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Cholestasis is a condition where bile cannot flow from the liver to the duodenum. The two basic distinctions are an obstructive type of cholestasis where there is a mechanical blockage in the duct system that can occur from a gallstone or malignancy, and metabolic types of cholestasis which are disturbances in bile formation that can occur because of genetic defects or acquired as a side effect of many medications.
The onset of the disease is usually before age 2, but patients have been diagnosed with PFIC even into adolescence. Of the three entities, PFIC-3 usually presents earliest. Patients usually present in early childhood with cholestasis, jaundice, and failure to thrive. Intense pruritus is characteristic; in patients who present in adolescence, it has been linked with suicide. Patients may have fat malabsorption, leading to fat soluble vitamin deficiency, and complications, including osteopenia.
Possible causes:
- pregnancy
- androgens
- birth control pills
- antibiotics (such as TMP/SMX)
- abdominal mass (e.g. cancer)
- biliary atresia and other pediatric liver diseases
- biliary trauma
- congenital anomalies of the biliary tract
- gallstones
- acute hepatitis
- cystic fibrosis
- intrahepatic cholestasis of pregnancy (obstetric cholestasis)
- primary biliary cirrhosis, an autoimmune disorder
- primary sclerosing cholangitis, associated with inflammatory bowel disease
- some drugs (e.g. flucloxacillin and erythromycin)
Drugs such as gold salts, nitrofurantoin, anabolic steroids, chlorpromazine, prochlorperazine, sulindac, cimetidine, erythromycin, estrogen, and statins can cause cholestasis and may result in damage to the liver.
Initially, the symptoms of biliary atresia are indistinguishable from those of neonatal jaundice, a usually harmless condition commonly seen in infants. Distinctive symptoms of biliary atresia are usually evident between one and six weeks after birth. Infants and children with biliary atresia develop progressive cholestasis, a condition in which bile is unable to leave the liver and builds up inside of it. When the liver is unable to excrete bilirubin through the bile ducts in the form of bile, bilirubin begins to accumulate in the blood, causing symptoms. These symptoms include yellowing of the skin, itchiness, poor absorption of nutrients (causing delays in growth), pale stools, dark urine, and a swollen abdomen. Eventually, cirrhosis with portal hypertension will develop. If left untreated, biliary atresia can lead to liver failure. Unlike other forms of jaundice, however, biliary-atresia-related cholestasis mostly does not result in kernicterus, a form of brain damage resulting from liver dysfunction. This is because in biliary atresia, the liver, although diseased, is still able to conjugate bilirubin, and conjugated bilirubin is unable to cross the blood–brain barrier.
People with PBC experience fatigue (80%) that leads to sleepiness during the daytime; more than half of those have severe fatigue. Itching (pruritus) occurs in 20–70%. People with more severe PBC may have jaundice (yellowing of the eyes and skin). PBC impairs bone density and there is an increased risk of fracture. Xanthelasma (skin lesions around the eyes) or other xanthoma may be present as a result of increased cholesterol levels.
PBC can eventually progress to cirrhosis of the liver. This in turn may lead to a number of symptoms or complications:
- Fluid retention in the abdomen (ascites) in more advanced disease
- Enlarged spleen in more advanced disease
- Oesophageal varices in more advanced disease
- Hepatic encephalopathy, including coma in extreme cases in more advanced disease.
People with PBC may also sometimes have the findings of an associated extrahepatic autoimmune disorder such as rheumatoid arthritis or Sjögren's syndrome (in up to 80% of cases).
Cholestasis means "the slowing or stopping of bile flow" which can be caused by any number of diseases of the liver (which produces the bile), the gallbladder (which stores the bile), or biliary tract (also known as the biliary tree, the conduit that allows the bile to leave the liver and gallbladder and enter the small intestine). When this occurs, conjugated bilirubin and the waste products that usually would be cleared in bile reflux back into the bloodstream. This causes a primarily conjugated hyperbilirubinemia and jaundice; the liver conjugates the bile to make it water-soluble and because the bile has already been processed by the liver, when it gets backed up because of a blockage and is refluxed into the blood, the blood will have high levels of conjugated bilirubin. This is in contrast to primarily unconjugated hyperbilirubinemia which is the water-insoluble form that is bound to serum albumin; the liver has not had a chance to conjugate the bilirubin yet and can be caused either because too much unconjugated bilirubin is made (such as in massive hemolysis or ineffective erythropoiesis) or because too little is conjugated (Gilbert's disease or Crigler-Najjar syndrome). Unconjugated hyperbilirubinemia does not typically cause pruritus.
