Clinical relevance of intestinal barrier dysfunction in common gastrointestinal diseases

Table 1 Functional probes used to clinically assess bowel permeability in humans

Functional probe	Proposed test site	Sample site	Ref.
51Cr-EDTA	Whole intestine	Urine	Bjarnason et al[14], 1983
Lactulose/mannitol1	Small intestine	Plasma/urine	Rao et al[11], 2011
PEG400	Whole intestine	Urine	Ma et al[132], 1990
Sucralose2	Colon	Urine	Anderson et al[133], 2004
Sucrose2	Gastroduodenal	Urine	Meddings et al[134], 1993

¹Cellobiose and L-rhamnose have been used as alternatives to lactulose and mannitol, respectively.

²Usually in combination with lactulose/mannitol. ⁵¹Cr-EDTA: Chromium-51-ethylenediaminetetra-acetate.