Comparison between the lactulose/mannitol and 51Cr-ethylenediaminetetraacetic acid/14C-mannitol methods for intestinal permeability. Frequency distribution pattern and variability of markers and marker ratios in healthy subjects.
Urinary excretion of lactulose and mannitol, determined by gas-liquid chromatography, was compared with that of 51Cr-ethylenediaminetetraacetic acid (EDTA) and 14C-mannitol for measurement of intestinal permeability in 28 healthy humans. The 0- to 6-h excretion values for unlabelled and labelled mannitol (marker of transcellular permeability) were normally distributed, whereas excretion values for lactulose and 51Cr-EDTA (markers of paracellular permeability) were skewly distributed, as were the lactulose to mannitol and 51Cr-EDTA to 14C-mannitol ratios. Excretion of the transcellular markers but not of the paracellular markers was significantly correlated to urinary volume; correction for urinary volume resulted in decreased test variability. Significant correlation was found between lactulose and 51Cr-EDTA excretion (p < 0.01) and between mannitol and 14C-mannitol excretion (p < 0.001) but not between the lactulose to mannitol and 51Cr-EDTA to 14C-mannitol ratios (p = 0.11). Inter- and intraindividual test variability was greater for each chemically determined marker than for the corresponding isotope-labelled marker. Similarly, variability was greater for each paracellular marker than for the corresponding transcellular marker and for each paracellular/transcellular marker ratio than for the transcellular marker alone. Variability of mannitol excretion was increased by the frequent presence of food-derived mannitol in the urine.
Blomquist
L
L
Dept. of Internal Medicine, Karolinska Hospital, Stockholm, Sweden.
Bark
T
T
Hedenborg
G
G
Svenberg
T
T
Norman
A
A
D000328:Adult; D000368:Aged; D002250:Carbon Radioisotopes / Q000652:urine; D002860:Chromium Radioisotopes / Q000652:urine; D004492:Edetic Acid; D005260:Female; D006801:Humans; D007408:Intestinal Absorption; D007413:Intestinal Mucosa / Q000378:metabolism*; D007792:Lactulose / Q000652:urine; D008297:Male; D008353:Mannitol / Q000652:urine; D008875:Middle Aged; D010539:Permeability
D002250:Carbon Radioisotopes; D002860:Chromium Radioisotopes; D008353:Mannitol; D007792:Lactulose; D004492:Edetic Acid