Neonatal jaundice is not new to us, some of it is a normal physiological phenomenon, while others are caused by certain diseases. Among these diseases that cause jaundice in newborns, biliary atresia is one of the more dangerous conditions that can eventually lead to liver failure if left untreated. Some babies with biliary atresia develop jaundice in the first few days of life and are often misdiagnosed as having physiologic jaundice, which delays treatment. So new moms and dads, how can you tell if your baby’s jaundice is normal? If the jaundice persists, must the baby have biliary atresia? Physiological jaundice usually appears on the 3rd day after birth, peaks around 7 days and subsides around 10 days, and the indirect bilirubin (IBIL) in the blood test is elevated, while the direct bilirubin (DBIL) is usually not elevated; if the jaundice does not subside for 10 days or even 2 weeks, parents must be alert and need to visit the hospital to rule out pathological jaundice due to various medical and surgical causes. If jaundice persists, what diseases might the baby have? If, in the course of jaundice, the examination reveals that the baby’s direct bilirubin is elevated and exceeds 50% of the total bilirubin (TBIL), the condition is diagnosed as cholestatic jaundice, commonly known as obstructive jaundice. There are two common causes of biliary atresia and neonatal hepatitis syndrome (neonatal hepatitis syndrome is caused by biliary obstruction due to thick, stagnant bile or sediment-like stones, which will slowly subside once the bile duct is unblocked). How to distinguish biliary atresia from neonatal hepatitis syndrome? Laparoscopic exploration + cholangiography is the gold standard for differentiating biliary atresia from neonatal hepatitis syndrome, which cannot be accurately distinguished by non-surgical methods. For example, ultrasound can only make a preliminary determination to differentiate between the two. If the ultrasound shows a large gallbladder and a thick common bile duct, the baby’s extrahepatic biliary system is normal, in which case the jaundiced baby is more likely to have neonatal hepatitis syndrome; conversely, if the ultrasound reveals a small gallbladder, or even invisible gallbladder, or a fibrous plate is seen in the hilum, then biliary atresia is more likely. However, bile caused by other reasons cannot be drained into the gallbladder and the gallbladder can atrophy, so ultrasound alone cannot confirm the diagnosis of biliary atresia. Iodine 131 isotope ECT imaging can rule out biliary atresia. If the isotope can be detected in the intestine, the bile duct is clear and biliary atresia can be ruled out; if the isotope marker collects in the liver and the isotope is not detected in the intestine, the diagnosis is complete biliary obstruction, but the diagnosis of biliary atresia or other causes of biliary obstruction still cannot be confirmed. Laparoscopic cholangiography clearly shows the structure of the biliary tract and is currently the standard test for definitive biliary atresia. Once biliary atresia is diagnosed, a liver biopsy can be done to assess the extent of hepatocellular lesions (whether cirrhosis is present) and to develop a surgical treatment plan; for children with non-biliary atresia diagnosed by imaging, unnecessary major surgery can be avoided. Finally, we remind young mothers and fathers that the typical symptoms of biliary atresia include, in addition to jaundice, white stools, deepened urine color, and even a strong tea color. Therefore, if your baby has such symptoms and all tests are in favor of biliary atresia, it is best to have a laparoscopy + cholangiogram as soon as possible to clarify the diagnosis so as not to delay and aggravate the condition.