Quiz: Physiological Neonatal Jaundice — 26 questions

1. What does jaundice describe in a newborn?

A. Raised bilirubin concentration measured in the bloodstream

B. Reduced red blood cell production during early infancy

C. Brain injury caused by bilirubin entering neural tissue

D. Yellow skin and sclerae caused by bilirubin accumulation

Answer: (D)

Explanation

Jaundice is the visible yellow discoloration that results when bilirubin accumulates after red blood cell breakdown. Hyperbilirubinaemia is the raised bilirubin level underlying this sign, not the visible discoloration itself.

2. Which finding is characteristic of kernicterus?

A. Clinical features of acute or chronic bilirubin encephalopathy

B. Increased red blood cell production during fetal life

C. Yellow discoloration limited to the skin and sclerae

D. Raised bilirubin without any neurological consequences

Answer: (A)

Explanation

Kernicterus refers to neurological features of acute or chronic bilirubin encephalopathy, including cerebral palsy, hearing loss, and visual problems. Yellow skin and sclerae describe jaundice, which does not by itself establish kernicterus.

3. What proportion of term babies develops jaundice during the first week of life?

A. Approximately 20 percent

B. Approximately 80 percent

C. Approximately 40 percent

D. Approximately 60 percent

Answer: (D)

Explanation

About 60 percent of term babies develop jaundice in the first week, and it is harmless in most babies. The figure of about 80 percent applies to preterm babies rather than term babies.

4. Where are ageing, immature, or malformed red blood cells removed by phagocytosis?

A. In the bone marrow, where haemoglobin is conjugated

B. In the renal tubules, where bilirubin is filtered from plasma

C. In the intestinal lumen, where bacteria form urobilin

D. In the reticuloendothelial system, including the liver and spleen

Answer: (D)

Explanation

Phagocytosis removes abnormal or ageing red blood cells in the reticuloendothelial system, including the liver, spleen, and macrophages. Conjugation is a later hepatic modification of bilirubin rather than the process that removes red blood cells.

5. What happens to haemoglobin during its breakdown?

A. Haem forms unconjugated bilirubin, globin forms amino acids, and iron is stored or reused

B. Haem forms conjugated bilirubin, globin forms bile acids, and iron is excreted in urine

C. Haem forms urobilin, globin forms albumin, and iron is converted into glucose

D. Haem forms amino acids, globin forms unconjugated bilirubin, and iron enters the intestine

Answer: (A)

Explanation

Haem is converted into unconjugated, fat-soluble bilirubin; globin becomes amino acids; and iron is stored in the liver or used to produce new red blood cells. Conjugated bilirubin and urobilin are formed later during hepatic and intestinal processing.

6. What is the result of bilirubin conjugation in the liver?

A. Urobilin is produced directly and transported into the bloodstream

B. Water-soluble bilirubin is produced for excretion into bile and the gut

C. Red blood cells are removed through phagocytosis in liver macrophages

D. Fat-soluble bilirubin is produced for binding to albumin in plasma

Answer: (B)

Explanation

The liver uses oxygen, glucose, and enzymes to conjugate unconjugated bilirubin, making it water-soluble and suitable for excretion into bile and the gut. Albumin transport applies to unconjugated bilirubin before hepatic uptake, while urobilin forms in the gut.

7. How is bilirubin mainly processed after reaching the gut?

A. Bacteria convert it to urobilin, which is excreted in faeces, while some is reabsorbed or excreted in urine

B. Liver enzymes convert it to unconjugated bilirubin, which is stored in the spleen

C. Albumin binds it again, returning it to the liver without intestinal bacterial action

D. Macrophages convert it to iron, which is eliminated through the intestinal wall

Answer: (A)

Explanation

Gut bacteria convert conjugated bilirubin to urobilin, which is excreted in faeces; some bilirubin undergoes enterohepatic reabsorption and some is excreted in urine. The other processes occur in the bloodstream, liver, or reticuloendothelial system rather than describing gut metabolism.

8. Which globin composition distinguishes fetal haemoglobin from adult haemoglobin?

A. Fetal haemoglobin contains beta-globin pairs instead of adult gamma-globins

B. Fetal haemoglobin contains gamma-globin pairs instead of adult beta-globins

C. Fetal haemoglobin contains albumin chains instead of adult globin molecules

D. Fetal haemoglobin contains iron chains instead of adult haemoglobin subunits

Answer: (B)

Explanation

Fetal haemoglobin contains a pair of gamma-globin molecules, whereas adult haemoglobin contains beta-globins. This fetal form also binds oxygen with greater affinity, supporting oxygen transfer before birth.

9. What happens to fetal red blood cells after birth?

A. They are removed after their 70–80-day lifespan as fetal haemoglobin is replaced

B. They are removed within a few hours as albumin binding stops in the circulation

C. They persist until the liver conjugates all bilirubin produced from their haemoglobin

D. They remain for about 120 days while fetal haemoglobin increases its oxygen affinity

Answer: (A)

Explanation

At term, fetal red blood cells have a lifespan of about 70–80 days and are removed after birth as fetal haemoglobin is replaced by adult haemoglobin. Their removal contributes to bilirubin production but does not wait for complete hepatic conjugation.

