Risk evaluation of postvagotomy ulcer recurrence by using endoscopic Congo red test and gastric secretion tests

To evaluate the usefulness of the endoscopic Congo red test (ECRT), and to compare sensitivity and specificity of different tests in the discrimination of cases with high risk for postvagotomy recurrent ulcer (RU).

In 271 consecutive postvagotomy duodenal ulcer patients the endoscopic Congo red test (ECRT) was used 5-12 years after vagotomy. Further, 39 patients out of 271 were selected and classified into two groups: A--13 ECRT positive cases with RU, B--26 controls without RU (13 ECRT positive and 13 ECRT negative cases). Basal acid output (BAO), maximal acid output (MAO), and nocturnal acid output (NAO) were determined pre- and postoperatively, the serum pepsinogen I (S-PGI) and insulin test were estimated postoperatively.

Positive ECRT had 95% sensitivity and 53% specificity for RU. S-PGI > 150 microg/l had 54% sensitivity and 92% specificity (in ECRT positive cases 100% specificity). The insulin test showed 83% sensitivity and 78% specificity. The respective data for the combination of BAO > 1.5 mmol/h + NAO > 30 mmol/12 h were 80% and 81%.

ECRT should be a primary step in estimating postvagotomy ulcer risk. In negative ECRT cases, the development of recurrent ulcer is unlikely. Additional gastric secretion studies as S-PGI or BAO+NAO or insulin test are needed only in ECRT positive cases.