Intestinal bile salts in cystic fibrosis: studies in the patient and experimental animal.

The quantitative and qualitative distribution of bile salts in the duodenal juice 
of 13 patients with cystic fibrosis (CF) was studied after a 
test meal. The effects of triolein (TO), bovine serum albumin (BSA), 
and ricinoleic acid (RA) on the absorption of taurocholate (TCA) in 
the distal ileum of the rat in vivo was also studied. 
The mean (and ranges) of total bile salt concentrations, glycine: taurine 
conjugate ratios, and percentage of dihydroxy bile salts in the patients 
with CF and pancreatic insufficiency were 3.5 (1.3--6.6) mmol/l, 8.6 (greater 
than 10-3.1), and 37 (10--60) compared with control values of 7.4 
(3.0--16.0) mmol/l, 3.0 (1.3--4.5), and 61 (52-- 70) respectively. The differences 
between the control and CF values were statistically significant (P less 
than 0.01--P less than 0.001). Three of the 13 CF patients 
had total bile salt concentrations less than 2 mmol/l, 8 had 
much higher glycine: taurine ratios, and 8 had a reduced percentage 
of dihydroxy bile salts. In 2 patients with normal pancreatic enzyme 
activities, duodenal bile salts were both quantitatively and qualitatively normal. TO 
(10 and 30 mmol/l), BSA (3%), and RA (5 mmol/l) had 
no inhibitory effect on the ileal absorption of TCA. These results 
show pronounced abnormalities of duodenal juice bile salts in CF with 
pancreatic insufficiency consistent with a broken enterohepatic circulation (EHC); such abnormalities 
may contribute to defective lipid absorption in CF. The data in 
the experimental animal do not support the suggestion that unhydrolysed dietary 
substrates play a role in the pathophysiology of the broken EHC. 
