Symptoms of Hyperbilirubinemia
The primary symptoms of hyperbilirubinemia include jaundice (yellowing of the skin and eyes), which progresses from the face downward to the trunk and extremities, and in severe cases can lead to acute bilirubin encephalopathy and kernicterus with potentially devastating neurological consequences. 1
Visual Manifestations
- Jaundice: Yellow discoloration typically appears first in the face and progresses caudally to the trunk and extremities 1
- Visible yellowing of the skin occurs when serum bilirubin levels exceed 2.5-3 mg/dL 2
- Visual assessment alone is unreliable for determining bilirubin levels and can lead to errors 1
Neurological Symptoms of Acute Bilirubin Encephalopathy
Acute bilirubin encephalopathy progresses through three phases with increasing severity:
Early Phase
- Lethargy
- Hypotonia
- Poor feeding/sucking 1
Intermediate Phase
- Moderate stupor
- Irritability
- Hypertonia
- Fever
- High-pitched cry
- Alternating drowsiness and hypotonia
- Retrocollis (backward arching of neck)
- Opisthotonos (arching of the trunk) 1
Advanced Phase (likely irreversible)
- Pronounced retrocollis-opisthotonos
- Shrill cry
- No feeding
- Apnea
- Fever
- Deep stupor to coma
- Seizures
- Death 1
Chronic Bilirubin Encephalopathy (Kernicterus)
Long-term consequences in surviving infants may include:
- Severe form of athetoid cerebral palsy
- Auditory dysfunction
- Dental-enamel dysplasia
- Paralysis of upward gaze
- Intellectual and other handicaps 1
Special Considerations
- Not all infants with high bilirubin levels exhibit clinical signs of acute bilirubin encephalopathy before developing kernicterus 1
- Sick and immature infants are most vulnerable to bilirubin toxicity 3
- Risk factors that can exacerbate hyperbilirubinemia include:
- Acidosis
- Sepsis
- Hypoxia
- Hemolysis
- Hypoalbuminemia
- Certain medications that compete for albumin binding 3
Monitoring and Assessment
- Transcutaneous bilirubin (TcB) measurement devices can provide estimates within 2-3 mg/dL of total serum bilirubin (TSB) levels 1
- TcB measurements become unreliable in infants undergoing phototherapy due to skin "bleaching" 1
- In breastfed infants, inadequate intake (which can worsen jaundice) may be indicated by:
- Weight loss >10% of birth weight
- Fewer than 4-6 thoroughly wet diapers in 24 hours
- Fewer than 3-4 stools per day by the fourth day 1
Implications for Different Age Groups
While the guidelines primarily focus on neonatal hyperbilirubinemia, it's important to recognize that hyperbilirubinemia in adults typically indicates underlying liver disease, biliary obstruction, or disorders of bilirubin metabolism 2, 4. The symptoms may be similar (jaundice) but the causes and management differ significantly.
Hyperbilirubinemia is a serious condition that requires prompt evaluation and management, particularly in newborns, as it can lead to permanent neurological damage if severe cases progress to kernicterus 5.