A 43-year-old woman comes to the office with a 1-month history of dull abdominal pain that occurs mainly after eating. The pain is localized to the right upper quadrant and is especially severe after fatty meals. Physical examination is unremarkable. Ultrasound of the abdomen reveals several mobile echogenic foci within the gallbladder lumen. Which of the following sets of conditions is most likely present within this patient's gallbladder?

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11ec160b_3adb_fe1f_9249_1569d46dd2eb_MD0001_00 Removal of excess cholesterol from the body occurs via 2 mechanisms: excretion of free cholesterol into bile and conversion of cholesterol into bile acids. In the liver, free cholesterol is converted into cholic and chenodeoxycholic acids through a series of chemical reactions beginning with cholesterol 7α-hydroxylase (rate-limiting step in bile acid synthesis). These bile acids are then conjugated to either glycine or taurine (improving solubility and emulsifying ability) to create the bile salts that are actively secreted into the bile canaliculi. As water-insoluble cholesterol is secreted in bile, it is rendered soluble in small amounts by the detergent action of these amphipathic (eg, hydrophobic and hydrophilic) bile salts and phosphatidylcholine (a phospholipid). When there is more cholesterol than can be made soluble, it precipitates into crystals that eventually grow and merge to form gallstones. Gallbladder hypomotility further promotes cholesterol nucleation and gallstone formation. (Choices A, B, C, E, and F) These represent lower cholesterol concentrations related to total bile salt and phosphatidylcholine levels. Such conditions would decrease the likelihood of gallstone formation. Educational objective: Elevated cholesterol concentrations increase the likelihood of cholesterol precipitation and gallstone formation. High levels of bile salts and phosphatidylcholine increase cholesterol solubility and decrease the risk of gallstones. __________ References: Pathogenesis of gallstones (http://www.ncbi.nlm.nih.gov/pubmed/1529152) Pathogenesis of gallstones. (http://www.ncbi.nlm.nih.gov/pubmed/20478481)

A 43-Year-Old Woman Comes to the Office with a 1-Month