jaundice Flashcards
(34 cards)
what is physiological jaundice
Jaundice that begin day 2-3 and lasts for 10 day
What causes physiological jaundice
- more red blood cells with a shorter life span
- immature level unable to break down bilirubin
- immature gut means no bacteria to break down to urobillin meaning increased enterohepatic circulation
What is considered pathological jaundice
- <24hrs old
- rapid rise of bili >100
- sick newborn with jaundice
- serum bili >250 at 48hrs or >300 by 72hrs
- Failure to respond to phototherapy
- prolonged jaundice >14d in term and >21 in preterm
- cnjugated bili >35
- Pale, chalky stools and dark urine
What causes increase of bilirubin in the body
- ABO incompatibility
- inherited red cell membrane defects e.g. spherocytosis
- Erythrocyte enzymatic defects (G6PD] deficiency pyruvate kinase deficiency)
- sepsis
- polycythemia - macrosomia in diabetic mums
What causes a decreased clearance of bilirubin
Inherited defects in the gene that encodes UGT1A1
eg. Gilberts syndrome, Crigler-Najjar syndrome
What is Crigler Najjar syndrome
- disorder of bilirubin conjugation
- causes severe unconjugated hyperbilirubinemia
- can result in bilirubin-induced neurologic dysfunction
What inheritence pattern does Crigler Najjar syndrome have
rare, autosomal recessive
What causes Crigler-Najjar syndrome
absent or defective uridine diphosphate glucuronosyltransferase-1A1 (UGT1A1) enzyme
When do you suspect Crigler-Najjar syndrome
persistent unconjugated hyperbilirubinaemia
no underlying liver disease
no evidence of haemolysis
management of T1 Crigler Najjar syndrome
- avoid dehydration
- avoid medications that displace bilirubin
- chronic phototherapy
- liver transplant is curative.
what causes an acute exacerbation of crigler Najjar
- fasting
- infection
- hemolysis
- cholelithiasis
- cholecystitis
- general anesthesia.
What happens with an acute exacerbation of Crigler Najjar
- increase bilirubin production (hemolysis)
- reduce bile flow and bilirubin elimination (fasting, cholelithiasis, cholecystitis)
- and/or reduce plasma albumin
Management of acute exacerbation of Crigler Najjar
- intensive phototherapy
- albumin infusions
- plasmapheresis
management of T2 Crigler Najjar
phenobarbital
What is Gilberts syndrome
most common inherited disorder of bilirubin glucuronidation due to mutations in the UGT1A1 gene
What inheritence pattern is Gilberts syndrome
autosomal recessive
How do you diagnose Gilberts syndrome
hyperbillirubinaemia in the absence of haemolysis
What is breast milk jaundice
persistent benign hyperbilirubuniaemia beyond 2-3 weeks.
usually peaks within 2 weeks then resolves over 3-12 weeks
what is lactation failure jaundice
- inadequate intake of oral fluids and calorie intake resulting in weight loss + hypovolaemia
- Usually occurs in first week of life
- leads to hyperbilirubinaemia and sometimes hypernatraemia
What is kinicterus
- type of brain damage that can result from high levels of bilirubin
- can cause cerebral palsy and hearing loss.
what clinical signs would suggest a conjugated bilrubinaemia
dark urine
pale stools
What is biliary atresia
- extrahepatic bile ducts are obliterated by inflammation and subsequent fibrosis
- leading to biliary obstruction and jaundice.
- fatal if untreated
- unknown cause
what are the signs of biliary atresia
persistent jaundice (starts shortly after birth)
Pale stool
Dark urine
Failure to thrive
What investigation findings will you find in biliary atresia
- conjugated hyperbilirubinaemia
- GGT will be raised
