Biliary Atresia
Biliary Atresia Causes
Biliary atresia results when the bile ducts inside or outside the liver do not develop normally. It is unknown why the biliary system fails to develop normally. The bile ducts aid in removing waste from the liver and carry salts that help the small intestine break down fat. In babies with biliary atresia, bile flow from the liver to the gallbladder is hindered. This can cause liver damage and cirrhosis of the liver, which is deadly if not treated.
Biliary Atresia Definition
Biliary atresia is a rare condition found in newborn infants in which the common bile duct between the liver and the small intestine is blocked or missing. If it goes unrecognized, the condition leads to liver failure but not to kernicterus. This is due to the liver still able to conjugate bilirubin, and conjugated bilirubin is not able to cross the blood-brain barrier. The only effective treatments for biliary atresia are certain surgeries, or liver transplantation.
Biliary Atresia Prevalence
Biliary atresia is an extremely rare disorder. About one in 10,000 to 20,000 babies in the U.S are affected each year. Biliary atresia seems to affect females slightly more often than males. Within the same family, it is common for only one child in a pair of twins or only one child within the same family to acquire it. Asians and African-Americans are affected more often than Caucasians. There does not appear to be any correlation between medications or immunizations given immediately before or during pregnancy.
Biliary Atresia Symptoms and Signs
Initially, the symptoms cannot be distinguished from neonatal jaundice, a common phenomenon. Symptoms are usually displayed between two and six weeks after birth. Aside from jaundice, other symptoms include dark urine, pale stools, swollen abdominal region and large hardened liver (which may or may not be observable by the naked eye). Symptoms also include an enlarged spleen, foul-smelling stool, slow or no weight gain, and abnormally slow growth. Prolonged jaundice that is resistant to phototherapy or exchange transfusions should prompt an examination for secondary causes. By this time, liver enzymes are measured, and these tend to be grossly deranged. Hyperbilirubinaemia is joined together and therefore does not lead to kernicterus. Newborns with this condition may appear normal when they are born. However, jaundice (which is a yellow color to the skin, whites of the eyes, and mucous membranes) develops by the second or third week of life. The infant may gain weight normally during the first month, but then will lose it and become irritable. The infant's jaundice may also worsen.