Jaundice in newborns is a common condition that requires accurate diagnosis to distinguish between physiological and pathological causes.
Early and correct testing helps spot serious health problems. This way, babies get treated before complications appear. To make the diagnosis of jaundice in newborns, doctors use several steps. These include looking at the baby, checking risk factors, measuring bilirubin, and sometimes doing lab tests or scans.
Jaundice can be harmless, but it can also point to serious issues in the liver, blood, or metabolism. So, a clear testing plan is key. Many hospitals now use standard screening to find it early and protect the baby’s health.
Clinical Observation and First Clues
Doctors start by looking at the baby’s skin and eyes. Yellow skin and eyes often show up when bilirubin rises above 5–7 mg/dL (85–120 µmol/L). The yellowing starts at the face and moves downward to the body and limbs.
Even though this check is helpful, it’s not always enough. Light and skin colour can make it hard to see the yellow tint. So, doctors also look at other signs.
They also note:
- Baby’s age in hours
- How often and how well the baby feeds
- Colour of urine and poop
- Baby’s activity and alertness
If yellowing starts in the first 24 hours, it’s not normal. It may mean an infection, a blood issue, or a liver problem. Immediate testing is needed.
Transcutaneous Bilirubinometry (TcB)
A fast and easy way to check bilirubin is through TcB. This test uses a small device placed on the baby’s head or chest. It measures light through the skin to estimate bilirubin.
While not perfect, TcB gives quick results and avoids blood draws. It works well for routine checks and follow-ups.
However, TcB may not be accurate in babies with dark skin, high bilirubin levels, or liver problems. If results are near the danger level, doctors will ask for a blood test.
Total Serum Bilirubin (TSB) – The Key Test
The best way to confirm diagnosis of jaundice in newborns is by testing the baby’s blood. Doctors take a small sample from the heel or vein and send it to the lab.
This test:
- Shows exact bilirubin levels
- Tells if bilirubin is direct (conjugated) or indirect (unconjugated)
- Helps tell normal jaundice from serious types
Doctors place the results on a chart that matches the baby’s age and risk level. These charts help them decide if treatment like phototherapy or a blood change is needed.
Understanding Bilirubin Fractions
To find the cause of jaundice, doctors check if bilirubin is indirect or direct.
- Indirect bilirubin rises in normal jaundice, breastfeeding issues, or when red blood cells break down too fast.
- Direct bilirubin goes up in liver disease, blocked bile flow, or hepatitis.
High direct bilirubin always needs further tests. If it’s above 1 mg/dL or more than 20% of the total, the baby must get checked right away.
More Tests to Support Diagnosis
If jaundice shows up early, lasts long, or seems worse than usual, more lab work is needed.
a. Full Blood Count (FBC)
- Checks for infection, too many or too few red blood cells
- Shows cell shape and size
b. Blood Group and Coombs Test
- Matches mother’s and baby’s blood types
- Coombs Test finds antibodies stuck to red cells, a sign of blood-type issues
c. Reticulocyte Count
- Checks how well the bone marrow makes red cells
- Goes up in blood cell breakdown problems
d. G6PD Screening
- Finds a common enzyme problem in some groups
- Helps explain why jaundice appears
e. Thyroid Function Tests
- Checks for low thyroid, which can cause long-lasting jaundice
f. Liver Function Tests (LFTs)
- Looks at how well the liver works
- Helps spot hepatitis or blocked bile flow
Urine and Stool Checks
In babies with lasting jaundice, pee and poop colour give big clues. Dark pee and pale poop may show blocked bile flow or liver trouble.
Doctors may also test urine for infection, as this can cause jaundice too. The shape, colour, and frequency of the baby’s poop are key when checking for biliary atresia. This condition needs fast surgery to prevent damage.
Imaging in Diagnosis of Jaundice in Newborns
Once doctors confirm high direct bilirubin, they order scans.
a. Abdominal Ultrasound
- Looks at liver, gallbladder, and bile tubes
- Finds problems like blocked bile ducts
b. HIDA Scan
- Shows how well bile flows
- Helps tell blocked ducts apart from liver swelling
c. MRI
- Sometimes used in tricky cases
- Gives a closer view of the liver or brain
Genetic and Metabolic Testing
If jaundice doesn’t go away or comes with other signs like poor feeding, slow growth, or vomiting, rare disorders may be to blame.
Doctors may suggest:
- Metabolic panels for newborns
- Tests for galactosemia
- Alpha-1 antitrypsin levels
- Chromosome studies
These tests help uncover hidden problems and usually need advice from specialists.
Brain Checks for Severe Cases
If jaundice gets really bad or goes untreated, the brain may suffer. Signs like odd body movements or seizures mean urgent action.
Doctors may order:
- Brain scans
- EEG tests
- MRI of the brain
These tests look for kernicterus or other damage.
Routine Screening for Better Outcomes
Many countries now check all babies for jaundice before they leave the hospital. This check happens in the first 72 hours and includes either TcB or TSB.
Babies who are at high risk get follow-up appointments. Parents also learn how to spot warning signs.
Babies going home before 48 hours need to see a doctor again within 2 or 3 days. This helps catch problems early.
Conclusion: Importance of Diagnosis of Jaundice in Newborns
The diagnosis of jaundice in newborns needs more than just a look at the baby’s skin. While seeing the yellow colour is helpful, blood tests and scans confirm how serious it is.
Advanced tools and expert advice help find the cause when usual checks fall short. Quick testing helps prevent harm and allows early treatment.
With strong screening plans, good follow-up, and easy access to tools, doctors can spot and treat jaundice well. This protects the baby’s brain and body during a critical stage.
