UW pigment gallstones

Question 1

what bilirubin is increased in pigment stone formation?

Answer 1

unconjugated bilirubin

Question 2

due to incr. unconjugated bilirubin what substance is precipitated?

Answer 2

calcium-bilirubinate precipitation

Question 3

beta-glucuronidase is released by?2

Answer 3

injured hepatocytes and bacteria.

Question 4

what stones under infection?

Answer 4

brown

Question 5

what stones under hemolysis?

Answer 5

black

Question 6

what does beta-glucuronidase?

Answer 6

hydrolyzes bilirubin glucuronides and increases the amount of unconjugated bilirubin

Question 7

ileal disease, what stones?

Answer 7

black

Question 8

incr. enterohepatic cycling of bilirubin (ileal disease)?

Answer 8

black

Question 9

estrogens effect on HMG Co-A reductase?

Answer 9

estrogens upregulate HMG Co-A reductase, which increases cholesterol synthesis

Question 10

Desmolase (cholesterol side-chain cleavage enzyme) catalyzes the conversion of cholesterol to pregnenolone, which is the first step in the synthesis of steroid hormones.

Answer 10

.

Question 11

What substance induce formation of black stones?

Answer 11

Black gallstones form due to the supersaturation of bilirubin,

Question 12

bilirubin precipitate with what to form black stones?

Answer 12

precipitates with calcium to form multiple small calcium bilirubinate stones.

Question 13

Bilirubin supersaturation occurs through what mechanism?

Answer 13

Increased bilirubin production

Altered enterohepatic circulation of bilirubin

Question 14

why occurs increased bilirubin production?

Answer 14

chronic hemolysis

Question 15

what conditions leads to chronic hemolysis?

Answer 15

sickle cell anemia, hereditary spherocytosis, and thalassemia

Question 16

what bilirubin is increased due to chronic hemolysis disorders?

Answer 16

free bilirubin

Question 17

whats happens with free bilirubin due to chronic hemolysis?

Answer 17

increased circulating levels of free bilirubin, which is taken up by the liver and excreted into bile

Question 18

Altered enterohepatic circulation of bilirubin occurs in what condition?

Answer 18

Ileal disease (eg, Crohn disease) or resection allows bile acids, which are normally reabsorbed in the ileum, to spill into the colon. There, bile acids solubilize unconjugated bilirubin, allowing its reabsorption and concentration within the bile

Question 19

Stasis can occur due to gallbladder denervation. Eg what condiiton?

Answer 19

transection of the nerves that control gallbladder contraction

Question 20

Cirrhosis can also occasionally promote the formation of what stones?

Answer 20

black

Question 21

cirrhosis –> black. Why?

Answer 21

impaired bile acid synthesis and hyperbilirubinemia (due to cholestasis).