Neonatal Jaundice Flashcards
What can high levels of bilirubin can result in permanent brain damage.
What is the medical term?
Where does it deposit and what is the main sequelae of this?
Kernicterus
When the bilirubin that is binded to albumin is saturated (conjugated), unconjugated bilirubin, which is insoluble in water and soluble in lipids, crosses the BBB and deposits into the basal ganglia causing
Choreoathetoid cerebral palsy (dyskinetic)
hypotonia
seizures
semi-comatose
high pitch/weak cry
What is the tetrad of chronic sequelae of bilirubin encephalopathy or Kernicterus
1) Motor: Motor delay and Choreoathenoid cerebral palsy
2) Oculo-motor: Upward gaze
3) Cochlear: Sensorineural deafness
4) Intellectual: mild cognitive impairment
Neonatal hyperbilirubinemia or jaundice is the Yellow discoloration of the skin, sclera and mucous membranes due to accumulation of bilirubin in extravascular tissue. State the causes of Jaundice in neonates
1) Excessive RBC destruction (immune-mediated hemolysis, Polycythemia, RBC structural defects)
2) Sepsis and drugs
3) Decreased conjugation (prematurity, Gilbert’s syndrome - enzyme defects)
4) Decreased elimination (liver hypo perfusion, biliary obstruction, sepsis, intestinal obstruction)
5) Breast milk jaundice
What is the main cause of immune-related hemolysis in the newborn?
blood group mismatch
rhesus disease
What is the pathophysiology of jaundice starting from the breakdown of an RBC including how it affects the brain, re-uptake by gut, pee and poo.
The breakdown product of haemoglobin is unconjugated bilirubin (indirect bilirubin), which is insoluble in water but soluble in lipids. It is carried in the blood bound to albumin. When the albumin binding is saturated, free unconjugated bilirubin can cross the blood–brain barrier, as it is lipid soluble. Unconjugated bilirubin, previously bound to albumin, is taken up by the liver and conjugated by glucuronyl transferase to conjugated bilirubin (direct bilirubin), which is water soluble and excreted in bile into the gut and then as stercobilinogen and urobilinogen. Some bilirubin in the gut is converted to unconjugated bilirubin and reabsorbed via the enterohepatic circulation to and metabolized in the liver or excreted in urine giving dark urine
you are called into review a jaundiced neonate <24 hours of age, what is your suspected cause? (2)
Congenital infection
Hemolytic disorder (Rh, ABO, G6PD)
you are called into review a jaundiced neonate <2 weeks of age, what is your suspected cause? (4)
Breast milk jaundice
Infection (e.g. UTI)
Polycythemia
Hemolytic disorder (Rh, ABO, G6PD)
you are called into review a jaundiced neonate >2 weeks of age and is producing a very dark urine and pale stools. what is your suspected cause?
conjugated disease
Bile obstruction e.g. billiary atresia
Neonatal hepatitis
you are called into review a jaundiced neonate >2 weeks of age and is producing normal urine color what is your suspected cause?
Breast milk jaundice
Infection
Hypothyroidism
High GI obstruction (e.g. pyloric stenosis)
Hemolytic anemia (Rh, ABO, G6PD)
What is meant by “direct” bilirubin level?
The amount of conjugated bilirubin
Jaundice <24 hours is always considered to be…
Pathological and needs urgent investigation and close monitoring.
Physiological jaundice typically occurs between 2-5 days after birth.
What is physiological jaundice?
Is it typically conjugated or unconjugated?
Do they typically have neurological sequalae?
Infants have more rbcs (high hematocrit) of lower lifespan and an immature hepatic and elimination pathway => harder to clear also (+bruising during delivery). This will cause a transient buildup of broken down rbcs => more bilirubin.
It is typically unconjugated (indirect)
No neurological sequalae
What are the main causes of pathological jaundice?
When do these most likely occur?
Is it typically conjugated or unconjugated?
Is it typically prolonged or short term elevation in bilirubin levels?
Pathological until proven otherwise if <24 hrs. These are usually due to severe hemolysis (Rh, ABO, G6PD) where IgG antibodies are produced or congenital infection (TORCH)
Typically unconjugated
Typically prolonged (>14 days)
Give 3 ways to find how much bilirubin is present?
bilimeter - transcutaneous bilirubin
SBR - Serum bilirubin conjugated and unconjugated
DCT - Direct Coombe’s Test
What main parts of the history that are significant for jaundice in an otherwise normal newborn (no congenital heart defects etc..) ?
Family hx of jaundice, anemia, splenectomy, G6PD
Ethnicity
Must know! Ongoing hemolysis (mom and baby ABO and RH status)
Feeding and voiding history (all the details)
What is the typical scenario of rhesus disease? Mom is Rh? Baby is Rh?. What will happen on exposure
Typically it is a RhD -ve women carrying a RhD +ve fetus. On exposure (typically secondary to feto-maternal hemorrhage), the IgG antibodies of the mother will cross at attach to rbcs of the fetus => hemolysis
Every subsequent pregnancy is worse due to increasing levels of IgG with each exposure. What is a major complications to the fetus in mothers exposed to a Rh+ve fetus?
Erythroblastosis fetalis/fetal hydrops
How would you prevent Hemolytic anemia of the newborn?
