Gallbladder & extrahepatic bile ducts
Gallbladder nonneoplastic
Gallstone classification

Topic Completed: 1 September 2012

Minor changes: 5 September 2019

Copyright: 2003-2019,, Inc.

PubMed Search: Gallstone[TI] classification

Hanni Gulwani, M.B.B.S.
Page views in 2019: 1,753
Page views in 2020 to date: 1,174
Cite this page: Gulwani H. Gallstone classification. website. Accessed August 13th, 2020.
Definition / general
  • Gallstones are composed of insoluble bile components: cholesterol, calcium bilirubinate, calcium salts (organic and inorganic), bile salts, mucin glycoproteins
  • In U.S., 75 - 85% are cholesterol stones, 15 - 25% are pigment stones
  • Larger stones are associated with carcinoma (Trop Gastroenterol 2012;33:39); also cholesterol, not pigment stones (Aust N Z J Surg 2000;70:667)
  • Calcium stones are gray white and amorphous; very uncommon
  • Calcium carbonate may fill lumen as thick, inspissated, cream gray to yellow green putty-like material
Cholesterol stones
Definition / general
  • 75 - 85% of all gallstones
  • Only 10% are pure (at least 90% cholesterol), the remainder are mixtures with at least 60% cholesterol by weight
  • Cholesterol monohydrate precipitates when no longer soluble in bile
  • Initially bile supersaturation with cholesterol occurs
  • Then nucleation (initial crystallization), then stone growth facilitated by bile stasis and mucin hypersecretion
  • Pure and mixed occur predominantly in women
  • Also associated with increasing age, obesity, rapid weight loss, diabetes, ileal disease, multiple pregnancies, total parenteral nutrition, various drugs, specific ethnic groups
  • Adenomatous hyperplasia and Rokitansky-Aschoff sinuses:associated with mixed and cholesterol stones; not associated with pigment stones (Trop Gastroenterol 2002;23:25)

Gross description
  • Less than 1 cm to 4 cm
  • Single or multiple
  • White yellow, round / oval with crystalline cut surface
Pigment stones
Definition / general
  • 15 - 25% of all gallstones
  • Associated with increasing age
  • Less than 25 - 35% cholesterol
  • Composed of calcium bilirubinate, calcium salts, mucin glycoprotein
  • Brown (not black) stones associated with infected bile (usually E. coli) due to acute cholecystitis or choledocholithiasis with cholangitis
  • Black stones associated with older age, chronic hemolysis, cirrhosis, sclerosing cholangitis (increased unconjugated bilirubin in bile)

Gross description
  • Multiple shiny black stones, 0.2 to 5 cm, rarely brown in U.S. (more commonly brown in Japan)

Gross images

Images hosted on other servers:

Two pigment gallstones

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