Serum gastrin levels in the differential diagnosis of recurrent peptic ulceration due to retained gastric antrum.

If recurrent peptic ulceration follows partial gastrectomy with Billroth II reconstruction, retained antrum on the duodenal stump may be the culprit. Moderate hypergastrinemia and a high basal acid output (BAO) to maximal acid output (MAO) ratio on gastric analysis should alert the clinician. Careful filling of the afferent loop on barium meal or technetium 99m scanning may verify the diagnosis. The secretin provocative test may be helpful in distinguishing retained antrum from the Zollinger-Ellison syndrome by eliciting a decrease in serum gastrin levels in patients with retained antrum and an increase in serum gastrin levels in patients with Zollinger-Ellison syndrome.