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

OBJECTIVE

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, and neoplasia.

METHODS

The prospective study comprised 32 patients who were undergoing radiological examination of the upper gastrointestinal tract with a contrast medium containing L-lysine diatrizoate and 52 further patients who were undergoing examination of the lower gastrointestinal tract in the same way. The concentration of diatrizoic acid was determined by high-pressure liquid chromatography in blood samples taken before and immediately after the radiological examinations. The results were examined in terms of sex, age, surgical history, and any evidence of inflammatory or neoplastic diseases.

RESULTS

The serum diatrizoic acid concentration in patients tested after oral administration was 3.62 microg/ml. In patients who had undergone operation the titer was lower than in those who had not been operated on. Serum diatrizoic acid concentration in patients tested after rectal administration was 0.30 microg/ml. In patients suffering from inflammatory conditions or neoplasms the titer was significantly higher than in the other patients.

CONCLUSIONS

The L-lysine salt of diatrizoic acid is absorbed in larger amounts from the upper gastrointestinal tract than from the lower. Absorption is not increased after surgical operations on the viscera. However, inflammatory conditions and neoplasms involving the large bowel increase the uptake of the contrast medium from the intestine.