It is thought that bile salts that deposit into the skin are responsible for the pruritus (itching) but the levels of bilirubin in the bloodstream and the severity of the pruritus does not appear to be highly correlated. Patients that have been administered bile salt chelating agents do report some relief, however, and patients that have complete liver cell failure (and therefore cannot make these products to begin with) do not have pruritus. This suggests that products made by the liver must have some role in pruritus although it is not known exactly which product is responsible.
Neonatal cholestasis defines persisting conjugated hyperbilirubinemia in the newborn with conjugated bilirubin levels exceeding 15% (5.0 mg/dL) of total bilirubin level. The disease is either due to defects in bile excretion from hepatocytes or impaired bile flow.
General presentations in neonates include abdominal pain and general GI upset. Physical examination may show palpable liver and enlarged spleen. Differential diagnosis typically presents with a host of possibilities, many of them not treatable. Histopathology shows dilated bile duct system at all levels and bile duct proliferation in response to back pressure. The incidence has been found to be about 1:2,500 live births.
Cholestatic pruritus is the sensation of itch due to nearly any liver disease, but the most commonly associated entities are primary biliary cirrhosis, primary sclerosing cholangitis, obstructive choledocholithiasis, carcinoma of the bile duct, cholestasis (also see drug-induced pruritus), and chronic hepatitis C viral infection and other forms of viral hepatitis.
Primary sclerosing cholangitis is typically classified into three subgroups based on whether the small and/or large bile ducts are affected. The subgroups of PSC include the following:
- Classic PSC
- Small-duct PSC
- PSC associated with autoimmune hepatitis
Types of progressive familial intrahepatic cholestasis are as follows:
- Type 1 (OMIM #211600), also called Byler disease
- Type 2 (OMIM #601847)
- Type 3 (OMIM #602347), also called ABCB4 deficiency or MDR3 deficiency
- Type 4 (OMIM #615878), from mutation in "TJP2"
Primary biliary cholangitis (PBC), also known as primary biliary cirrhosis, is an autoimmune disease of the liver. It results from a slow, progressive destruction of the small bile ducts of the liver, causing bile and other toxins to build up in the liver, a condition called cholestasis. Further slow damage to the liver tissue can lead to scarring, fibrosis, and eventually cirrhosis.
Common symptoms are tiredness, itching and, in more advanced cases, jaundice. In early cases, there may only be changes in blood tests.
PBC is a relatively rare disease, affecting up to 1 in 3–4,000 people. It is much more common in women, with a sex ratio of at least 9:1 female to male.
The condition has been recognised since at least 1851 and was named "primary biliary cirrhosis" in 1949. Because cirrhosis is a feature only of advanced disease, a change of its name to "primary biliary cholangitis" was proposed by patient advocacy groups in 2014.
Nearly half of people with PSC do not have symptoms and are often incidentally discovered to have PSC due to abnormal liver function tests, but a substantial proportion will have debilitating signs and symptoms of the disease. Signs and symptoms of PSC may include severe itching and non-specific fatigue. Yellowing of the skin and white portion of the eyes may also be seen. Enlargement of the liver and spleen are seen in approximately 40% of affected individuals. Abdominal pain affects about 20% of people with PSC.
Multiple episodes of life-threatening acute cholangitis (infection within the bile ducts) can be seen due to impaired drainage of the bile ducts, which increases the risk of infection.
- Dark urine due to excess conjugated bilirubin, which is water-soluble and excreted by the kidneys (i.e. choluria)
- Malabsorption, especially of fat, and steatorrhea (fatty stool), due to an inadequate amount of bile reaching the small intestine, leading to decreased levels of the fat-soluble vitamins, A, D, E and K.
- Portal hypertension, a complication of cirrhosis, which can manifest with esophageal and parastomal varices as well as hepatic encephalopathy (mental status alteration/disturbance caused by liver dysfunction and shunting of blood away from the scarred liver; such that ammonia detoxification is reduced with concomitant encephalopathy).
Biliary atresia, also known as extrahepatic ductopenia and progressive obliterative cholangiopathy, is a childhood disease of the liver in which one or more bile ducts are abnormally narrow, blocked, or absent. It can be congenital or acquired. As a birth defect in newborn infants, it has an incidence of one in 10,000–15,000 live births in the United States, and a prevalence of one in 16,700 in the British Isles. Biliary atresia is most common in East Asia, with a frequency of one in 5,000.
