Abnormal duodenal [HCO3-] following secretin stimulation develops sooner than endocrine insufficiency in minimal...

Direct pancreatic function tests (PFTs) are often used to diagnose chronic pancreatitis (CP). We aimed to determine the temporal relationship between an abnormal PFT result, cross-sectional imaging, and clinical symptoms.

All patients referred for endoscopic ultrasound (EUS) and PFT for suspected CP at our medical center from 2008 to 2010 were included. Each subject underwent EUS and PFT on the same day using secretin stimulation.

Seventeen patients had duodenal HCO3 values of less than 80 mEq/L and were labeled as abnormal; the 25 other patients had at least 1 duodenal HCO3 values of 80 mEq/L or greater. Patients with abnormal PFTs had more parenchymal (2.0 vs 0.92, P = 0.012), ductal (1.18 vs 0.6, P = 0.036), and total features (3.18 vs 1.52, P = 0.009) than those with normal PFTs on EUS examination. There was no difference in regard to the frequency of abnormal CT scans (25% vs 15%, P = 0.139), diarrhea (67% vs 60%, P = 0.463), fat-soluble vitamin deficiency (33% vs 26%, P = 0.315), or diabetes (10% vs 4%, P = 0.066).

Patients with equivocal imaging and abnormally low duodenal HCO3 have more EUS features of CP than do patients with normal duodenal HCO3 values, suggesting that low duodenal HCO3 values are among the first measurable abnormalities in CP.