Hyperbilirubinemia type 2

From WikiMD's Food, Medicine & Wellness Encyclopedia

Hyperbilirubinemia Type 2, also known as Crigler-Najjar syndrome type II or Arias syndrome, is a rare genetic disorder characterized by the body's inability to properly process bilirubin. Bilirubin is a yellow compound that occurs in the normal catabolic pathway that breaks down heme in red blood cells. The condition leads to an excessive buildup of bilirubin in the blood, a condition known as hyperbilirubinemia. Unlike Hyperbilirubinemia Type 1, which is more severe and often requires a liver transplant, Type 2 can be managed with certain treatments.

Causes[edit | edit source]

Hyperbilirubinemia Type 2 is caused by mutations in the UGT1A1 gene, which encodes the enzyme UDP-glucuronosyltransferase 1-1. This enzyme is crucial for the conversion of bilirubin into a form that can be eliminated from the body through bile. A deficiency in UDP-glucuronosyltransferase 1-1 activity leads to the accumulation of unconjugated bilirubin in the blood.

Symptoms[edit | edit source]

The primary symptom of Hyperbilirubinemia Type 2 is jaundice, which is a yellowing of the skin and whites of the eyes. This symptom is due to the high levels of bilirubin in the blood. Other symptoms may include fatigue, abdominal pain, and a yellow tinge to the urine or stool. If left untreated, high levels of bilirubin can lead to bilirubin encephalopathy, a condition that can cause permanent brain damage.

Diagnosis[edit | edit source]

Diagnosis of Hyperbilirubinemia Type 2 involves a series of tests, including blood tests to measure the levels of bilirubin. Genetic testing may also be conducted to identify mutations in the UGT1A1 gene. Liver function tests are often performed to rule out other causes of jaundice.

Treatment[edit | edit source]

Treatment for Hyperbilirubinemia Type 2 typically involves the use of phenobarbital, which can help to lower bilirubin levels by increasing the activity of UDP-glucuronosyltransferase. In some cases, phototherapy may be used to treat newborns with jaundice. Unlike Type 1, liver transplantation is not usually required for Type 2.

Prognosis[edit | edit source]

With proper management, individuals with Hyperbilirubinemia Type 2 can lead normal, healthy lives. It is important for those with the condition to regularly monitor their bilirubin levels and adhere to their treatment plan.

Hyperbilirubinemia type 2 Resources
Doctor showing form.jpg
Wiki.png

Navigation: Wellness - Encyclopedia - Health topics - Disease Index‏‎ - Drugs - World Directory - Gray's Anatomy - Keto diet - Recipes

Search WikiMD


Ad.Tired of being Overweight? Try W8MD's physician weight loss program.
Semaglutide (Ozempic / Wegovy and Tirzepatide (Mounjaro / Zepbound) available.
Advertise on WikiMD

WikiMD is not a substitute for professional medical advice. See full disclaimer.

Credits:Most images are courtesy of Wikimedia commons, and templates Wikipedia, licensed under CC BY SA or similar.

Contributors: Prab R. Tumpati, MD