[An unusual complication of calculous cholecystitis: transparietal migration of a calculus into a circumscribed peritoneal sac without a fistulous passage].

A rare complication of calculous cholecystitis (calculous that had migrated from the gallbladder and held in a circumscribed peritoneal sac with no fistula between this and the gallbladder) was observed in a woman who had been suffering from dropsy of the gallbladder with calculi for some 13 years. The most recent literature on acute and chronic perforations of the gall bladder and on known pathogenetic mechanisms regarding transparietal migration of calculi and the establishment of bilio-digestive and bilio-biliar fistulas is reviewed. A number of hypotheses are put forward to explain the unusual operative finding but the impossibility of formulating any precise preoperative diagnosis is recognized and it is stressed that many cases are recognized only following surgery.