Agenesis of the gallbladder: case report and familial investigation.

In this article we report a case of gallbladder agenesis, confirmed at laparotomy, and the subsequent investigation of that patient's family for others with evidence of agenesis. Ultrasonography was chosen as the principal diagnostic tool, and of the eight family members available for study, one was found to have no demonstrable gallbladder by either ultrasonography or oral cholecystography. The overall incidence of gallbladder agenesis is said to approximate 0.01% to 0.04%. However, in each of the four existing familial studies a much higher incidence is noted. With regard to gallbladder agenesis, these data strongly suggest the existence of a familial hereditary trait.