Infant and Children | January 19, 2015 | Author: The Super Pharmacist
Neonatal jaundice, also known as neonatal hyperbilirubinemia, is a condition that is caused by excessive levels of bilirubin in the blood. Bilirubin is a natural yellow breakdown product that is produced when red blood cells, carrying oxygen around the body, are broken down. Usually, bilirubin is naturally excreted in faeces and urine. Excessive levels of bilirubin are responsible for the yellow discoloration that is found in neonates that have jaundice. It is estimated that 60% of term and 80% of preterm babies will develop jaundice within the first week of their life. It is also thought that 10% of babies that are still breast-fed will also remain jaundiced after the first month of their life (1).
Jaundice is common in newborn babies because they have a high level of red blood cells and their liver is not fully developed enough to fully process bilirubin and extract it from the blood. As such, levels of bilirubin are approximately double that found in the average adult. By the time a baby is two weeks old, there is often significantly less bilirubin in its body as its liver becomes more effective and processing and removing waste, at which point jaundice will often correct itself without causing any further harm.
There are a number of different complications and concerns linked to neonatal jaundice, as it can be a symptom of a wide range of other health conditions that are common in newborn babies. Early neonatal jaundice, with an onset of less than 24 hours, can be the symptom of some of the following diseases:
Haemolytic disease (where antibodies in a pregnant woman’s blood destroy the baby’s blood cells, or blood group mismatch where mother and child have different blood groups which can result in complications)
Infections: congenital (such as rubella and toxoplasmosis), postnatal (such as syphilis), or herpes.
Rarer syndromes, such as Crigler-Najjar syndrome (a disorder affecting the metabolism and breaking down of bilirubin)and Gilbert’s syndrome (a genetic liver disorder and the most prevalent hereditary cause of increased bilirubin production).
Prolonged jaundices, lasting for 14 days in term infants and 21 days in preterm infants, can be the symptom of:
Treatment is recommended for longer term jaundice to prevent a serious complication of the illness called kernicterus (2). This is a bilirubin induced brain dysfunction that can, at worst, cause permanent brain damage. It can also result in a range of other health conditions such as cerebral palsy, hearing loss, learning difficulties and higher than average levels of tooth decay (3).
All children will often be screened for jaundice within 72 hours of being born. This is usually in the form of a visual examination, under good natural light, that checks the whites of the baby’s eyes, the colour of the baby’s stool and urine, and the colour of the baby’s gums. If an initial examination results in suspected jaundice, a bilirubin test is required. This is done using a small device called a bilirubinometer that beams light onto the baby’s skin. By analysing how the skin both deflects and absorbs this light, the device can calculate the bilirubin levels in the baby’s blood. Another reading can also be gained through a blood test which can be obtained by pricking the baby’s heel with a needle.
Treatment is rarely given to most cases of neonatal jaundice as the condition will often get better on its own within 10-14 days. However, if the jaundice is prolonged and lasts for more than two weeks, further treatment may be required.
Most treatment procedures for neonatal jaundice require admittance to hospital, where a child will be treated using one of two techniques known as phototherapy or exchange transfusion.
Phototherapy involves treatment using light. The photo-oxidisation of the bilirubin converts it into a substance that dissolves easily in water, helping the baby’s liver metabolise and remove the waste product from their blood.
The two types of phototherapy:
Conventional phototherapy, where the baby is laid down under a halogen or fluorescent lamp (with their eyes covered to prevent damage)
Fibre optic phototherapy, where a baby lies on a blanket that contains fibre optic cables and shine onto the baby’s back. In both methods, the aim of phototherapy is to expose the child to as much light as is possible.
Both treatment options have a strong evidence base: a randomised controlled trial of nearly 300 children, undertaken in India in 2010, found both methods of phototherapy to be equally efficacious in the management of jaundice (4). Both methods are used until bilirubin begins to fall to a clinically acceptable level, which usually occurs within 1-2 days of treatment (5).
Exchange transfusion is a blood transfusion that is usually used as a second line treatment when phototherapy has not been effective and bilirubin levels remain excessively high (6). The process involves the removal of the baby’s blood via a small plastic tube placed into blood vessels in the arms, legs and umbilical cord. The blood is then replaced from a matching donor that does not contain bilirubin, causing the baby’s own levels to fall significantly. Whilst efficacious, phototherapy is always recommended as a first line treatment due to its safety, effectiveness and relatively few associated problems. Whilst exchange transfusion does also have a significant success rate, it is more invasive and is associated with a range of potential complications such as hypersensitivity reactions, sepsis, hypotension and catheter-induced vascular damage (7).
1. National Institute of Care Excellence Care Guidelines: Neonatal Jaundice. Available online at http://www.nice.org.uk/guidance/CG98 (last accessed 2nd January 2015)
2. Muchoswki KE. (2014). Evaluation and treatment of neonatal hyperbilirubinemia. Am Fam Physician 1:89(11):873-8
3. Cappellini MD, Di Montemuros FM, Sampietro M, Tavazzi D, Fiorelli G. (1999). The interaction between Gilbert's syndrome and G6PD deficiency influences bilirubin levels. British journal of haematology 104 (4): 928–9
4. Kumar P, Murki S, Malik GK, Chawla D, Deorari AK et al. (2010). Light emitting diodes versus compact fluorescent tubes for phototherapy in neonatal jaundice: a multi center randomized controlled trial. Indian Pediatr 47(2):131-7 Epub
5. Karadag A, Yesilyurt A, Unal S, Keskin I, Demirin H, Uras N, Dilmen U, Tatli MM. (2009). A chromosomal-effect study of intensive phototherapy versus convential phototherapy in newborns with jaundice. Mutat Res 31:676(1-2):17-20
6. Alizadeh Taheri P, Sadeghi M, Sajjadian N. (2014). Severe neonatal hyperbilirubinemia leading to exchange transfusion. Med J Islam Repub Iran 14;28:64
7. Porter ML, Dennis BL. (2002). Hyperbilirubinemia in the Term Newborn. Am Fam Physician 65:599-606