Disorders in the complex internal organ in the upper right abdomen, which has hundreds of functions, mainly to produce key proteins and other chemicals, to regulate the chemistry of the blood, to store the sugar glucose as glycogen until needed, and to clear drugs, poisons, and other unwanted substances from the blood, excreting these waste products in bile. Children may experience various kinds of problems with the liver. Inherited abnormalities may cause the liver to malfunction, as in alpha 1-antitrypsin deficiency, galactosemia, glycogen storage diseases, and Wilson’s disease. Infections, structural problems, or other disorders may cause hepatitis, inflammation of the liver, or cholangitis, inflammation of the bile duct. Ailments of even more complicated or obscure origin may also affect the liver, including biliary atresia and Reye’s syndrome.