Impaired glucose tolerance and diabetes mellitus (CFRD - cystic fibrosis related diabetes) are a frequent complication in patients with cystic fibrosis. Within the framework of CFRD screening the authors examined in 122 patients above the age of 10 years without clinical symptoms of diabetes mellitus the oral glucose tolerance test (oGTT). In subjects with a pathological oGTT subsequently the intravenous glucose tolerance test was made to assess stimulated insulin secretion (FPIR; sum of insulin levels during the 1st and 3rd minute after an i.v. glucose bolus). CFRD was diagnosed in 19/122 patients (15.6%), impaired glucose tolerance in 18/122 (14.8%). A total of 37/122 (30.3%) patients with impaired glucose tolerance or CFRD were diagnosed. Marked insulinopenia (FPIR < 48 mIU/l) was found in a total of 29/122 patients (23.8%), incl. 10/18 with impaired glucose tolerance. The finding of marked insulinopenia makes it possible also in patients with impaired glucose tolerance to select rationally individual therapeutic procedures.

        Key words: cystic fibrosis, diabetes mellitus, CFRD, impaired glucose tolerance, FPIR