Jaundice

Neonatal jaundice is a yellowing of the skin and other tissues of a newborn infant. A bilirubin level of more than 85 umol/l (5 mg/dL) manifests clinical jaundice in neonates whereas in adults 34 umol/l (2 mg/dL) would look icteric. In newborns jaundice is detected by blanching the skin with digital pressure so that it reveals underlying skin and subcutaneous tissue. Jaundice newborns have an apparent icteric sclera, and yellowing of the face, extending down onto the chest. This condition is common in upwards of 70% of newborns.

In neonates the dermal icterus is first noted in the face and as the bilirubin level rises proceeds caudal to the trunk and then to the extremities.^[1]

Notoriously inaccurate rules of thumb have been applied to the physical exam of the jaundiced infant. Some include estimation of serum bilirubin based on appearance. One such rule of thumb includes infants whose jaundice is restricted to the face and part of the trunk above the umbilicus, have the bilirubin less than 204 umol/l (12 mg/dL) (less dangerous level). Infants whose palms and soles are yellow, have serum bilirubin level over 255 umol/l (15 mg/dL) (more serious level).

Studies have shown that trained examiners assessment of levels of jaundice show moderate agreement with icterometer bilirubin measurements.^[1]

In infants jaundice can be measured using invasive or non-invasive methods. In non invasive method Ingram icterometer and Transcutaneous bilirubinometer are used.

From wikipedia