Background: An increased permeability to sugars is found in the intestine o
f untreated patients with coeliac disease after oral ingestion.
Aim: To test whether in vitro permeability resembles in vivo permeability t
ests and whether an in vitro gliadin gluten challenge could be performed by
an in vitro permeability test.
Methods: We measured in vivo (urinary excretion after sucrose-lactulose-man
nitol ingestion) and in vitro permeability (by mini-Ussing chambers) in 25
healthy controls, 12 relatives of coeliac disease patients, 19 treated, eig
ht partly treated and 16 untreated patients with coeliac disease.
Results: In vivo sugar permeability was increased in nearly all coeliac pat
ients. Additionally, in vitro permeability to lactulose (P = 0.0007), manni
tol (P = 0.004) and sucrose (P = 0.042) was higher in untreated patients wi
th coeliac disease. It correlated with in vivo permeability (sucrose tau =
0.61, P = 0.006; lactulose tau = 0.41, P < 0.0001; mannitol <tau> = 0.56, P
= 0.62) and was dependent on mucosal damage. An in vitro gliadin challenge
over 24 h could not significantly change in vitro permeability in treated
patients with coeliac disease.
Conclusions: An in vitro permeability test capable of measuring elevated pe
rmeability in coeliac mucosa was described, but this test cannot replace or
al gluten challenge by in vitro gliadin incubation.