The extent of damage of the islets of Langerhans in patients with chronic pancreatitis determines the severity and therapeutic consequences of diabetes. In 23 men with chronic pancreatitis, persisting for more than 10 years and diabetes, in the oral glucose tolerance test in serum the following were assessed: C peptide, glucagon and glucose-dependent insulinotropic polypeptide (GIP).Twelve patients were treated with insulin and had HbA1C 8.9 ± 1.9 %, 11 had no insulin treatment and HbA1C 7.4 ± 1.3 % (p < 0.05). In both groups the C-peptide secretion was reduced as compared with 10 healthy male controls (p < 0.001), but responded by a delayed rise after glucose administration. Contrary to controls, there was a paradoxical increase of serum glucagon in the patients after glucose administration. The GIP activities increased significantly after glucose administration in healthy subjects as well as in patients but it was not possible to prove an insulinotropic effect. The authors conclude from these data that insulin substitution is not always indispensible when there is a residual C-peptide secretion in patients with chronic pancreatitis and diabetes and that the risk of hypoglycaemia is not always increased. The impact of GIP secretion in these patients is not clear.

        Key words: diabetes – chronic pancreatitis – C-peptide – glucagon – GIP