Common bile duct dilatation on MRI in autosomal dominant polycystic kidney disease.
Academic Article
Overview
abstract
PURPOSE: Polycystic liver disease is the most prevalent extrarenal manifestation of autosomal dominant polycystic kidney disease (ADPKD). Non-obstructive asymptomatic common bile duct (CBD) dilatation has been observed anecdotally on CT scans, but CT is not optimal for biliary visualization. Here, we measured CBD diameter on T2-weighted MRI in ADPKD subjects to determine if CBD dilatation is associated with ADPKD. METHODS: CBD diameter was measured retrospectively on ADPKD subjects (n = 254) and on age- and sex-matched controls without ADPKD (n = 254) who underwent abdominal MRI. CBD diameter in these groups was compared and correlated with clinical, laboratory and magnetic resonance imaging (MRI) features, including organ volumes and cyst burden. RESULTS: CBD median diameter [interquartile range, IQR, 25%, 75%] was 22% larger in ADPKD compared to controls (5.6 [4.7, 6.9] mm vs. 4.6 [3.9, 5.4] mm, p < 0.001). CBD diameter measurements had excellent inter-observer agreement (Intraclass correlation coefficient = 0.92). Thirteen (5.1%) ADPKD subjects had a CBD diameter ≥ 10 mm compared to 1 (0.4%) control subject (p < 0.001). Multivariable analysis found the presence of PKD1 or PKD2 mutation (beta = 1.5, P < 0.001) and age (beta = 0.04, p < 0.001) to be associated with increased CBD diameter and serum albumin associated with decreased CBD diameter (beta=-0.39, p < 0.001). CONCLUSION: ADPKD subjects had 22% larger CBD diameters than in non-ADPKD controls and were more likely to have CBD dilatation ≥ 10 mm without CBD obstruction. Awareness of this association of non-obstructive CBD dilatation with ADPKD may limit unnecessary diagnostic testing.
