EXOCRINE PANCREATIC INSUFFICIENCY - ACCURACY AND CLINICAL-VALUE OF THE UNIFORMLY LABELED C-13-HIOLEIN BREATH TEST

Background and Aims-The C-13-Hiolein breath test (98% [U-C-13] labelle d long chain triglyceride mixture (highly labelled triolein) was evalu ated as a non-invasive, non-radioactive test for exocrine insufficienc y. Accuracy validity were examined reference to both the secretin panc reozymin test and faecal fat analysis. Methods-A secretin pancreozymin test and faecal fat analysis were performed in 46 patients, 30 with e xocrine pancreatic insufficiency and pancreatic function. In all of th ese patients and in seven healthy volunteers (controls), a C-13-Hiolei n breath test was performed using 2 mg/kg [U-C-13] labelled Hiolein wi th a standard rice snack (1 . 5 g/kg; 25% fat). (CO2)-C-13/(CO2)-C-12 enrichment in the exhaled breath was measured by isotope ratio mass sp ectrometry. Results-In patients with pancreatic steatorrhoea the (CO2) -C-13 response was below the 95% confidence interval of (CO2)-C-13 exh alation in the controls. These responses were also diminished (p<0 . 0 01) compared with patients with impaired lipase output but normal fat excretion and with disease as well as healthy controls. There was a li near correlation between stimulated lipase output and the ratio of lip ase output/(CO2)-C-13 response (r=0 . 95). Among the 40 patients in wh om direct pancreatic function testing was clinically indicated, the se nsitivity of the C-13-Hiolein test for detecting steatorrhoea was 91 . 7%, with a specificity of 85 . 7%. Conclusions-In patients with pancr eatic disease the C-13-Hiolein breath test reflects impaired lipase ou tput and indicates decompensated lipolysis. The C-13-Hiolein breath te st is a convenient alternative to faecal fat analysis.