Neonatal hepatitis

Neonatal hepatitis is a clinical syndrome of hepatic inflammation and conjugated (direct) hyperbilirubinemia in the newborn, representing over 100 possible underlying etiologies ranging from benign self-limited conditions to life-threatening emergencies. The critical task for the emergency physician is to recognize conjugated hyperbilirubinemia as always pathologic, distinguish it from benign physiologic jaundice, initiate a systematic workup, and urgently identify time-sensitive diagnoses — especially biliary atresia (which requires surgery before 60 days of life) and fulminant causes (sepsis, HSV, galactosemia, tyrosinemia).

Background

• Neonatal cholestasis occurs in approximately 1 in 2,500 live births
• Conjugated (direct) hyperbilirubinemia is NEVER physiologic and NEVER normal — it always requires evaluation
• Definition of conjugated hyperbilirubinemia:
  • Direct bilirubin > 1 mg/dL (regardless of total bilirubin), OR
  • Direct bilirubin > 20% of total bilirubin (if total > 5 mg/dL)
• The term "neonatal hepatitis" historically referred to "idiopathic neonatal hepatitis" (a diagnosis of exclusion after all identifiable causes are ruled out) — this accounts for ~26% of cases
• Most common identifiable causes:
  • Biliary atresia (~26%) — the most time-sensitive surgical diagnosis
  • Infections (~11%) — CMV is the most common infectious cause
  • TPN-associated cholestasis (~6%)
  • Alpha-1 antitrypsin deficiency (~4%)
  • Metabolic diseases (~4%) — galactosemia, tyrosinemia type 1, cystinosis
  • Perinatal hypoxia/ischemia (~4%)

EM critical rule

• Any infant jaundiced beyond 2 weeks of age (3 weeks if breastfed and otherwise well) must have a fractionated bilirubin — this single step prevents the most consequential missed diagnosis

Clinical features

Cardinal triad of neonatal cholestasis

• Jaundice (persisting beyond 2 weeks)
• Acholic (pale/clay-colored) stools — absent bile pigment indicates biliary obstruction
• Dark urine (conjugated bilirubin excreted renally)

Features suggesting specific etiologies

Biliary atresia (most time-sensitive)

• Term infant, often appears well initially
• Progressive jaundice with acholic stools (single most important clue)
• Hepatomegaly (firm liver)
• May have associated situs inversus or polysplenia (biliary atresia splenic malformation syndrome)
• No hepatic synthetic failure early (unlike metabolic/infectious causes)
• Kasai hepatoportoenterostomy must be performed before 60 days of age for best outcomes; delays worsen prognosis dramatically

Infectious causes (may present as sepsis)

• Neonatal herpes simplex (HSV) — fulminant liver failure, DIC, vesicular rash (may be absent), seizures; acyclovir must be started empirically if suspected
• TORCH — toxoplasmosis, rubella, CMV, HSV, syphilis; may present with hepatosplenomegaly, petechiae, microcephaly, chorioretinitis, intracranial calcifications
• Bacterial sepsis — UTI (especially E. coli) is a common cause of cholestasis in young infants; gram-negative sepsis
• Enterovirus, adenovirus, parvovirus B19

Metabolic emergencies

• Galactosemia — vomiting, poor feeding, hepatomegaly after introduction of lactose-containing formula/breast milk; E. coli sepsis association; cataracts; reducing substances in urine; STOP galactose-containing feeds immediately
• Tyrosinemia type 1 — liver failure with coagulopathy out of proportion to transaminases; very high AFP; "boiled cabbage" odor; Fanconi syndrome
• Hereditary fructose intolerance — hepatic failure after introduction of fructose/sucrose to diet
• Neonatal hemochromatosis (gestational alloimmune liver disease; GALD) — severe liver failure present at birth or within hours; high ferritin; requires exchange transfusion/IVIG
• Hypothyroidism — may present with prolonged jaundice; check TSH
• Cystic fibrosis — meconium ileus history; may present with cholestasis

