FECAL C-13 ANALYSIS FOR THE DETECTION AND QUANTITATION OF INTESTINAL MALABSORPTION - LIMITS OF DETECTION AND APPLICATION TO DISORDERS OF INTESTINAL CHOLYLGLYCINE METABOLISM

  • 1 January 1981
    • journal article
    • research article
    • Vol. 97  (3) , 439-448
Abstract
The use of 14CO2 breath tests and fecal analyses for the detection and quantitation of intestinal malabsorption was extensively documented in adult subjects. The use of stable isotopes has extended the range of breath test applications to include pediatric and obstetric subjects. A fecal 13C analysis that can be used in conjunction with 13CO2 breath tests is reported. Twenty-four h fecal samples were collected before and after the administration of a labeled substrate. The samples were homogenized and combusted to CO2 and the 13C abundance was determined by high-precision, differential isotope ratio mass spectrometry. The isotopic variation between successive 24 h fecal samples was 0.6% (0.0006 atom %). This variation limited the sensitivity of the fecal analysis to 13 .mu.mol of 13C label/m of fecal C. Cholyglycine 13CO2 breath tests and fecal assays were simultaneously performed in 5 children. One child with bacterial overgrowth had an abnormal breath test and a normal fecal test. Of 3 children with ileal dysfunction, only 1 had an abnormal breath test, whereas the fecal test was abnormal in all 3. The breath test and fecal test were abnormal for a child who had undergone an ileal resection. Both tests were normal for a child with ulcerative colitis.