Folic acid absorption determined by a single stool sample test--a double-isotope technique. The folic acid absorption capacity in children.
The fractional folic acid absorption (FAFol) was determined in 66 patients with various gastrointestinal diseases by a double-isotope technique, employing a single stool sample test (SSST) as well as a complete stool collection. The age of the patients ranged from 2.5 months to 16.8 years (mean 6.3 years). The test dose was administered orally and consisted of 50 micrograms of [3H]folic acid (monoglutamate) (approximately 20 muCi), carmine powder, and 2 mg 51CrCl3 (approximately 1.25 muCi) as the unabsorbable tracer. The whole-body radiation given to a 1-year-old child averaged 4.8 mrad only. The stool and napkin contents were collected and homogenized by the addition of 300 ml chromium sulfuric acid. A 300-ml sample of the homogenized stool and napkin contents, as well as 300 ml chromium sulfuric acid (75% vol/vol) containing the standards, were counted for the content of 51Cr in a broad-based well counter. The quantity of [3H]folic acid was determined by liquid scintillation, after duplicate distillation. Estimated by SSST, the FAFol, which employs the stool with the highest content of 51Cr corresponding to the most carmine-colored stool, correlated closely with the FAFol based on complete stool collection (r = 0.96, n = 39, p less than 0.0001). The reproducibility of FAFol determined by SSST was assessed from repeated tests in 18 patients. For a mean of 81%, the SD was 4.6%, which corresponded to a coefficient of variation of 5.7%.(ABSTRACT TRUNCATED AT 250 WORDS)
Hjelt
K
K
Department of Pediatrics, University of Copenhagen, Gentofte Hospital, Hellerup, Denmark.
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D002860:Chromium Radioisotopes; D005243:Feces / Q000032:analysis*; D005492:Folic Acid / Q000032:analysis / Q000493:pharmacokinetics*; D006801:Humans; D007223:Infant; D007408:Intestinal Absorption; D014316:Tritium
D002860:Chromium Radioisotopes; D014316:Tritium; D005492:Folic Acid