Congenital syphilis is caused by Treponema pallidum, which is acquired from a mother who was infected during pregnancy, or who had inadequately treated syphilis.

Congenital toxoplasmosis is caused by Toxoplasma gondii, which the fetus acquires when the mother has an acute infection. Fetal damage is most likely to occur if infection is acquired during the 2nd-6th month of gestation. 70% of infants are either…

Bilirubin encephalopathy is neurological damage that is caused by high levels of unconjugated bilirubin. Unconjugated bilirubin anion is unbound to albumin, enabling it to cross the blood-brain barrier, enter neurons, and disrupt energy metabolism, ultimately causing death. Definition of terms…

Phototherapy Phototherapy is a core treatment for neonatal jaundice. It works by converting unconjugated bilirubin into water-soluble isomers that can be excreted without conjugation by the liver. A wavelength of 460-490 nm (blue light) is the most effective. A higher…

Alagille syndrome is an autosomal dominant disorder of the liver, heart, and kidneys that results in bile duct paucity, which impairs the ability of hepatocytes to efficiently release conjugated bilirubin. It is caused by a JAG1 mutation. It can be…

Choledochal cysts are cystic lesions of the biliary tree. Its clinical and laboratory findings are similar to biliary atresia.

Biliary atresia is a progressive fibro-inflammatory obliteration of the lumen of the biliary tree. It causes conjugated hyperbilirubinaemia, since there are defects in the biliary tract, resulting in cholestasis. The conjugated bilirubin is reabsorbed into the bloodstream, causing a direct…

Neonatal hepatitis is inflammation of the liver that results in jaundice, poor growth, and an enlarged liver. It can be a congenital or an early-acquired infection. This infection leads to direct hyperbilirubinaemia. Organisms can be transmitted transplacentally, via cervical ascent,…

Dubin-Johnson syndrome is an autosomal recessive condition that is caused by a mutation of the MRP2 channel, which transports conjugated bilirubin into the bile canaliculi. It results in conjugated hyperbilirubinaemia. It is typically asymptomatic and usually presents in teenage years…

Criggler-Najjar syndrome is caused by a deficiency or absence of UDP-glucuronosyltransferase (UGT1A1), which leads to unconjugated hyperbilirubinaemia. Types of Criggler-Najjar Syndrome Type Description Criggler-Najjar Type I Absence of UGT1A1, resulting in inability to conjugate bilirubin (Indirect hyperbilirubinemia). It does not…