What causes jaundice in children?

Jaundice is actually a very common disease in children, so parents don’t need to be too nervous. There are several causes of jaundice. For example, the oxygen content in the fetus's uterus is relatively low, which can easily lead to increased bilirubin after birth. Another cause is breast milk jaundice, which means the jaundice in breast milk exceeds the normal value.

1. Physiological jaundice

Neonatal physiological jaundice is a phenomenon unique to the neonatal period. Because the fetus is in the hypoxic environment in the uterus, there is excessive production of red blood cells in the blood. These red blood cells are mostly immature and easily destroyed. After the fetus is born, excessive bilirubin is produced, which is about twice that of adults. On the other hand, the immature liver function of the newborn restricts the metabolism of bilirubin, which causes jaundice in the newborn for a period of time.

Physiological jaundice begins on the 2nd to 3rd day of full-term infants. At this time, the skin is light yellow, the sclera (white of the eye) is mainly blue with a slight yellow tint, the urine is slightly yellow but does not stain the diaper. It is the yellowest on the 4th to 5th day and disappears on the 10th to 14th day of full-term infants. Liver function tests show normal results and increased serum unconjugated bilirubin. Physiological jaundice in premature infants will appear earlier, be higher, and last longer, and may be delayed to disappear in 3 to 4 weeks. Although the child has jaundice, he does not feel any discomfort and is in generally good condition. Physiological jaundice is a normal physiological phenomenon and does not require treatment.

2. Breast milk jaundice

Jaundice in newborns due to breastfeeding is called breast milk jaundice, which is a special type of pathological jaundice. In a small number of breastfed newborns, the degree of jaundice exceeds normal physiological jaundice, and the reason is not very clear. The characteristics of jaundice are: after the peak of physiological jaundice, the jaundice continues to worsen. If breastfeeding continues, the jaundice will continue at a high level for a period of time before slowly decreasing. If breastfeeding is stopped for 48 hours, the jaundice will obviously decrease. If breastfeeding resumes, the jaundice will increase again. Because breast milk contains the hormone pregnanediol, it can inhibit the activity of glucuronyl transferase in the liver of the newborn, causing the bilirubin in the blood to not be metabolized and excreted in time. As a result, the bilirubin concentration in the blood increases, resulting in yellowing of the newborn's skin and sclera.

Breast milk jaundice generally does not affect the health of the child, and there are no symptoms of fever or loss of appetite. If breastfeeding is stopped in time, jaundice will weaken in about 2-4 days and disappear completely within 6-10 days. Breast milk jaundice generally does not cause damage to the nervous system. There is no need to panic about breast milk jaundice. When breastfeeding is stopped, milk can be used as a temporary substitute, and breastfeeding can be continued after the jaundice improves.

3. Hemolytic jaundice

The most common cause of hemolytic jaundice is ABO hemolysis, which is caused by the incompatibility of the blood types of the mother and the fetus. The most common case is when the mother's blood type is O and the fetus's blood type is A or B, and the jaundice caused is more severe; other cases include when the mother's blood type is A and the fetus's blood type is B or AB; the mother's blood type is B and the fetus's blood type is A or AB, which are less common and the jaundice caused is milder. It is reported that the incidence of ABO blood incompatibility hemolytic disease in newborns is 11.9%. Neonatal hemolytic jaundice is characterized by the onset of jaundice within 24 hours after birth and its gradual worsening. In the early stage, exchange transfusion therapy can be performed. If the symptoms are mild due to ABO blood type, phototherapy can be used.