The causes of biliary atresia are not well understood. Congenital biliary atresia has been associated with certain genes, while acquired biliary atresia is thought to be a result of an autoimmune inflammatory response, possibly due to a viral infection of the liver soon after birth. The only effective treatments are surgeries such as the Kasai procedure and liver transplantation.
There are more than a hundred different kinds of liver disease. Symptoms may include jaundice and weight loss. These are some of the most common:
- Fascioliasis, a parasitic infection of liver caused by a Liver fluke of the "Fasciola" genus, mostly the "Fasciola hepatica".
- Hepatitis, inflammation of the liver, is caused by various viruses (viral hepatitis) also by some liver toxins (e.g. alcoholic hepatitis), autoimmunity (autoimmune hepatitis) or hereditary conditions.
- Alcoholic liver disease is a hepatic manifestation of alcohol overconsumption, including fatty liver disease, alcoholic hepatitis, and cirrhosis. Analogous terms such as "drug-induced" or "toxic" liver disease are also used to refer to disorders caused by various drugs.
- Fatty liver disease (hepatic steatosis) is a reversible condition where large vacuoles of triglyceride fat accumulate in liver cells. Non-alcoholic fatty liver disease is a spectrum of disease associated with obesity and metabolic syndrome.
- Hereditary diseases that cause damage to the liver include hemochromatosis, involving accumulation of iron in the body, and Wilson's disease. Liver damage is also a clinical feature of alpha 1-antitrypsin deficiency and glycogen storage disease type II.
- In transthyretin-related hereditary amyloidosis, the liver produces a mutated transthyretin protein which has severe neurodegenerative and/or cardiopathic effects. Liver transplantation can give a curative treatment option.
- Gilbert's syndrome, a genetic disorder of bilirubin metabolism found in a small percent of the population, can cause mild jaundice.
- Cirrhosis is the formation of fibrous tissue (fibrosis) in the place of liver cells that have died due to a variety of causes, including viral hepatitis, alcohol overconsumption, and other forms of liver toxicity. Cirrhosis causes chronic liver failure.
- Primary liver cancer most commonly manifests as hepatocellular carcinoma and/or cholangiocarcinoma; rarer forms include angiosarcoma and hemangiosarcoma of the liver. (Many liver malignancies are secondary lesions that have metastasized from primary cancers in the gastrointestinal tract and other organs, such as the kidneys, lungs.)
- Primary biliary cirrhosis is a serious autoimmune disease of the bile capillaries.
- Primary sclerosing cholangitis is a serious chronic inflammatory disease of the bile duct, which is believed to be autoimmune in origin.
- Budd–Chiari syndrome is the clinical picture caused by occlusion of the hepatic vein.
Liver disease (also called hepatic disease) is a type of damage to or disease of the liver.
The main sign of jaundice is a yellowish discoloration of the white area of the eye and the skin. Urine is dark in colour.
Slight increases in serum bilirubin are best detected by examining the sclerae, which have a particular affinity for bilirubin due to their high elastin content. The presence of scleral icterus indicates a serum bilirubin of at least 3 mg/dL.
The conjunctiva of the eye are one of the first tissues to change color as bilirubin levels rise in jaundice. This is sometimes referred to as "scleral icterus". However, the sclera themselves are not "icteric" (stained with bile pigment) but rather the conjunctival membranes that overlie them. The yellowing of the "white of the eye" is thus more properly termed "conjunctival icterus". The term "icterus" itself is sometimes incorrectly used to refer to jaundice that is noted in the sclera of the eyes; however, its more common and more correct meaning is entirely synonymous with jaundice.
People with neonatal hepatitis caused by rubella or cytomegalovirus are at risk of developing an infection of the brain that could lead to mental retardation or cerebral palsy. Many of these infants will also have permanent liver disease from the destruction of liver cells and the resulting scarring (cirrhosis).
Infants with giant cell hepatitis usually recover (80 percent of cases) with little or no scarring to their liver. Their growth pattern resumes as bile flows normally into the small intestine for digestion and to absorb vitamins.