10. Why does physiological jaundice commonly develop in newborns?

A. Adult haemoglobin replacement, increased renal filtration, rapid conjugation, and developed intestinal flora prevent bilirubin accumulation

B. Short-lived red cells, limited albumin binding, a sterile gut, poor peristalsis, and an immature liver affect bilirubin handling

C. Reduced red cell production, extensive bacterial conversion, strong gut motility, and efficient hepatic excretion lower bilirubin levels

D. Long-lived red cells, abundant albumin binding, rapid peristalsis, and a mature liver increase bilirubin clearance

Answer: (B)

Explanation

Newborn physiology increases bilirubin production and reduces its metabolism or excretion through several combined factors, including short-lived red cells and an immature liver. The other choices describe more efficient bilirubin handling or reverse the characteristic newborn processes.

11. When does typical physiological jaundice usually reach its peak intensity in a newborn?

A. Around the tenth day of life

B. Near the end of the first month

C. Around the fifth day of life

D. During the first day of life

Answer: (C)

Explanation

Typical physiological jaundice usually begins around day 3, peaks around day 5, and resolves by approximately day 8. Jaundice during the first 24 hours is concerning for pathology rather than the normal physiological pattern.

12. What bilirubin concentration is generally consistent with typical physiological jaundice?

A. Approximately 200–215 μmol/l or below

B. Approximately 300–325 μmol/l or below

C. Approximately 350–375 μmol/l or below

D. Approximately 250–275 μmol/l or below

Answer: (A)

Explanation

Bilirubin levels in typical physiological jaundice should not exceed approximately 200–215 μmol/l. Higher concentrations require assessment for causes beyond the usual physiological process.

13. Which finding should prompt urgent referral because jaundice is considered pathological until proven otherwise?

A. Jaundice becoming noticeable around the third day of life

B. Jaundice resolving by approximately the eighth day

C. Jaundice appearing within the first 24 hours of life

D. Jaundice peaking around the fifth day of life

Answer: (C)

Explanation

Jaundice within the first 24 hours is pathological until proven otherwise and requires immediate paediatric referral. Appearance around day 3 is more typical of physiological jaundice.

14. Which newborn has a recognised increased risk of significant hyperbilirubinaemia?

A. A baby without visible jaundice in the first day

B. A baby with no family treatment history

C. A baby born at 37 weeks' gestation

D. A baby born at 39 weeks' gestation

Answer: (C)

Explanation

Gestational age below 38 weeks is a recognised risk factor for significant hyperbilirubinaemia. The other descriptions do not identify the specific risk factor stated here.

15. Which combination is most characteristic of clinically recognisable jaundice in a newborn?

A. Pale skin, strong feeding, dark stools, and concentrated urine

B. Yellow skin, frequent feeding, dark stools, and clear urine

C. Yellow sclerae, poor feeding, pale stools, and dark urine

D. Red sclerae, vigorous feeding, pale stools, and clear urine

Answer: (C)

Explanation

Clinical recognition includes yellow skin or sclerae together with signs such as poor feeding, pale stools, or dark urine. The other combinations replace these findings with features that do not characterise neonatal jaundice in this context.

16. How should jaundice surveillance be organised during the newborn period?

A. Examine babies at discharge, with extra review during the second week

B. Examine babies once after birth, with further review if symptoms develop

C. Examine only babies born before 38 weeks during the first three days

D. Examine every baby at each opportunity, with extra review for those at risk

Answer: (D)

Explanation

All babies should be examined for jaundice at every opportunity, particularly during the first 72 hours, while those with risk factors need an additional professional examination in the first 48 hours. A single examination or risk-based screening alone does not meet this approach.

17. Why should visual inspection of jaundice not be used to estimate bilirubin severity?

A. Cephalocaudal progression identifies treatment thresholds without blood testing

B. Skin colour changes are unrelated to jaundice and require urine testing

C. The visible distribution does not reliably predict the bilirubin concentration

D. Jaundice spreads from the feet upward and usually underestimates concentration

Answer: (C)

Explanation

Jaundice commonly progresses from the head toward the feet, but this visual pattern is a poor predictor of bilirubin severity. Serum or appropriate bilirubin measurement is needed to assess the concentration and guide management.

18. A baby is over 24 hours old, was born at 36 weeks, and has suspected jaundice. What measurement approach is appropriate?

A. Use a transcutaneous bilirubinometer and confirm a reading above 250 μmol/l with serum testing

B. Rely on visual inspection and obtain serum testing only if jaundice reaches the feet

C. Use a transcutaneous bilirubinometer and accept readings above 250 μmol/l without confirmation

D. Wait until the baby reaches 38 weeks' corrected age before measuring bilirubin

Answer: (A)

Explanation

For babies over 24 hours old with gestational age of at least 35 weeks, transcutaneous measurement can be used, but readings above 250 μmol/l require serum confirmation. Visual inspection cannot establish severity, and delaying assessment is inappropriate.

