In normal conditions, bile flows from the hepatocytes (liver cells) to the bile ducts, bile salts are stored at the gallbladder. After a meal, the gallbladder expulses the bile salts to the small bowel. These substances help digest the fat contents of the food. Cholestasis is defined as a reduction in bile flow that could be due to impaired secretion by hepatocytes or to obstruction in bile flow at the level of either the intra-hepatic or extra-hepatic bile ducts. Therefore, the clinical definition of cholestasis is any condition in which bile salts normally excreted into bile are retained. The serum concentrations of conjugated bilirubin and bile salts are the most commonly measured.

Bile acid synthesis disorders (BASDs) are a group of rare metabolic disorders characterized by defects in the creation (synthesis) of bile acids. Bile acids are chemical compounds found in the liver that have several roles in the body including promoting the flow and excretion of bile and assisting in the intestinal absorption of fat and fat-soluble vitamins. Bile acids are formed from cholesterol and, therefore, bile acid synthesis serves as the main pathway in breaking down and eliminating cholesterol from the body (cholesterol degradation). The failure to produce normal or functional bile acids results in the accumulation of abnormal bile acids and other substances that normal would be broken down (intermediary metabolites) within the body. The resulting accumulation of abnormal bile acids, intermediary metabolites and cholesterol in the body can damage certain organ systems. The main symptom of most (but not all) BASDs is interruption or suppression of the flow of bile from the liver (cholestasis) and fat-soluble vitamin malabsorption. Additional symptoms such as progressive neurological disease may develop in certain cases and can occur in the absence of liver disease. In many cases, symptoms or signs are present at birth or during the newborn period. If untreated, the more severe forms of these disorders can eventually progress to cause life-threatening complications such as scarring of the liver (cirrhosis) and liver failure. Many of these disorders can be successfully treated by replacing the missing bile acids (bile acid replacement therapy).

Wilson's disease is a rare inherited disorder that causes copper accumulation in the liver, brain and other vital organs. Symptoms typically begin between 5 and 35 years of age. Copper plays a key role in the development of healthy nerves, bones, collagen and the skin pigment melanin. Normally, copper is absorbed from your food, and any excess is excreted through bile — a substance produced in your liver. But in people with Wilson's disease, copper isn't eliminated properly and instead accumulates, possibly to a life-threatening level. When diagnosed early, Wilson's disease is treatable, and many people with the disorder live normal lives.

Congenital sucrase-isomaltase deficiency: is a disorder that affects a person's ability to digest certain sugars. People with this condition cannot break down the sugars sucrose and maltose. Sucrose and maltose, two-disaccharides, are broken down into simple sugars during digestion. Sucrose is broken down into glucose and another simple sugar called fructose, and maltose is broken down into two glucose molecules. People with congenital sucrase-isomaltase deficiency cannot break down the sugars sucrose and maltose, and other compounds made from these sugar molecules (carbohydrates). Although some patients can tolerate low sugar diets, most of the patients required enzyme replacement therapy. Sucraid is the first and only pharmaceutical drug therapy approved by the FDA as a simple, safe and effective enzyme replacement therapy of the genetically determined sucrase deficiency that is part of congenital sucrase-isomaltase deficiency.