Jaundice is defined as the yellowish tint of the skin, mucous membranes and secretions due to an increase in bilirubin in the blood (a product resulting from the degradation of red blood cells in the liver). This increase in bilirubin occurs because the newborn’s liver cannot eliminate it through the intestine and it accumulates in the bloodstream. In pregnancy, the placenta removes the bilirubin from the baby and it is the mother’s liver that is responsible for processing the bilirubin and eliminating it through the feces.
Neonatal jaundice is usually a mild disorder and resolves without treatment. It is what is called “physiological jaundice”, which appears between the second and third day and resolves in two weeks. In this case the baby is healthy and without disease.
Approximately 60% of healthy newborns have jaundice; This begins in the head and face and then extends to the trunk and extremities (from head to feet). You can easily see if the color of the skin whitens when you press it with your finger. When jaundice decreases, it does so in the opposite direction to its appearance: from head to toe.
In other cases, jaundice can be a sign of illness in the newborn.
The appearance of jaundice in the healthy newborn is due to:
- Hemoglobin concentration decreases sharply during the first days of life, eliminating a large amount of bilirubin that the liver cannot eliminate.
- The life of the erythrocytes (red blood cells) is shorter than in adults and their degradation originates large amounts of bilirubin.
- Liver function is very inefficient in the first days of life.
Jaundice is an aspect to control for two reasons:
- It can be a sign of a serious illness: infection or blood group incompatibility.
- An excess of unconjugated bilirubin in the blood can be deposited in the brain and cause serious neurological damage: cerebral palsy and deafness.
The age of onset of jaundice in the newborn is a key guide to knowing the probable cause of jaundice:
Jaundice beginning in the first 24 hours of life:
- Congenital infections: cytomegalovirus, herpes, rubella, syphilis, toxoplasmosis…
- Hemolytic processes: these are diseases that cause the massive destruction of red blood cells. In these cases, bilirubin levels can be very high and cause brain damage, so early diagnosis is very important.
- Incompatibility of blood groups (see section).
- Glucose-6-phosphate-dehydrogenase deficiency (G6PD): disease that consists of the deficiency of an enzyme present in red blood cells (G6PD) and that makes them sensitive to being destroyed by some drugs and the ingestion of beans.
- Spherocytosis: sphere-shaped red blood cells that make them very fragile, so they break easily.
Jaundice that begins between two days and two weeks of life:
- Physiological jaundice: it is a normal process that affects more than half of newborns; It is not associated with any health problems and resolves without treatment by two weeks of age. It is due to immaturity of liver function. It is the most common cause of jaundice in the newborn.
- Breastfeeding jaundice: is another common form of newborn jaundice that does not represent seriousness. The cause of this hyperbilirubinemia is not clear. The yellowish tint on the baby’s skin can last up to two months but it has no repercussions for his health. The mother can continue to breastfeed her child with complete peace of mind.
- Infection: sepsis, urine infection, pneumonia…
- Polycythemia: presence of high levels of red blood cells. It is more common in premature infants.
Jaundice that begins with more than two weeks of life:
- Breastfeeding jaundice: the baby does not cause problems.
- Congenital hypothyroidism.
- Bile duct atresia: is an obstruction of the ducts that carry bile from the liver to the gallbladder.
- Hepatitis neonatal.
In cases of physiological jaundice and breastfeeding, no treatment is necessary, since it is a normal state of the baby and they resolve spontaneously.
The most common treatment for jaundice caused by disease is exposure of the newborn to ultraviolet light (phototherapy). The child is placed under an ultraviolet lamp for a few hours a day. UV light breaks down bilirubin and helps the baby’s liver get rid of it.
When bilirubin rises to levels considered dangerous or phototherapy is not effective, an exchange transfusion is performed. It consists of extracting blood through the baby’s umbilical vein and replacing it with donor blood.