How do I know if I have Crigler-Najjar syndrome?

Crigler-Najjar syndrome is a rare genetic disorder characterized by the body’s inability to properly break down bilirubin, leading to persistent, high levels of unconjugated jaundice starting at or shortly after birth. Diagnosis is confirmed through specialized blood tests, genetic sequencing of the UGT1A1 gene, and clinical assessment by a hepatologist or metabolic specialist.

What are the early signs of Crigler-Najjar syndrome?

The primary hallmark of Crigler-Najjar syndrome is jaundice—a yellowing of the skin and the whites of the eyes (sclera)—that appears shortly after birth. Unlike common newborn jaundice, which typically resolves within a few weeks, the jaundice associated with Crigler-Najjar syndrome persists. Because this condition is rare, parents or adults investigating their health history should look for a pattern of life-long or chronic jaundice that does not respond to standard treatments. In Type I Crigler-Najjar syndrome, bilirubin levels are extremely high, which carries a risk of kernicterus (a form of brain damage caused by bilirubin accumulation), whereas Type II is generally milder.

How is Crigler-Najjar syndrome diagnosed?

If you suspect you or a family member may have Crigler-Najjar syndrome, it is important to consult a hepatologist or a metabolic disease specialist. Diagnosis involves a systematic approach to differentiate this condition from other liver disorders:

• Serum Bilirubin Testing: Measuring total and unconjugated (indirect) bilirubin levels.


• Liver Function Tests: Assessing liver enzymes (ALT, AST) to ensure the jaundice is due to bilirubin metabolism issues rather than liver cell damage or bile duct obstruction.


• Genetic Testing: Sequencing the UGT1A1 gene to identify specific mutations associated with Crigler-Najjar syndrome.


• Phenobarbital Response Test: A clinical trial of phenobarbital, which may help lower bilirubin levels in patients with Type II but is ineffective for Type I.

When should I seek urgent medical attention?

While Crigler-Najjar syndrome is a chronic condition, certain symptoms require immediate medical evaluation. If an individual with known or suspected Crigler-Najjar syndrome experiences sudden neurological changes—such as lethargy, poor feeding, extreme irritability, high-pitched crying, or muscle stiffness—this could indicate bilirubin toxicity. These "red flags" require an emergency room visit, as high bilirubin levels must be managed promptly to prevent neurological complications.

How can I advocate for myself if my concerns are dismissed?

Because Crigler-Najjar syndrome affects fewer than 1 in 1,000,000 people, many primary care physicians may never encounter a patient with this condition. If you feel your concerns are not being heard, prepare a concise summary of your symptoms, including a timeline of when the jaundice occurs and any family history of liver issues. Request a referral to a specialist at a major academic medical center or a metabolic liver disease clinic. You may also find comfort and shared knowledge by connecting with the 35 members of our DiseaseMaps.org community who are living with Crigler-Najjar syndrome.

Next steps

• Schedule an appointment with a hepatologist or a pediatric metabolic specialist.


• Request a copy of your medical records, specifically any historical liver function or bilirubin test results.


• Ask your doctor about the availability of genetic counseling to discuss the inheritance patterns of Crigler-Najjar syndrome.


• Join a dedicated support community, such as the Crigler-Najjar syndrome group on DiseaseMaps.org, to connect with others who have navigated the diagnostic process.

Medical disclaimer: This information is for educational purposes only and does not constitute medical advice; always consult with a qualified healthcare professional regarding your specific health concerns.

References

• NIH Genetic and Rare Diseases Information Center (GARD): Crigler-Najjar syndrome overview.


• Orphanet: Rare disease portal for Crigler-Najjar syndrome (ORPHA:205).


• OMIM (Online Mendelian Inheritance in Man): Entry #218800 (Type I) and #606785 (Type II).


• The Crigler-Najjar Syndrome Foundation: Clinical resources and patient support.