[Breath analysis tests in gastrointestinal disorders (author's transl)].

From various breath tests up to now mainly measurement of respiratory 14CO2 and hydrogen have attained clinical application. Breath tests are easily performable, without discomfort for patient or in investigator and do hardly require active support of the patient. On the other hand absorption tests, as 14C-tripalmitate- and 14C-lactose-breath test, are influenced by alterations of the metabolism in a considerable degree, and clinical significance and specificity of the 14C-cholylcycline-breath test remains questionable hitherto. Nevertheless, obtained values which are independent from metabolism, high sensitivity and lack of competitive methods are arguments for the 14C-cholylglycinebreth test for the diagnosis of bacterial overgrowth in the small bowel. Breath analysis of hydrogen seems to be a very sensitive and reliable method for detecting carbohydrate malabsorption, as lactose intolerance.