Comparison of different endocrine stimulation tests in nondiabetic patients with chronic pancreatitis

The purpose of this study was to evaluate endocrine functional impairment in nondiabetic patients with chronic pancreatitis and to determine its reliability in the staging of this disease.

Eighteen patients with chronic pancreatitis and fasting normoglycemia (fasting blood glucose level < 100 mg/dl) and 10 healthy subjects underwent an oral glucose tolerance test (OGTT), an intravenous glucose test (IGT) and an arginine stimulation test (AST). Blood glucose and serum concentrations of insulin, C-peptide and glucagon were measured before and after stimulation. Exocrine pancreatic function was assessed by the pancreolauryl serum test (PLT), and morphological changes were staged by endoscopic retrograde pancreaticography (ERP), which were rated as I (mild), II (moderate) or III (severe).

Glucagon and C-peptide secretions after arginine stimulation were reduced in patients with moderate and severe chronic pancreatitis while no parameter was able to show impaired endocrine function in the early stage (ERP I) of the disease. Serum insulin concentrations proved to be of no use in the diagnosis of pathological B-cell function, since even patients with severe chronic pancreatitis and fasting normoglycemia demonstrated normal insulin secretion.

We conclude that there is a close correlation between morphological changes of the pancreas and functional endocrine reserve capacity, whereas endocrine stimulation tests were not shown to be helpful in the clinical assessment of nondiabetic patients with chronic pancreatitis.