Screen for Rh -ve mothers via serology for D IgG antibodies (3rd trimester).
Prevent sensitization: If Rh-ve, give Anti-D immunoglobulin IM after delivery or miscarriage
Fetal Hydrops (Erythroblastosis fetalis)
What are the clinical signs?
What investigations would you perform?
How would you manage a baby with acute onset jaundice postpartum?
Clinical signs:
Severe early onset jaundice
Hepatosplenomegaly
Heart failure (oedema and !ascites!)
Hemolytic anemia
Investigation:
Bilirubin levels: SBR conjugated and unconjugated, DCT
Mother and fetus/baby ABO and Rh status (2 separate tests)
Bloods: Reticulocytotic (best indicator of new rbc production => indicates hemolytic anemia)
Other bloods to always to: TFTs, blood glucose, LFTs
Management:
ABCD!!! and resuscitation
Check cord bloods
Transfer to NICU and conduct serial bilirubin measurements (to track if management is working (decline) or not)
IVIG
!Phototherapy!
Exchange transfusion not carried out but is an option
Note: Same workup for ABO and G6PD deficiency but much milder disease => assess need for resus.
Dx: Mild, early onset unconjugated jaundice
Moderate/severe, early onset unconjugated jaundice
How would you treat any of these if they were otherwise found antenatally
Moderate, late onset conjugated jaundice
How might you diagnose this?
1) Hemolytic anemia due to ABO or G6PD deficiency
No indication antenatally
2) Hemolytic anemia of the newborn
Anti-D immunoglobulin
3) Biliary atresia or neonatal hepatitis
HIDA scan (Hepatobiliary iminodiacetic acid) imaging
Polycythemia is a cause of jaundice. What is considered polycythemia in the first week of life?
Hematocrit >65%
An infant of a diabetic mother is born with reddish pinkish skin and a non-dilated abdomen. What is your likely diagnosis? What are other causes of this?
Polycythemia (note the abdomen is not distended but can be as this is a cause of nec enterocolitis)
Other causes: Chronic intrauterine hypoxia (the compensation of that after birth is what causes polycythemia)
Also delayed cord clamping
What are clinical features of polycythemia. How would you manage this patient if symptomatic?
Clinical:
Neurological (lethargy, jittery)
Cardioresp (transient tachypnea of the newbown)
GIT (Hypoglycemia (diabetic mother RF), jaundice, necrotizing enterocolitis)
How would you judge bilirubin levels in a neonate?
AKA what factors influence normal bilirubin levels
Hour of life
Gestation
Rate of rise
taking into account physiological factors of brain entry, excessive production and diminished excretion
What are the measures you may want to employ to prevent jaundice in the newborn? (2)
Anti D immunoglobulin (If scan verifies RhD -ve)
Early and frequent feeding to decrease enterohepatic circulation and increase bilirubin excretion in stool
What is the very general treatment of jaundice in the neonate?
Ensure adequate hydration
Phototherapy (conjugates bilirubin for the liver)
IVIG therapy
Seizures + jaundice. What do you give?
Phenobarbitone
Is phototherapy used for conjugated or unconjugated jaundice and why? What might happen if the other option was done?
What are some side effects of phototherapy? (2)
Phototherapy is used in unconjugated jaundice as it conjugated bilirubin instead of the liver and hence assisting with excretion from the system (conjugated is water soluble). If it was given to a conjugated jaundice patient, it may cause Bronze Baby Syndrome => never give it to a baby with dark urine or pale stools
Dehydration (ensure hydration!!)
Hyperthermia
decreased time spent with mother
A colleague suggests exchange transfusion for a jaundiced child.
What is it? What is meant by double transfusion
When is it most beneficial?
What are the risks?
Small amounts of neonate’s blood is replaced with donor blood. If double, => double of the baby’s volume is replaced.
It is most beneficial in cases of ongoing hemolysis (partial use in polycythemia)
Risks: Portal vein thrombosis => thrombocytopenia, graft vs host disease, Nec ent, infection…
Breast milk jaundice is a diagnosis of exclusion. They typically present 2-3 weeks later and are otherwise completely healthy.
Why does breast milk cause jaundice?
What treatment is required?
Breast milk causes jaundice as some contituents may inhibit conjugation in the liver.
No treatment is required as it usually regresses by 3 months. If severe maybe suggest mixed formula/breast milk or switching to formula. If you wanna be safe just say refer to lactation consultant
Delayed presentation of jaundice with acholic stools:
What is acholic stools
What is the most likely diagnosis?
How can you prove it?
What treatment is required?
Delayed presentation of jaundice with pale stools:
What is the most likely diagnosis?
What can cause this?
Acholic stools are completely white and not just paler
dx: biliary atresia
HIDA scan (Hepatobiliary iminodiacetic acid) imaging
Tx: Kasai procedure
Neonatal hepatitis
Infections or metabolic causes such as alpha-1 antitrypsin deficiency
What is the most common form of biliary atresia?
Extrahepatic
A 3 week baby presents to you with a fever and jaundice. You suspect an infection. What infection are you suspecting (type, not organism)
What if the baby didnt have a fever? What would you be suspecting?
UTI
No fever? Breastfed? If so probably breast milk jaundice. If not, congenital hypothyroidism
