Lack of accuracy of plasma alpha-amino nitrogen profiles as an indicator of exocrine pancreatic function both after continuous and bolus stimulation of the pancreas with secretin and cholecystokinin-pancreozymin.

BACKGROUND: The reduced decrease of plasma alpha-amino nitrogen after hormonal stimulation of the pancreas has been characterized as a valid and simple test of pancreatic function. Aim of this study was to reassess the clinical value of the alpha-amino nitrogen test and to evaluate the role of different modes of hormonal secretion. Therefore, we have investigated the relationship of plasma alpha-amino nitrogen responses and pancreatic secretion, stimulated by either bolus injection (n = 25) or continuous infusion (n = 32) of cholecystokinin-pancreozymin in patients with and without exocrine pancreatic insufficiency as determined by the secretin-pancreozymin test. Of the 57 patients referred to the secretin-pancreozymin-test, 18 had pancreatic insufficiency, each 9 in the group with continuous and bolus stimulation. RESULTS: Basal alpha-amino nitrogen concentrations were almost identical in patients with and without impaired pancreatic function (2.66 +/- 0.12 mmol/l vs. 2.73 +/- 0.08 mmol/l [SEM]; p > 0.05). Both, the bolus dose and infusion of cholecystokinin induced similar (log-normally distributed) maximum decreases of alpha-amino nitrogen concentrations (-SD; mean; + SD: 3.6; 9.0; 22.3% vs. 6.0; 10.5; 18.5%, respectively) in the patients without exocrine pancreatic insufficiency. This was in tendency more pronounced compared to those with impaired pancreatic secretion (cholecystokinin bolus; 2.7; 5.2; 9.9%; infusion: 5.0; 7.7; 11.6%). The difference (+/- exocrine pancreatic insufficiency) was significant (p < 0.05) for the infusion mode only. Moreover, the time course of alpha-amino nitrogen concentration-profiles was more homogenous after hormone infusion as compared to bolus stimulation. Sensitivities to detect exocrine pancreatic insufficiency by the alpha-amino nitrogen test were < 50% with either test modification. CONCLUSION: The decrease of plasma alpha-amino nitrogen after stimulation with cholecystokinin is no accurate indicator of exocrine pancreatic function, regardless of whether hormonal stimulation is by bolus or by infusion.

Chronic nausea as the leading symptom: an indication for double-contrast examination of the upper intestinal tract following normal gastroscopy.

We report a patient with chronic nausea as the leading symptom of a primary carcinoma of the duodenum located at the flexura duodeno-jejunalis. The tumour was not reached at gastroscopy, which was performed twice. Since this area usually cannot be seen upon gastroscopy or upon small bowel enteroclysma according to Sellink, a double-contrast investigation of the upper gastrointestinal tract using a hypotonic agent should be performed when nausea persists although gastroscopy is normal.