Neonatal jaundice



Background

Neonatal Jaundice is common in the first week of life (65 % of term infants are clinically jaundiced and 95 % have elevated serum bilirubin >17 mmol/l) but its clinical significance, investigation and treatment are contentious. It is important to respond to the presence of NNJ by thought and careful clinical examination rather than reflex action determined by graphs and lists of investigations. Important points to consider are the:

  • age at onset
  • rate of rise
  • peak concentration
  • profile (eg) secondary rise
  • duration of the jaundice

The vast majority of newborn infants do not have a pathological cause for their jaundice. However, jaundice may be a presenting sign of life threatening disease. Examine the baby in a well lit room. Blanch the skin.

Caution must be exercised when examining black and asian babies as it is sometimes very difficult clinically to assess the extent of the jaundice. Generally the bilirubin of a jaundiced baby should be checked once daily unless the baby is near exchange level or appears to have rapidly increasing jaundice.


Early jaundice

Do not assume early jaundice is physiological if

  • Jaundice visible in the first 24 hrs
  • Evidence of cholestasis – dark urine or pale stools
  • Evidence of haemolysis:
    • FHx of significant haemolysis
    • Pallor/ hepatosplenomegaly
    • Rapid increase in total bilirubin
  • Ethnicity suggestive of G6PD deficiency
  • Evidence of sepsis or metabolic disorder
  • Vomiting, Lethargy
  • Hepatosplenomegaly
  • Excess weight loss (>10%)
  • Temperature instability

Causes Of Neonatal Jaundice

Conjugated

  • Pale stools / dark urine
  • Raised conjugated bilirubin (>25% total or >25umol/l)
  • Biliary atresia
  • Choledochal cyst
  • Neonatal hepatitis (congenital infection, alpha-1 antitrypsin deficiency; often idiopathic)
  • Metabolic (galactosaemia, fructose intolerance - ask about sucrose/fructose in food/medication)
  • Complication of TPN

Unconjugated

  • Breast milk jaundice - 3-5% of breast fed babies
  • Prematurity - exaggerated physiological pattern; may last 4 weeks
  • Bruising / cephalohaematoma – breakdown of heme
  • Haemolysis (Rhesus, ABO, G6PD or PK deficiency, spherocytosis) - early onset for ABO, Rhesus
  • Sepsis - rarely presents with jaundice alone (occasional for UTI); usually unwell
  • Metabolic (eg. hypothyroidism) - prolonged jaundice, can be mixed conjugated/unconjugated
  • Polycythemia - delayed cord clamping, twin to twin transfusion
  • Gilbert / Crigler-Najjar - rare, usually present as prolonged jaundice
  • GI obstruction (eg. pyloric stenosis)

Notes

  1. Physiological jaundice. Jaundice is very commonly noted in the first 2 weeks of life. It is part of a normal physiological process and affects 50 to 70% of babies. Mild jaundice with onset after 24 hours of life and which is fading by 14 days needs no investigation or treatment
  2. Breast milk jaundice is the most common cause of prolonged jaundice but other causes should be eliminated before making this diagnosis. A breast-fed baby with prolonged unconjugated jaundice, normal stool and urine colour, normal FBE/film/Coombs who is well and thriving probably has breast-milk jaundice. Do not stop breast feeding. Suggest review in General Paediatrics clinic if not improving or any changes - especially stool colour
  3. Conjugated hyperbilirubinaemia must be excluded as the causes of this pattern need urgent evaluation and treatment. Surgery for biliary atresia is most successful when the condition is diagnosed and treated early. Don't forget to ask about the colour of urine and stools. View a dirty nappy yourself if possible
  4. Phototherapy or rarely exchange transfusion may be necessary in a baby with severe unconjugated jaundice associated with prematurity, haemolytic disease, or rare disorders such as Crigler-Najjar. Outside these conditions unconjugated jaundice is unlikely to lead to CNS or hearing problems, and no treatment is usually necessary

Breast feeding and jaundice

Breast fed infants tend to have a higher peak bilirubin and are more likely to have prolonged jaundice than formula fed babies. The higher early peak may be due to a delay in starting breastfeeds, infrequent feeding, or if positioning and attachment of the baby at the breast is not good.

  • Do not stop breast feeding (unless an exchange is likely)
  • Encourage frequent feeds (3 hourly)
  • Do not supplement with water or dextrose orally as this does not bring the bilirubin down faster
  • If supplementation is required expressed breastmilk (EBM) should be given as first choice

Most babies will improve with an increased frequency of breast feeds. Formula should only be given if EBM is not available.


Investigations early neonatal jaundice

Indications for investigation:

  • Possible haemolysis (usual onset < 24 hours of life)
  • Bilirubin rising to "Exchange Transfusion" levels
  • Sick baby with jaundice - ?sepsis or inherited metabolic disorder

Investigations:

  • Blood Groups - baby and mother
  • Direct Coombs Test
  • FBC - Hb, WBC and smear
  • Bilirubin - Total and conjugated
  • G6PD assay
  • Reducing substances (Urine)
  • Sepsis screen

Approach

Investigations prolonged neonatal jaundice

Indications for investigation

  • NNJ persisting for 14 days in term babies
  • NNJ persisting for 14 days in preterm baby
  • NNJ persisting for 14 -21 days in preterm babies receiving intensive care/TPN

Investigations:

  • Bilirubin - Total and conjugated
  • Reducing substances (Urine), Urine C&S
  • Blood Groups - baby and mother
  • TSH & T4
  • FBC - Hb, WBC, Direct Coombs test
  • Liver transaminases, G6PD Deficienc

Further investigation may be required. (eg) if conjugated hyperbilirubinaemia (conjugated fraction >20% of total bilirubin) hepatic USS, a1-antitrypsin, HIDA radionucleotide scan.


Management of jaundice in healthy term neonates

Age (hours) Consider phototherapy Must have phototherapy Exchange transfusion if intensive phototherapy fails * Exchange transfusion immediately plus intensive phototherapy
<25 N/A N/A N/A N/A
25-48 170 260 340 430
49-72 260 310 430 500
>72 290 340 430 500

*Intensive phototherapy means 2 light sources ± a biliblanket. The bilirubin should fall by at least 30mmol/l within 4 hours and should continue to fall and remain below the level for exchange transfusion.


Content by Dr Íomhar O' Sullivan. Last review Dr ÍOS 22/10/22.