CALCIUM CARRBONATE GALL-STONES AND THEIR EXPERIMENTAL PRODUCTION

Abstract

The cystic duct or ampulla was obstructed by stone in 11 of 48 consecutive gallstone operations, of which 5 presented the picture of ordinary gallbladder hydrops, while the other 6 presented, in a partially collapsed gallbladder, separate deposits of Ca carbonate varying in density from a mucous suspension to a dense, coarse sand. A solid, coarse sand-like deposit of practically pure Ca carbonate was produced experimentally in the dog by ligation of the cystic duct, injection of streptococci and implantation of a human stone in the gallbladder. Small Ca deposits were obtained by similar procedures in rabbits. From the human cases and the animal experiments, it appears that obstruction to the outlet of the gallbladder and a low-grade chronic inflammation, are essential for the formation of separate deposits of Ca carbonate in the gall-bladder. The limited chemical analysis of gallbladder fluids indicates that the Ca carbonate is precipitated from a solution in which Ca and carbonate ions accumulate in amts. which exceed the solubility product constant. The Ca is derived from the wall of the gall-bladder. The absence of cholesterol in the fluid beyond the amts. contained in exudates speaks against the wall of the gallbladder being the source of cholesterol in gall stones. Study of the cases in which cholesterol or cholesterol-pigment gall stones contained secondary ring deposits of Ca carbonate, with the cystic duct either obstructed or unobstructed, showed that the Ca carbonate is laid down in gallbladders with disturbed or lost concentrating function as a result either of inflammation or of inflammation plus calculous obstruction, complete or incomplete. The conditions indicate that the ring deposits of Ca carbonate come from the wall of the gall-bladder.