Bile acids algorithm

Use results to:

Assess liver function
Identify occult liver disease
Evaluate for vascular anomalies
Monitor patients on hepatotoxic medication

Clinical signs and diagnostic findings consistent with hepatobiliary disease

Clinical signs
Breed predilection
Poor growth in young animal
Poor recovery from anesthesia/sedation
Neurologic signs
History of hepatotoxic medication
Weight loss
Anorexia/vomiting/diarrhea
Ascites
Icterus*

CBC
Decreased and/or low normal MCV

Urinalysis
Ammonium biurate crystals
Bilirubin (feline)

Chemistry panel
Decreased or low normal:

BUN
Albumin
Glucose
Cholesterol

Increased:

ALT, AST, GGT, ALKP (persistent elevation or ≥ 3x upper end of reference interval)
Total bilirubin*

*If patient is icteric or if bilirubin is increased, rule out prehepatic causes and proceed without bile acids testing (see below).

2 or more of the above clinical indicators?

Consider extrahepatic diseases where appropriate; perform pre- and postprandial bile acids*

Normal

Canine
Preprandial: 0–14.9 μmol/L
Postprandial: 0–29.9 μmol/L

Feline
Preprandial: 0–6.9 μmol/L
Postprandial: 0–14.9 μmol/L

Does not rule out the presence of hepatobiliary disease

Mild elevation

Canine
Pre- or postprandial: 30.0–40.0 μmol/L

Feline
Pre- or postprandial: 15.0–30.0 μmol/L

Can be seen with both extrahepatic and hepatobiliary disease

Moderate to severe elevation

Canine
Pre- or postprandial: >40.0 μmol/L

Feline
Pre- or postprandial: >30.0 μmol/L

Consistent with hepatic dysfunction and/or cholestatic liver disease

Rule out extrahepatic causes

Consider supportive care and reevaluate as appropriate

Continued suspicion of primary hepatobiliary disease?

Investigate for underlying hepatobiliary disease

Increased bile acids and/or hepatic enzymes?

Evaluate for extrahepatic diseases

Possible causes

Pancreatitis
Gastrointestinal disease
Endocrine
- Hyperadrenocorticism
- Hyperthyroidism
- Diabetes mellitus
Extrahepatic neoplasia
Hypoperfusion (congestive heart failure, shock)
Trauma
Drug induced (ALKP/GGT)
- Steroids, phenobarbital
Muscular disease (ALT/AST)
Osteolytic disease/bone (ALKP)

Consider performing

Spec cPL Test/Spec fPL Test
Diagnostic imaging
Endocrine testing

Investigate underlying hepatobiliary disease