Jaundice

(Redirected from Hyperbilirubinemia)

For neonatal jaundice please see the Neonatal jaundice page

Background

Cycle of heme breakdown and excretion.
  • Bilirubin is end product of heme metabolism
  • All bilirubin products in the body are initially unconjugated and is transported bound to albumin into hepatocytes t o becombined with glucuronic acid into conjugated bilirubin
  • Conjugated bilirubin is then excreted into biliary tract
  • Only conjugated bilirubin is water-soluble (present in urine)
  • Normal bilirubin level is <1.1 (70% unconjugated)

Jaundice Types

Prehepatic (overproduction):

Hepatic (inadequate processing):

Posthepatic (underexcretion):

Clinical Features

Jaundice of the skin
Pediatric jaundice with icterus of sclera.
  • Yellow skin, sclera
  • +/- dark urine

Differential Diagnosis

Jaundice

Differential diagnosis of hyperbilirubinemia.

Indirect Hyperbilirubinemia

Direct (Conjugated) Hyperbilirubinemia

Hepatocellular damage

Patient will have severely elevated AST/ALT with often normal Alkaline Phosphatase

Pregnancy Related

Transplant Related

Pediatric Related

Additional Differential Diagnosis

Masqueraders

Only bilirubin stains the sclera

  • Carotenemia
  • Quinacrine ingestion
  • Dinitrophenol, teryl (explosive chemicals)

Evaluation

Evaluation algorithm
Lab test for jaundice
  • Urine pregnancy
  • CBC
  • Chemistry
  • LFTs
    • Hepatocyte injury: AST, ALT, alk phos
    • Hepatocyte catabolic activity: Bilirubin
  • Coags
    • Hepatocyte synthetic function
  • Albumin
    • Hepatocyte synthetic function
  • Ammonia
    • Hepatocyte catabolic activity
  • Acute hepatitis panel
  • Lipase
  • Urinalysis
  • ?US vs. CT vs MRCP
  • ?Retic count
  • ?Haptoglobin/LDH
  • ?APAP/ASA/Utox/ETOH

Liver function tests

Transaminases

  • Transaminases in hundreds associated with mild injury; thousands suggests extensive injury
  • Elevations <5x normal typical of alcoholic liver disease
  • AST:ALT ratio > 2 common in acute alcoholic hepatitis (alcohol stimulates AST production)
  • May be normal in end-stage liver failure
  • ALT more specific marker of hepatocyte injury than AST

Alk phos

  • Mild to moderate elevations accompany virtually all hepatobiliary disease
  • Elevations > 4x normal suggest cholestasis

GGT

  • Elevation in setting of hepatitis suggestive of alcoholic etiology

LDH

  • Moderate elevations are seen in all hepatocellular disorders and cirrhosis
  • Hemolysis results in elevation of LDH and unconjugated bili

Ammonia

  • Elevation does NOT correlate with acute worsening of hepatic function in cirrhotic patient
  • Serves as marker of generalized decline than as diagnostic tool or therapeutic end point

Coagulation Markers (PT/PTT/INR)

  • Marker of synthetic function
  • Correlation between PT prolongation and clinical outcome in fulminant liver disease

Albumin

  • Marker of synthetic function
    • Half-life is 3 weeks so less useful than PT in evaluating fulminant liver disease
  • Low levels also seen in malnutrition

Management

  • Management is dependent on the diagnosis of either conjugated or unconjugated hyperblirubinemia and the severity of the elevation

Disposition

New Onset Jaundice Admission Criteria

  • Transaminase >1,000 IU/L
  • Tbil >10mg/dL
  • Evidence coagulopathy

See Also

References