Neonatal Jaundice Jaundice occurring in the newborn is referred to as neonatal jaundice. It is quite common, usually harmless and resolves in two weeks ( physiological jaundice ). If it is severe and prolonged, it may be pathological, requiring further investigations to find the cause. It is characterised by yellowish discolor ation of the skin and eyes due to accumulation of a toxic pigment called bilirubin in the blood. Jaundice per se is not a disease but a symptom that may signify an underlying disease. Approximately 60% of term babies and 80% of preterm babies develop jaundice. Bilirubin Formation and Excretion One of the important sources of bilirubin in the body is when red cells are broken down due to aging of the cells when they are replaced by new red cells from the bone marrow. The bilirubin from red cell breakdown is processed in the liver and excreted from the body . Physiological Jaundice • The most common cause of neonatal jaundice is physiological jaundice. • This occurs because newborns have more red cells than adults and hence more is broken down . • Additionally the newborn liver is immature and unable to handle the increased amounts of bilirubin being formed. • This results in accumulation of bilirubin in the blood with symptoms of jaundice. The physiological jaundice described above usually presents between day 2 – 4 after birth, peaks at one week and gradually resolves spontaneously in about two weeks . Pathological Jaundice In some cases however, jaundice is caused due to some serious underlying disease of the blood or liver. This is termed pathological jaundice. Pathological jaundice shows many of the following features • It appears on the first day of life itself • Bilirubin levels in the blood may be very high with severe jaundice • Baby is ill and does not feed well and appears irritable • Jaundice is still present even after two weeks (prolonged jaundice); the baby passes pale chalky appearing stools (due to absence of bilirubin in the stool) and dark colored urine (due to increased bilirubin pigment) • Enlarged liver and spleen, small head size (microcephaly) seen in some congenital infections It is important to recognise and treat pathological jaundice in the neonate promptly because high bilirubin levels in the bloodstream (hyperbilirubinemia) can result in deposition of bilurubin in the brain with serious consequences . Causes of Pathological Jaundice • ABO or Rh incompatibility between mother’s and baby’s blood group - (Increased Red cell destruction) • Inherited disorders of the red cell - (Increased Red cell break down) • Neonatal infections – Toxoplasmosis, rubella, cytomegalovirus (CMV), herpes simplex, syphilis. These are referred to as TORCHS complex and should be ruled out • Inherited disorders of bilirubin metabolism – Criggler Najjar syndrome, Dubin Johnson syndrome, Gilbert syndrome • Other uncommon causes include diseases of the biliary system eg biliary atresia and certain inherited metabolic diseases