Impairment of secretin release in celiac sprue

Plasma secretin concentrations and pH in the second portion of duodenum were measured in the fasting state and during duodenal infusion of HCl in five patients with untreated celiac sprue, five celiac sprue patients after gluten-free diets, and five normal subjects. Mean fasting plasma secretin concentrations were insignificantly lower in untreated sprue patients (4.1 +/- 1.4 pg/ml) than in normal subjects (5.7 +/- 0.59 pg/ml). During 30-min intraduodenal infusions of 0.1 N HCl at 0.20 mEqH+/min, mean plasma secretin concentrations were significantly lower in untreated sprue patients (5.8 +/- 1.8 pg/ml) than in normal subjects (25.4 +/- 1.60 pg/ml, P less than 0.01). The increases in mean secretin concentrations over fasting were 2.1 +/- 0.82 pg/ml in untreated sprue patients compared to 19.7 +/- 1.47 pg/ml in normal subjects (P less than 0.01), a ninefold difference. The results indicate that endogenous release of secretin in response to duodenal acidification is impaired in patients with celiac sprue.