Biliary tubage, is interesting in the aetiological research of acute pancreatitis, when the origin is unknown after anamnesis, clinical examination, abdominal ultrasonographic studies and retrograde cholangiography. The sludge is the aetiology fond in 40% of the cases. Microscopic crystals are either cholesterol monohydrate, either calcium bilirubinate, or calcium carbonate microspheroliths. Biliary microscopic crystals drive the patients to the cholecystectomy to prevent acute pancreatitis relapses.