Courvoisier's law states that in the presence of a palpably enlarged gallbladder which is non-tender 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 was made. These points are commonly misquoted or confused in the medical literature.
Exceptions
Exceptions to Courvoisier's law imply 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.. To reiterate, the law simply says that jaundice and non-tender, palpable gall bladders are caused by other things than chronic bile gallstone formation. The law does not say that these symptoms automatically mean pancreatic cancer. It just happens that pancreatic cancer is the most common cause that falls under Courvoisier's law. Other cause includes malignancy of the CBD, head of pancreas and ampulla of Vater.
Related conditions
A palpable tender gallbladder may be seen in acute acalculous cholecystitis, which commonly follows trauma or ischemia and causes acute inflammation of the gallbladder in the absence of gallstones. A palpable gallbladder without mild jaundice can also be seen in Mirizzi's syndrome. The following case is an illustration of using the rationale underlying the Courvoisier Law clinically. In a patient with a history of lung cancerpresenting with jaundice and a non-palpable gallbladder it is likely that it is caused by a double cancer affected the common hepatic ducts and not from metastasis to the lymph node causing obstructive jaundice. This is because in the latter case, location of the lymph node has got to be in the CBD and one would expect a palpable gallbladder. All these speculations assume that the patient did not have gallstone disease previously and that the patient does not have a history of other liver diseases.
