Patient Presentation
A 36-hour-old, 38 6/7 week male in the newborn nursery was noted to be more yellow in his skin color. He was acting well, and attempting to breastfeed. He had had 2 wet diapers and 1 stool since birth. He was a first baby for the parents and the mother was A+ and baby was 0+. Coombs testing was pending. The total cutaneous bilirubin was 10.2 mg/dL which was above the instrument’s threshold for accuracy and also the recommendations for serum testing. A repeated serum total bilirubin was 12.8 mg/dL which was above the threshold of 12.4 mg/dL for starting phototherapy.

The pertinent physical exam showed a healthy male who was jaundiced. Birth weight was 3473 grams and currently was 3299 grams at 24 hours (down 5%). His exam was otherwise normal.

The diagnosis of hyperbilirubinemia was made. The new intern said that she had not ordered phototherapy before and wasn’t sure how many lights to order. “That’s a good question. I don’t work in the newborn nursery a lot, but the notes I see from lots of babies who I see after discharge usually have 3 or 4 lights ordered along with a biliblanket to be put underneath them. We have to order the nurses to use an isolette so hypothermia doesn’t become an issue. The nurses still monitor the temperature closely though in the isolette. Why don’t we check with the nursing staff who do this a lot, and then if we still aren’t sure then we can call on the neonatologists. I know that we do intense treatment which usually means less time the baby needs to be treated,” he replied. The patient’s clinical course showed that the nursing staff recommended to use 3 lights along with the biliblanket, and after 12 hours of therapy, the bilirubin level was down and remained down 6 hours after the phototherapy was discontinued. He was discharged with followup in 1 day in the outpatient setting.

Discussion
Bilirubin is a metabolite of heme degradation. Heme is oxidized to biliverdin which is then reduced to bilirubin. Bilirubin is then taken up into the liver and conjugated; conjugated bilirubin is then excreted through the gastrointestinal tract. Bilirubin can also be converted by a blue light at wavelength 450 nm into a water-soluble compound called lumirubin which is then excreted through the kidneys.

The differential diagnosis of neonatal unconjugated hyperbilirubinemia can be reviewed here.

Learning Point
Phototherapy treatment for hyperbilirubinemia has been used as standard of care for hyperbilirubinemia of infancy for many years with many studies have attempted to quantify the optimal treatment. The American Academy of Pediatrics 2022 Clinical Guidelines states that: “[t]he effectiveness of phototherapy is dependent on the intensity of phototherapy administered and the surface area of the infant exposed to phototherapy (ie, double-sided). Unfortunately, no standard method for delivering phototherapy exists and there is substantial variation in phototherapy equipment.”

They further state, “[c]omprehensive information about phototherapy, including its mechanism of action and strategies for its use, can be found in the Appendix to the 2004 guideline, a technical report of the AAP Committee on Fetus and Newborn, and comprehensive recent reviews. The general approach is to provide intensive phototherapy to as much of the infant’s surface area as possible. Intensive phototherapy requires a narrow-spectrum LED blue light with an irradiance of at least 30 mW/cm² per nm at a wavelength around 475 nm. Light outside the 460 to 490 nm range provides unnecessary heat and potentially harmful wavelengths. The advantage of intensive phototherapy is that it can quickly lower the [total serum bilirubin] and should shorten the duration of treatment.”

A British Medical Journal Clinical Evidence Review also stated that, “It is generally accepted that intensive phototherapy applied to infants with already high serum bilirubin levels or rapidly rising serum bilirubin levels has greatly reduced the need to exchange transfusion in infants with or without haemolysis.”

Sunlight could be used as a potential treatment. However it caries risk of dehydration, sunburn, and hypothermia. Even with sunlight filters hypothermia continues to be a major issues.

A Cochrane Collaboration review found that “Sunlight may be an effective adjunct to convention phototherapy in [low or middle income countries] settings, may allow for rotational use of limited phototherapy machines and may be preferable to families as it can allow for increased bonding. Filtration of sunlight to block harmful ultraviolet light and frequent temperature checks for babies under sunlight may be warranted for safety. Sunlight may be effective in preventing hyperbilirubinemia in some cases, but these studies have not demonstrated that sunlight alone is effective for the treatment of hyperbilirubinemia given its sporadic availability and the lower or very low certainly of the evidence in these studies.”

The American Academy of Pediatrics reiterates this information stating: “[a]lthough direct exposure to sunlight has been shown to decrease [total serum bilirubin] concentrations, the practical difficulties involved in safely exposing infants to the sun, either inside or outside, while also avoiding sunburn preclude the use of sunlight as a reliable therapeutic tool, and therefore, it is not recommended. Although filtered sunlight has been safely used in resource-constrained settings where phototherapy is not readily available, these guidelines were not developed for use in such settings.””

Questions for Further Discussion
1. What causes direct hyperbilirubinemia? A review can be found here
2. What screening testing is recommended routinely for newborn infants?
3. What causes hyperbilirubinemia in an older infant or child?

Related Cases

Disease: Jaundice

Symptom/Presentation: Jaundice

Specialty: General Pediatrics | Neonatology

Age:Newborn

To Learn More
To view pediatric review articles on this topic from the past year check PubMed.

Evidence-based medicine information on this topic can be found at SearchingPediatrics.com and the Cochrane Database of Systematic Reviews.

Information prescriptions for patients can be found at MedlinePlus for this topic: Jaundice

To view current news articles on this topic check Google News.

To view images related to this topic check Google Images.

To view videos related to this topic check YouTube Videos.

Woodgate P, Jardine LA. Neonatal jaundice: phototherapy. BMJ Clin Evid. 2015;2015:0319.

Horn D, Ehret D, Gautham KS, Soll R. Sunlight for the prevention and treatment of hyperbilirubinemia in term and late preterm neonates. Cochrane Database Syst Rev. 2021;2021(7):CD013277. doi:10.1002/14651858.CD013277.pub2

Kemper AR, Newman TB, Slaughter JL, et al. Clinical Practice Guideline Revision: Management of Hyperbilirubinemia in the Newborn Infant 35 or More Weeks of Gestation. 2022;150(3).

Author
Donna M. D’Alessandro, MD
Professor of Pediatrics, University of Iowa