Other causes

• Alpha-1 antitrypsin deficiency — most common genetic cause of liver disease in children; may present as neonatal cholestasis or later as cirrhosis
• Alagille syndrome — characteristic facies (broad forehead, pointed chin, deep-set eyes), butterfly vertebrae, cardiac murmur (peripheral pulmonic stenosis), posterior embryotoxon on eye exam
• Progressive familial intrahepatic cholestasis (PFIC) — various subtypes; severe pruritus (may not be apparent in neonates)
• TPN-associated cholestasis — in premature infants receiving prolonged parenteral nutrition
• Choledochal cyst — may present as a palpable RUQ mass with jaundice

General examination findings

• Hepatomegaly (nearly universal in cholestasis)
• Splenomegaly (suggests portal hypertension, storage disease, or infection)
• Growth failure, poor feeding
• Coagulopathy/bleeding (vitamin K deficiency from fat malabsorption, or hepatic synthetic failure)
• Stool color is critically important — ask caregivers and inspect stools directly

Differential diagnosis

Must-not-miss (time-sensitive or life-threatening)

• Biliary atresia — surgery before 60 days
• Neonatal HSV — acyclovir immediately
• Bacterial sepsis/UTI — antibiotics immediately
• Galactosemia — stop lactose immediately
• Tyrosinemia type 1 — start nitisinone
• Neonatal hemochromatosis (GALD) — exchange transfusion/IVIG

Common causes

• Idiopathic neonatal hepatitis (diagnosis of exclusion)
• TORCH infections (especially CMV)
• TPN-associated cholestasis (premature infants)
• Alpha-1 antitrypsin deficiency
• Alagille syndrome

Conditions that mimic cholestasis (unconjugated)

• Physiologic jaundice (unconjugated; resolves by 2 weeks)
• Breast milk jaundice (unconjugated; benign; may persist 3+ weeks)
• Hemolytic disease (ABO/Rh incompatibility)
• Gilbert syndrome, Crigler-Najjar syndrome
• These are distinguished by fractionated bilirubin — the direct fraction will be normal

Evaluation

ED workup

• Fractionated (total and direct) bilirubin — the single most important initial test; identifies conjugated hyperbilirubinemia
• Hepatic function panel: AST, ALT, GGT, alkaline phosphatase, albumin
  • GGT is particularly useful: markedly elevated in biliary atresia and bile duct disorders; normal/low in PFIC
• Coagulation studies (PT/INR): hepatic synthetic function; also assesses vitamin K deficiency
• CBC with differential: infection, anemia, thrombocytopenia
• Blood glucose: hypoglycemia (metabolic diseases, liver failure)
• BMP: electrolytes, renal function
• Blood cultures, urinalysis, urine culture — sepsis/UTI workup in any ill-appearing infant
• Newborn screening results — review if available; many metabolic causes are screened

Directed second-tier testing (initiate from ED or arrange urgently)

• Abdominal ultrasound: evaluate for biliary atresia (absent/atretic gallbladder, triangular cord sign), choledochal cyst, gallstones; does not reliably exclude biliary atresia
• TORCH titers/PCR: CMV urine PCR, HSV PCR, rubella, toxoplasmosis, syphilis (RPR/VDRL)
• Urine reducing substances: positive in galactosemia (but not specific; false negatives occur)
• TSH, free T4: hypothyroidism
• Alpha-1 antitrypsin level and phenotype
• Urine succinylacetone: pathognomonic for tyrosinemia type 1
• Serum ferritin, transferrin saturation: neonatal hemochromatosis (ferritin often massively elevated)
• AFP (alpha-fetoprotein): markedly elevated in tyrosinemia; elevated in normal neonates but should be declining
• Sweat chloride or immunoreactive trypsinogen: if cystic fibrosis suspected
• Galactose-1-phosphate uridylyltransferase (GALT) activity: confirms galactosemia

