Liver disease and jaundice Flashcards
What are the liver tests that show damage?
- Bilirubin
□ Total bilirubin
□ “Split” bilirubin – Direct (conjugated) + Indirect (unconjugated) - ALT/AST (alanine aminotransferase/aspartate aminotransferase)
□ Elevated in hepatocellular damage (“hepatitis) - Alkaline phosphatase
□ Elevated in biliary disease
□ Has to do with bone and so varies a lot in children thus not used that often - Gamma glutamyl transferase (GGT)
□ Elevated in biliary disease but also due to heart and muscles
What are the liver function tests?
- Coagulation
□ Prothrombin time (PT)/INR
□ APTT - Albumin: how well liver is producing proteins
- Bilirubin
- (Blood glucose)
□ Tends to go wrong when you have significant liver failure - (Ammonia)
□ Tends to go wrong when you have significant liver failure
What are the clinical manifestations of paediatric liver disease?
○ JAUNDICE
○ Incidental finding of abnormal blood test
What are the signs/symptoms of chronic liver disease in children?
- Growth failure
- Encephalopathy
- Jaundice
- Epistaxis
- Varices with portal hypertension
- Spider nevi
- Muscle wasting from malnutrition
- Bruising and petechiae
- Cholestasis
> Fat malabsorption
> Deficiency of fat-soluble vitamins
> Pruritis
> Pale stools
> Dark urine - Splenomegaly with portal hyerptension
- Hypersplenism
- Hepatorenal failure
- Ascities
- Liver palms
- Clubbing
- Loss of fat store secondary to malnutirion
- Hypotonia
- Rickets secondary to vitamin D deficiency
What is jaundice?
○ yellow discolouration of skin and tissues due to accumulation of bilirubin
○ Usually most obvious in sclera
○ Usually visible when total bilirubin >40-50 umol/l
What is the diagnosis of infant jaundice dependant on?
- Understanding bilirubin metabolism
- Age of infant
What are the causes of jaundice classified by age?
- Early (<24 hours old)
□ Always pathological
□ Causes: Haemolysis, Sepsis - Intermediate (24hrs – 2 weeks)
□ Causes: Physiological, Breast milk, Sepsis, Haemolysis - Prolonged (>2 weeks)
□ Causes: Extrahepatic obstruction, Neonatal hepatitis, Hypothyroidism, Breast milk
What is physiological jaundice?
□ Shorter RBC life span in infants (80-90 days) □ Relative polycythaemia □ Relative immaturity of liver function □ Unconjugated jaundice □ Develops after first day of life
What is breast milk jaundice?
□ Exact reason for prolongation of jaundice in breastfed infants unclear
® Inhibition of UDP by progesterone metabolite?
® Increased enterohepatic circulation?
□ Unconjugated jaundice
□ Can persist up to 12 weeks
Why do infants get jaundice with sepsis and what should be done to identify this?
□ Because they have an increase in haemolysis
□ Urine and blood cultures, TORCH screen
Why might an infant experiance haemolysis?
□ ABO incompatibility □ Rhesus disease □ Bruising/cephalhaematoma □ Red cell membrane defects (e.g. spherocytosis) □ Red cell enzyme defects (e.g. G6PD)
What are the causes of abnormal conjugation in infants?
□ Gilbert’s disease – common, mild (1 in 20)
□ Crigler-Najjar syndrome – v. rare, severe
What is a complication of early/ intermediate infant jaundice?
Kernicterus
What is Kernicterus?
□ Unconjugated bilirubin is fat-soluble (water insoluble) so can cross blood-brain barrier
□ Neurotoxic and deposits in brain
□ Early signs – encephalopathy – poor feeding, lethargy, seizures
□ Late consequences – severe choreoathetoid cerebral palsy, learning difficulties, sensorineural deafness
How is earlt/ intermediate infant jaundice treated?
- Phototherapy
□ Treatment for unconjugated jaundice
□ Visible light (450nm wavelength) (not UV) converts bilirubin to water soluble isomer (photoisomerisation)
□ Threshold for phototherapy in infants guided by charts
