The frequency with which florid duct lesions are seen in needle-biopsy spec
imens of the liver was assessed in patients with primary biliary cirrhosis
(PBC) enrolled in a 2-year randomized, double-blind, placebo-controlled tri
al of ursodeoxycholic acid (UDCA) versus placebo. Paired biopsy specimens o
btained at entry and after 2 years on medication were reviewed blindly and
mostly simultaneously by a panel of 5 hepatopathologists who, earlier, had
characterized the florid duct lesion, which has been well described in the
pathology literature. Florid duct lesions at entry were identified in appro
ximately 36%. Patients with earlier disease showed florid duct lesions much
more frequently than those with more advanced disease. The prevalence of f
lorid duct lesions in 60 patients receiving placebo medication fell from 38
.3% to 21.7%, P =.025, over the period of 2 years. The prevalence of florid
duct lesions also decreased in the 55 patients receiving UDCA, from 32.7%
to 18.2%, P =.046. The prevalences of these lesions in the placebo and UDCA
patients at entry and at 2 years were not significantly different from eac
h other. The findings suggest that UDCA does not prevent ongoing bile duct
destruction in patients with PBC. Instead, they support the impression that
UDCA exerts its beneficial effects by protecting against the consequences
of bile duct destruction.