Jaundice

Jaundice

·        Key question is why, not by how much (although this is important too)

·        Two types of bilirubin:

o  Unconjugated: 

§  If ­­unconjugated ® kernicterus: cerebral palsy, deafness, ¯IQ

§  Can die acutely (seizures, bilirubin encephalopathy) 

§  If survive: deaf, athetoid cerebral palsy (snake like movements – the harder they try to move the harder it becomes), normally intelligent

o  Conjugated: water soluble, conjugated in liver by glucuronyl transferase

·        Early onset (in 1^st 24 hours):

o  Always pathological

o  Causes: 

§  Haemolysis of any cause (eg Rhesus, ABO blood incompatibility, spherocytosis, G6PD deficiency etc)

§  Sepsis: respiratory distress + jaundice (not common)

o  Exam:

§  Maybe hydrops fetalis, large liver, large spleen (site of haemopoesis in newborn) 

§  Sepsis: especially breathing (indrawing and difficulty) – if in doubt then culture and stat antibiotics

o  Prevention:

§  Expect ABO if they‟ve had it before

§  Check for Rhesus disease

·        Jaundice in 1^st week:

o  Emphasis on extent of the jaundice (as well as consideration of the cause)

o  Treatment:

§  Phototherapy (visible light at the blue end of the spectrum – not UV)

§  Exchange transfusion

·        Persistent jaundice:

o  If it doesn‟t got away by 10 – 14 days then revisit

o  Causes: 

§  ­Conjugated bilirubin (go green) – needs treatment

·        Liver obstruction abnormalities (eg biliary atresia, secondary to liver damage from infection, toxins, etc)

·        Hepatitis/liver inflammation 

§  Unconjugated (yellow) – needs treatment if high. Eg Breast milk jaundice – progesterone in breast milk delays maturation

o   Diseases picked up on Guthrie card causing jaundice:

§  Hypothyroidism

§  Galactosaemia

§  Cystic Fibrosis

·        Aside: ABO Blood Incompatibility 

o   Maternal antibodies from mother with type O blood attack fetal blood cells if type A, B, or AB. Not isoimmunisation – it‟s an existing immune response. Doesn‟t get worse with subsequent pregnancies 

o   Transfusion:

§  Want to transfuse type O RBCs – aren‟t antigenic to anyone

§  Want to transfuse type AB plasma – won‟t contain antibodies to either type A or B blood