DOES CHEMICAL-COMPOSITION HAVE AN INFLUENCE ON THE FATE OF INTRAPERITONEAL GALLSTONE IN RAT

Perforation and spillage of gallstones is a common occurrence in lapar oscopic cholecystectomies. The long-term complications of these stones remains controversial. Experimental studies have been carried out to elucidate the outcome of intraperitoneal gallstones, but the chemical composition of these stones has not been considered in previous studie s. In this study, we investigated the local effects of intraperitoneal gallstones in rats with respect to their chemical composition. Bile a nd gallstones were taken from human cholecystectomy specimens, and sen t for bacteriologic and chemical analysis. Twenty cholesterol and 10 p igment stones were placed in the abdominal cavity of rats. Long-term l ocal effects of gallstones were determined at the end of 3 months with macroscopic and microscopic examination. The fragments of two pigment stones were infected by Staphylococcus aureus. Five (17%) cholesterol stones were found free in the abdominal cavity, and 25 stones (83%) w ere wrapped with adjacent structures. Granuloma formation was found ar ound 4 pigment stones (13% of all stones, 40% of pigment stones; p = 0 .0077). We observed large granulomas and cutaneous fistula formation i n two rats with infected pigment stones placed in the abdominal cavity . Histhopathologic examination also showed significantly severe inflam matory reactions secondary to pigment stones (p < 0.001). In conclusio n our findings revealed that chemical composition has a significant in fluence on the fate of intraabdominal gallstones, and infection may ag gravate local reactions and complications. Based on our findings, lapa roscopic retrieval of spilled stones whenever possible seems to be use ful to prevent subsequent infectious complications and inflammatory re actions. Patients with retained intraperitoneal pigment stones after l aparoscopic cholecystectomy must be followed up closely.