Page 721 - Clinical Small Animal Internal Medicine

63 Feline Inflammatory Liver Disease 689

RETICULOENDOTHELIAL CELL HEPATOCYTE
VetBooks.ir RED BLOOD CELL FERRITIN CHOLESTEROL
HEMOGLOBIN
CHOLICACID (1 )
GLOBIN
CO
BILIVERDIN Fe TRANSFERRIN
CHENODEOXYCHOLIC
BILIRUBIN ACID (1 )
BOUND TO ALBUMIN BILE CANALICULUS

BILIRUBIN + LIGANDIN PRIMARY BILE ACIDS

TAURINE Aminoacylamination GLYCINE
transferase
UDP glucuronyl
BILIRUBIN GLUCURONIDE CONJUGATED BILE ACIDS

• BILE DUCTULE
• INTRALOBULAR DUCT
ENTEROHEPATIC • INTERLOBULAR DUCT
RECIRCULATION • HEPATIC DUCT
• CYSTIC DUCT

GALL
BLADDER

COMMON BILE DUCT

RENAL
EXCRETION

DECONJUGATED CONJUGATED
BILE ACIDS BILE ACIDS
LITHOCHOLIC ACID (2 )
DEOXYCHOLIC ACUD (2 )
CONJUGATED
UROBILIN UROBILINOGEN BILIRUBIN
FECES STERCOBILIN
ILEUM
COLON DUODENUM
Figure 63.1 Diagrammatic representation of normal biliary physiology. Cholestasis results in hyperbilirubinemia and elevated bile acids.
With complete obstruction of the biliary system, urobilinogen will not be available for urinary excretion, and stercobilin will not be
present in the feces (acholic feces). Bacteria are responsible for deconjugation of bile acids and bilirubin, therefore these processes may
also be affected by abnormal gut flora.

inspissated, requiring use of a larger gauge needle and a definitive diagnosis. Due to the patchy distribution of
hence potentially increased risk of bile peritonitis. lesions, the larger samples obtained via laparoscopy or
Coagulation times may be prolonged due to vitamin K surgical wedge biopsies may be preferable to needle
deficiency, both as a result of anorexia but also because (“Tru‐cut”) biopsies. Ideally, both liver and bile should be
cholestasis reduces passage of bile acids into the intestine cultured, as different organisms may be cultured from
where they are required for absorption of this fat‐soluble each site, although culture of bile yields higher recovery
vitamin. Coagulation times should therefore always be of organisms than culture of liver. Anaerobic as well as
evaluated prior to liver biopsy. Liver biopsy is required for aerobic culture should be performed.