and any evidence of inflammatory or neoplastic diseases. The serum diatrizoic acid concentration in patients after oral administration was 3.62 (95% CI, 2.86 - 10.17) microg/ml. The titer was lower in patients who had undergone abdominal surgery than in patients without surgery. Serum diatrizoic acid concentration in patients after rectal administration was 0.30 (95% CI, 0.13 - 0.60) microg/ml. The titer was significantly higher (p < 0.05) in patients suffering from inflammatory conditions or neoplasms than in the other patients. The L-lysine salt of diatrizoic acid is absorbed in larger amounts from the upper than from the lower gastrointestinal tract. Absorption is not increased after abdominal surgery. However, inflammatory conditions and neoplasms of the large bowel increase the uptake of contrast medium from the intestine.