Courvoisier's law

Courvoisier's law (or Courvoisier syndrome, or Courvoisier's sign or Courvoisier-Terrier's sign) states that in the presence of a palpably enlarged gallbladder which is nontender and accompanied with mild painless jaundice, the cause is unlikely to be gallstones. Usually, the term is used to describe the physical examination finding of the right-upper quadrant of the abdomen. This sign implicates possible malignancy of the gallbladder or pancreas and the swelling is unlikely due to gallstones.

This observation occurs because gallstones are formed over an extended period of time, resulting in a shrunken, fibrotic gallbladder which does not distend easily and is less likely to be palpable on exam. In contrast, the gallbladder is more often enlarged and thus more easily palpated in pathologies that cause obstruction of the biliary tree over a more acute, shorter period of time such as pancreatic malignancy, leading to passive distention from back pressure.

Ludwig Georg Courvoisier's original observations, published in Germany in 1890, were not originally cited as a 'law', and no mention of malignancy or pain (tenderness) was made. These points are commonly missquoted or confused in the medical literature.

Exceptions to Courvoisier's law implies that a stone is responsible for jaundice and a non-tender, palpable gall bladder. Typically gall bladder stones form slowly which allow time for the gall bladder to become tender. The exceptions to the law are stones that dislodge and acutely block the duct distally to the hepatic/cystic duct junction:

Cholangiocarcinoma, Klatskin tumors, ascariasis, or recurrent pyogenic cholangitis are not exceptions to the law because they all fall under it. For example in the case of Recurrent pyogenic cholangitis complicated by calcium bilirubinate stone dislodging to the common bile duct causing a distended gallbladder by back pressure. (Where formation of stones are not strictly in gallbladder, hence not fibrotic, but in the intrahepatic bile ducts). To reiterate, the law simply says that jaundice and non-tender, palpable gall bladders are caused by other things than chronic bile gallstone formation.

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