19. A newborn older than 24 hours has suspected or obvious jaundice. How quickly should serum bilirubin be measured?

A. Within forty-eight hours, after repeating the visual examination

B. At the next routine visit, if the jaundice remains visible

C. Urgently, within six hours, to guide management

D. Within twelve hours, after observing the feeding pattern

Answer: (C)

Explanation

Serum bilirubin should be measured urgently within 6 hours in babies over 24 hours old with suspected or obvious jaundice, and the result should determine management. Delaying measurement risks postponing appropriate treatment decisions.

20. What neurological problem results from unconjugated bilirubin toxicity in the brain and spinal cord?

A. Bilirubin encephalopathy

B. Respiratory distress syndrome

C. Conjugated hyperbilirubinemia

D. Neonatal hypoglycemia

Answer: (A)

Explanation

Bilirubin encephalopathy is neurological dysfunction caused by the toxic effects of unconjugated bilirubin on the brain and spinal cord. Conjugated bilirubin is not identified here as the form that crosses the blood–brain barrier and causes this injury.

21. At which serum bilirubin concentration is kernicterus most likely, with prematurity increasing the risk?

A. Above 350 μmol/l

B. Above 300 μmol/l

C. Above 250 μmol/l

D. Above 450 μmol/l

Answer: (A)

Explanation

Kernicterus is most likely when serum bilirubin exceeds 350 μmol/l, and prematurity or other risk factors can increase susceptibility. The 450 μmol/l value refers to the stated exchange transfusion threshold rather than the level most associated with kernicterus risk.

22. Which combination meets the stated risk criteria for a baby born at more than 37 weeks' gestation?

A. Bilirubin above 450 μmol/l or rising at 6.5 μmol/l per hour

B. Bilirubin above 340 μmol/l or rising at 8.5 μmol/l per hour

C. Bilirubin above 350 μmol/l or rising at 5.0 μmol/l per hour

D. Bilirubin above 300 μmol/l or rising at 10.5 μmol/l per hour

Answer: (B)

Explanation

The risk criteria include serum bilirubin above 340 μmol/l in babies over 37 weeks' gestation and a rapid rise of 8.5 μmol/l per hour. A level above 350 μmol/l is associated with kernicterus risk, but it is not the specific threshold paired with this rate criterion.

23. What serum bilirubin concentration is the stated threshold for exchange blood transfusion?

A. 340 μmol/l

B. 450 μmol/l

C. 250 μmol/l

D. 350 μmol/l

Answer: (B)

Explanation

The stated threshold for exchange blood transfusion is 450 μmol/l. Lower concentrations describe risk criteria or increased kernicterus risk rather than the exchange transfusion threshold.

24. A term baby remains jaundiced for 15 days. Which assessment is appropriate for prolonged jaundice?

A. Start exchange transfusion assessment because any jaundice beyond two weeks indicates kernicterus

B. Continue routine observation because prolonged jaundice begins after three weeks in term babies

C. Assess stool and urine colour, measure conjugated bilirubin, investigate blood and urine, and confirm metabolic screening

D. Measure unconjugated bilirubin alone and postpone urine testing until feeding becomes inadequate

Answer: (C)

Explanation

For babies born at 37 weeks or more, jaundice lasting beyond 14 days requires assessment of stool and urine colour, conjugated bilirubin measurement, blood and urine investigations, and confirmation of routine metabolic screening. The three-week threshold applies to babies born before 37 weeks, not term babies.

25. Which description best defines breastmilk jaundice?

A. Normal persistence of unconjugated hyperbilirubinaemia into the third or later week in a healthy breastfed newborn

B. Early jaundice caused by inadequate caloric intake and excessive neonatal weight loss

C. Conjugated hyperbilirubinaemia caused by biliary obstruction in a newborn receiving breast milk

D. Neurological dysfunction caused by bilirubin crossing into the central nervous system

Answer: (A)

Explanation

Breastmilk jaundice is a normal, recurring persistence of unconjugated hyperbilirubinaemia into the third and later weeks in an otherwise healthy breastfed newborn. Poor feeding can worsen bilirubin levels through insufficient calorie intake, but that mechanism describes breastfeeding jaundice rather than breastmilk jaundice.

26. How should breastfeeding generally be managed when a newborn has neonatal jaundice?

A. Reduce feeding frequency so that bilirubin production decreases during the first weeks

B. Stop breastfeeding temporarily because breast milk commonly causes dangerous bilirubin accumulation

C. Replace breastfeeding with water feeds until the bilirubin concentration returns to normal

D. Continue breastfeeding while optimizing feeds to limit early weight loss and promote early weight gain

Answer: (D)

Explanation

Breastfeeding can usually continue during neonatal jaundice, and effective feeding that limits early weight loss and supports early weight gain is associated with less breastfeeding jaundice. Stopping feeds or giving water does not reflect the recommended general approach and may worsen inadequate nutrition.