When to suspect biliary atresia

• Full-term infant with persistent acholic stools + conjugated hyperbilirubinemia + hepatomegaly
• GGT markedly elevated
• Absent or atretic gallbladder on ultrasound (though ultrasound sensitivity is imperfect)
• Refer urgently to pediatric surgery/hepatology — do not wait for complete workup if clinical suspicion is high; intraoperative cholangiogram is the gold standard

Management

Immediate ED management

• Vitamin K: administer 1 mg IM (neonatal dose) to any infant with cholestasis and coagulopathy — fat-soluble vitamin malabsorption causes vitamin K deficiency and bleeding risk; this can be life-saving
• NPO if acutely ill until stabilized; IV dextrose-containing fluids to prevent hypoglycemia
• Empiric antibiotics if sepsis suspected (ampicillin + gentamicin or cefotaxime per neonatal protocol)
• Empiric acyclovir if any suspicion for neonatal HSV (do not wait for HSV PCR results; disseminated HSV with hepatitis carries >80% mortality without treatment)
• Stop galactose-containing feeds (breast milk and standard lactose-based formula) if galactosemia suspected — switch to soy-based formula
• Stop fructose/sucrose if hereditary fructose intolerance suspected
• Correct coagulopathy with vitamin K; FFP if active bleeding
• Correct hypoglycemia with IV dextrose

Supportive care

• Fat-soluble vitamin supplementation (A, D, E, K) — arrange through pediatric GI
• For formula-fed infants: MCT-enriched formula (medium-chain triglycerides are absorbed without bile salts)
• Ursodeoxycholic acid (UDCA) — choleretic agent; may be started by GI/hepatology for some causes of intrahepatic cholestasis

Disease-specific management (arrange via specialist)

• Biliary atresia: Kasai hepatoportoenterostomy (ideally before day 45-60 of life)
• Tyrosinemia type 1: nitisinone + low-tyrosine diet (see Tyrosinemia)
• Galactosemia: strict galactose-free diet
• Neonatal hemochromatosis (GALD): exchange transfusion + IVIG (consult neonatology/hepatology emergently)
• Alpha-1 antitrypsin deficiency: supportive; liver transplant if progressive
• Hypothyroidism: levothyroxine

Disposition

• All infants with confirmed conjugated hyperbilirubinemia should be admitted or have same-day/next-day urgent pediatric GI/hepatology follow-up arranged from the ED
• Admit to hospital (often NICU/PICU):
  • Any ill-appearing infant
  • Suspected sepsis, HSV, or metabolic emergency
  • Coagulopathy or active bleeding
  • Hepatic failure (elevated INR, hypoglycemia, encephalopathy)
  • Suspected biliary atresia — urgent surgical consultation
• Urgent outpatient referral (if well-appearing, stable, feeding well):
  • Conjugated hyperbilirubinemia confirmed but infant is clinically well
  • Pediatric GI/hepatology appointment within 24-48 hours
  • Ensure caregivers understand return precautions: fever, pale stools, increasing jaundice, bleeding, poor feeding, lethargy
• Communicate stool color education: provide caregivers with a stool color card if available (used in some countries for biliary atresia screening); instruct them to report acholic/pale stools immediately
• Do not attribute persistent jaundice beyond 2 weeks to "breast milk jaundice" without fractionating bilirubin — this is the most common cause of delayed diagnosis of biliary atresia and other serious conditions

See Also

• Neonatal jaundice
• Biliary atresia
• Neonatal HSV
• Galactosemia
• Tyrosinemia
• Fanconi syndrome
• Cystinosis
• Sepsis
• TORCH infections
• Neonatal hemochromatosis

External Links

• NASPGHAN/ESPGHAN — Guideline for the Evaluation of Cholestatic Jaundice in Infants (2017)
• Pediatr Rev — Neonatal Cholestasis (2014)
• BMC Pediatr — Etiologies of conjugated hyperbilirubinemia in infancy (2015)
• Front Pediatr — Neonatal Cholestasis: Differential Diagnoses, Current Diagnostic Procedures, and Treatment (2015)
• Merck Manual — Neonatal Cholestasis