Jaundice

Background

• Bilirubin is end product of heme metabolism
  • All bilirubin products in the body are initially unconjugated
  • Transported from albumin into hepatocytes; combine with glucuronic acid into conj bili
    • Excreted into biliary tract in conjugated form
• Only conjugated bilirubin is water-soluble (present in urine)
• Nl bilirubin level is <1.1, 70% unconjugated

Jaundice Types

• • Prehepatic (overproduction)
    • Hemolysis
    • Primarily unconj bili
  • Hepatic (inadequate processing)
    • Viral, alcohol, toxin
    • Primarily unconj bili
  • Posthepatic (underexcretion)
    • Pancreatic tumor, choledocholithiasis
    • Primarily conj bili

Liver Function Tests

1. Transaminases
   1. Transaminitis in hundreds a/w mild injury; thousands suggests extensive injury
   2. Elevations <5x normal typical of alcoholic liver disease
   3. AST:ALT ratio > 2 common in alcoholic hepatitis (alcohol stimulates AST production)
   4. May be normal in end-stage liver failure
   5. ALT more specific marker of hepatocyte injury than AST
2. Alk phos
   1. Mild to moderate elevations accompany virtually all hepatobiliary disease
   2. Elevations > 4x normal suggest cholestasis
3. GGT
   1. Elevation in setting of hepatitis suggestive of alcoholic etiology
4. LDH
   1. Moderate elevations are seen in all hepatocellular disorders and cirrhosis
   2. Hemolysis results in elevation of LDH and unconj bili
5. Ammonia
   1. Elevation doesn't correlate w/ acute worsening of hepatic function in cirrhotic pt
   2. Serve as marker of generalized decline than as diagnostic tool or therapeutic end point
6. Coags
   1. Marker of synthetic function
   2. Correlation between PT prolongation and clinical outcome in fulminant liver disease
7. Albumin
   1. Marker of synthetic function
      1. Half-life is 3wk so less useful than PT in evaluating fulminant liver disease
   2. Low levels also seen in malnutrition

Workup

1. Urine pregnancy
2. CBC
3. Chemistry
4. LFT
   1. Hepatocyte injury: AST, ALT, alk phos
   2. Hepatocyte catabolic activity: Bilirubin
5. Coags
   1. Hepatocyte synthetic function
6. Albumin
   1. Hepatocyte synthetic function
7. Ammonia
   1. Hepatocyte catabolic activity
8. Acute hepatitis panel
9. Lipase
10. UA
11. ?US vs. CT
12. ?Retic count
13. ?Haptoglobin/LDH
14. ?APAP/ASA/Utox/ETOH

Diagnosis

Masqueraders:

1. Carotenemia
2. Quinacrine ingestion
3. Dinitrophenol, teryl (explosive chemicals)

NB: Only bilirubin stains the sclera

DDX

1. Indirect >> direct (Hematologic) [near nl AST/ALT/Alk P/PT/PTT]
   1. Hemolytic
      1. G6PD
      2. Drug related
      3. Autoimmune
   2. Hematoma resorption
   3. Infective erythropoiesis
   4. Gilbert's
2. Direct >> indirect
   1. Increased Alk P (Obstructive) [nl to mild inc AST/ALT]
   2. Choledocholithiasis
   3. Cholecystitis
   4. Cholangitis (Ascending)
   5. AIDS cholangiopathy
   6. Stricture
   7. Neoplasm
      1. Panc head
      2. Gallbladder
      3. Primary liver
      4. Metastatic
   8. Obstructing AAA
3. Nl Alk P (Hepatocellular/cholestatic) [greatly elevated AST/ALT]
   1. Viral hepatitis
   2. Fulminant hepatic failure
   3. ETOH hepatitis
   4. Ischemia
   5. Toxins
      1. isoniazide
      2. phenytoin
      3. acetaminophen
      4. ritonavir
      5. halothane
      6. sulronamide
   6. Autoimmune hepatitis
      1. 1 biliary cirhosis
   7. HELLP syndrome
   8. Congestive
      1. CHF
      2. Sepsis

Pregnancy Related

1. HELP
2. Acute fatty liver
3. Hyperemesis gravidarum
4. Cholestasis of pregnancy

Transplant Related

1. Transplant regection
2. Graft-vs-host

Peds Related

1. Inborn error of metabolism
2. Physiologic neonatal

Additional DDX

1. Reye's syndrome
2. TPN
3. Heatstroke
4. Budd-Chiari (with acute ascites)
5. Wilson's
6. Sarcoidosis
7. Amyloidosis

Disposition

New Onset Jaundice Admission Criteria

1. Transaminase >1000IU/L
2. Tbil >10mg/dL
3. Evidence coagulopathy

See Also

• Neonatal Jaundice
• Hepatitis

Source

• Tintinalli
• Rosen's