Hypogenesis of intramural vascularity and perivascular plexuses of gallbladder in patients with congenital biliary dilatation

Background

We hypothesized neuronal disorders of the biliary tract as the cause of congenital biliary dilation (CBD).

Methods

Gallbladders were removed from a total of 15 patients who were categorized into two study groups: a CBD group (eight patients) and in a control group (neuroblastoma, acute myelogenous leukemia, wandering gallbladder, Wilms’ tumor, glycogen storage disease, familial amyloid polyneuropathy; seven patients). Whole-mount preparations of the gallbladders were made to immunostain the intramural nerves.

Results

The intramural vascularity in the gallbladders of the CBD group (5.5 ± 1.9/cm²) was significantly lower than that in the control group (27.6 ± 14.4/cm²). The rate of perivascular plexuses on the surface of intramural vessels was also significantly lower in the CBD group than in the controls (37.7 ± 18.1 vs. 80.2 ± 17.4%, respectively). The numbers of ganglion cells per visual field were 38.5 ± 24.0 and 42.3 ± 20.6, respectively, in the CBD and control groups; this difference was not statistically significant.

Conclusions

There may be a mechanism in CBD causing contractile failure and dilatation of the biliary tract as a result of decreased intramural blood flow that accompanies the diminished vascularity.