Criggler Najjar Syndrome
CRIGGLER NAJJAR SYNDROME
- Crigler–Najjar syndrome is a rare inherited disorder affecting the metabolism of bilirubin due to Genetic deficiency ot total absence of UDPG(uridine diphosphate glucuronyl) transferase.
- The disorder results in a form of nonhemolytic jaundice, which results in high levels of unconjugated bilirubin.
- Conversion of bilirubin to a water-soluble form is essential for its elimination is achieved by glucuronic acid conjugation with bilirubin.
- Bilirubin diglucuronide is a conjugated form of bilirubin formed in bilirubin metabolism
- Bilirubin is primarily excreted in normal human bile as diglucuronide
- The disorder is inherited in an autosomal recessive manner.
- This syndrome is divided into types I and II.
TYPE I OF CRIGGLER NAJJAR SYNDROME
- This is a very rare disease and consanguinity increases the risk of this condition.
- Intense jaundice appears in the first days of life and persists thereafter.
- Type 1 is characterised by a serum bilirubin usually above 345 µmol/L [20 mg/dL] .
- Bile is pale in type I .
- Conjugated bilirubin as Diglucuronide is absent in bile.
- No UDP glucuronosyltransferase 1-A1 expression can be detected in the liver tissue
- There is no response to treatment with phenobarbital.
- Kernicterus may develop.
TYPE II OF CRIGGLER NAJJAR SYNDROME
- Bilirubin levels are generally below 345 µmol/L [20 mg/dL].
- Some cases are only detected later in life.
- Bile is pigmented.
- There is a deficiency of Diglucuronide in the bile .
- UGT1A1 is present at reduced but detectable levels.
- Treatment with phenobarbital is effective.
- Kernicterus is rare in type II.
- Deficiency of Diglucuronide is present in Criggler-Najjar syndrome Type-II.
Don’t Forget to Solve all the previous Year Question asked on Criggler Najjar Syndrome