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Peritoneum and peritoneal cavity disorders






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A 72-year-old woman comes to the emergency department because of intermittent crampy abdominal pain associated with nausea and vomiting for the last five days. She had an episode of vomiting with hematemesis six hours ago. Past medical history is significant for diabetes mellitus, gallstones, and hypertension. Current medications are metformin and lisinopril. Temperature is 38.2°C (100.8°F), pulse is 118/min, respirations are 22/min, and blood pressure is 110/60 mm Hg. Abdominal examination shows distention and tenderness, and hyperactive high-pitched bowel sounds are heard on auscultation. An abdominal radiograph shows pneumobilia and dilated loops of small bowel. Laboratory results are shown below:  
 Laboratory value Result 
Leukocyte count  23,250/mm3 
 Hemoglobin  12 g/dL 
 Hematocrit  46% 
 Platelets  400,000/µL 
 Lipase  140 U/L 
 AST, SGOT  47 U/L 
 ALT, SGPT  45 U/L 
 Total bilirubin  0.8 mg/dL 
Which of the following is the most likely underlying cause of this patient's presentation? 

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Alcoholic cirrhosis p. 69, 400

cholelithiasis and p. 405

Bile salts p. 383

in cholelithiasis p. 405

Biliary tract disease p. 404

gallstones p. 377

Bilirubin p. 384

cholelithiasis p. 405

Cholelithiasis p. 405

acute pancreatitis p. 405

bile ducts and p. 377

biliary cirrhosis and p. 405

Crohn disease p. 391

hyperbilirubinemia and p. 402

octreotide and p. 409

somatostatinomas p. 357


cholelithiasis and p. 405

Cirrhosis p. 398

cholelithiasis and p. 405

Crohn disease p. 391

cholelithiasis and p. 405

Gallstones p. 404

Ileus p. 395

gallstone p. 405


cholelithiasis and p. 405

Weight loss

cholelithiasis and p. 405


Content Reviewers

When you eat some real fatty foods, like say some delicious french fries, they make their way to through the stomach and into the small intestine. At this point they aren’t really french fries anymore, but since they’re high in fat, they’re still a little more difficult to absorb, and that’s where your gallbladder comes in.

This high fat food stimulates the gallbladder to squeeze out some bile into the small intestine, that bile emulsifies the fat, or basically mixes the fat up, and makes it easier to absorb.

This is pretty much your gallbladder’s job—store and concentrate bile until the time comes to send it to the small intestine. It’s not the most glamorous of jobs, but hey, gotta start somewhere.

If we take a closer look at this magical substance, we’d get a rough breakdown that’s something like the following: ~70% bile salts and acids, ~10% cholesterol ~5% phospholipids, ~5% proteins, and 1% conjugated bilirubin, and the rest, small amounts of various other compounds like water, electrolytes, and bicarbonate.

Bile salts and acids are mostly a product of cholesterol metabolism, so an acid might look something like this and its salt is the anionic form, something like this (ROO-) group.

These acids and their salts have both hydrophobic and hydrophilic sides, making them amphiphilic, which help them make cholesterol and fat in the gut more soluble in bile.

The phospholipids are mostly lecithin, also amphiphilic, and also help make cholesterol and fats more soluble in bile.

Gall-stones are these round and solid stones you can find inside your gallbladder, and they’re made from the components of bile, and so they’re categorized depending on what they’re made of, the most common ones are cholesterol stones, but there’s also bilirubin stones, which are sometimes called pigmented stones.

The first type, as you might guess, are made mostly of cholesterol that has precipitated out of the bile as a solid and formed these solid stones. These account for around 75 to 90% of cases.

This cholesterol precipitation can happen in a couple ways, first, the bile can become supersaturated with cholesterol, meaning that the bile has so much cholesterol that the bile salts and acids or phospholipids can’t hold any more in solution, because remember that these all help make the cholesterol more soluble in bile, and so the cholesterol comes out of solution as a solid.


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