Hepatic hyperbilirubinemia

Question 1

Causes

Answer 1

Decrease Bu uptake
Decrease Bu conjugation
Decrease Bc excretion

Question 2

Decreased Bu uptake

Answer 2

Mostly horses effected
Fasting increases mobilization of fat stores and increases fatty acids in blood-> hepatocytes take in less unconjugated Bu from competition for Y and Z proteins-> decreased glucose for conjugation as well (horses)
No bilirubinuria because all the Bu is bound to albumin so not excreted in kidneys

Question 3

Increase in Bu from fasting

Answer 3

Can be as high as 10mg/dL but not higher

Question 4

Sick inappetent cattle Bu

Answer 4

Can be increased not associated with liver disease or hemolytic anemia

Question 5

Decreased functional hepatic mass

Answer 5

Marked reduction of functional hepatocytes result in decreased uptake and conjugation.

Question 6

Intrahepatic cholestasis

Answer 6

Impaired bile flow through canaliculi in liver
Usually due to hepatocellular swelling and collapse of canaliculi or altered architecture

Question 7

Consequence of intrahepatic cholestasis

Answer 7

Pressure forces bile our of canaliculi and small ductules and Bu enters sinusoidal blood and then into systemic circulation. There is regurgitation of Bu into blood after it is conjugated

Question 8

Functional cholestasis

Answer 8

Sepsis associated. Impaired excretion of Bc from hepatocytes to canaliculi in absence of physical obstruction from increased TNF alpha in infection. Will see bilirubinuria (very sick animals)

Question 9

Other findings of functional cholestasis

Answer 9

-Inflammatory leukogram
-Clinical evidence of infection
-Decreased bile acid and Bu secretion
-Increased serum Bu
-Minimal increase in ALP and GGT
-Increase in ALT
-Bilirubinuria