About 20 percent of the infants with neonatal giant cell hepatitis develop chronic liver disease and cirrhosis. Their liver becomes very hard, due to the scarring, and the jaundice does not disappear by six months of age. Infants who reach this point in the disease eventually will require a liver transplant.
Because of the blockage of the bile ducts and the damage caused to liver cells, infants with chronic neonatal hepatitis will not be able to digest fats and will not be able to absorb vitamins A, D, E and K. The lack of vitamin D leads to poor bone and cartilage development (rickets). Vitamin A is also needed for normal growth and good vision. Vitamin K deficiency is associated with easy bruising and a tendency to bleed, whereas the lack of vitamin E results in poor coordination.
Chronic neonatal hepatitis will lead to the inability of the liver to eliminate toxins in the bile. This causes itching, skin eruptions and irritability.
Hyperbilirubinemia, more precisely hyperbilirubinemia due to the unconjugated fraction, may cause bilirubin to accumulate in the gray matter of the central nervous system, potentially causing irreversible neurological damage leading to a condition known as kernicterus. Depending on the level of exposure, the effects range from clinically unnoticeable to severe brain damage and even death. Newborns are especially vulnerable to hyperbilirubinemia-induced neurological damage and therefore must be carefully monitored for alterations in their serum bilirubin levels.
Neonatal hepatitis is a form of hepatitis that affects the fetuses and neonates.
Presentation can be atypical with no pain or fever especially in the elderly population. Hepatolithiasis may present with biliary colic, acute pancreatitis, obstructive jaundice and less commonly, hepatomegaly and abnormal liver chemistry. Chronic biliary obstruction may cause jaundice, pruritus, liver abscess, and liver atrophy, mostly affecting the left lobe and the left lateral segment of the liver, and eventually secondary biliary cirrhosis and cholangiocarcinoma.
The first symptoms typically include fever, intermittent abdominal pain, and hepatomegaly. Occasionally, jaundice occurs.
Morbidity is common and is caused by complications of cholangitis, sepsis, choledocholithiasis, and cholangiocarcinoma. These morbid conditions often prompt the diagnosis. Portal hypertension may be present, resulting in other conditions including splenomegaly, hematemesis, and melena. These problems can severely affect the patient's quality of life. In a 10-year period between 1995 and 2005, only 10 patients were surgically treated for Caroli disease, with an average patient age of 45.8 years.
After reviewing 46 cases of Caroli disease before 1990, 21.7% of the cases were the result of an intraheptic cyst or nonobstructive biliary tree dilation, 34.7% were linked with congenital hepatic fibrosis, 13% were isolated choledochal cystic dilation, and the remaining 24.6% had a combination of all three.
Suppurative cholangitis, liver abscess, empyema of the gallbladder, acute pancreatitis, thrombophlebitis of hepatic or portal veins, and septicemia are acute complications of the disease, to which patients may succumb during the acute attacks.
Chronically, complications include cholangiocarcinoma and intraductal papillary neoplasm.
Ductopenia refers to a reduction in the number of ducts in an organ. It is the histological hallmark of vanishing bile duct syndrome (typically <0.5 bile ducts per portal triad). The most common cause of ductopenia is primary biliary cholangitis.
Other causes of ductopenia include failing liver transplant, Hodgkin's lymphoma, graft-versus-host disease (GVHD), sarcoid, Cytomegalovirus infection, HIV and medication toxicity.
A person with cholangitis may complain of abdominal pain (particularly in the right upper quadrant of the abdomen), fever, rigors (uncontrollable shaking) and a feeling of uneasiness (malaise). Some may report jaundice (yellow discoloration of the skin and the whites of the eyes).
Physical examination findings typically include jaundice and right upper quadrant tenderness. Charcot's triad is a set of three common findings in cholangitis: abdominal pain, jaundice, and fever. This was assumed in the past to be present in 50–70% of cases, although more recently the frequency has been reported as 15–20%. Reynolds' pentad includes the findings of Charcot's triad with the presence of septic shock and mental confusion. This combination of symptoms indicates worsening of the condition and the development of sepsis, and is seen less commonly still.
In the elderly, the presentation may be atypical; they may directly collapse due to sepsis without first showing typical features. Those with an indwelling stent in the bile duct (see below) may not develop jaundice.
Murphy's sign is commonly negative on physical examination in choledocholithiasis, helping to distinguish it from cholecystitis. Jaundice of the skin or eyes is an important physical finding in biliary obstruction. Jaundice and/or clay-colored stool may raise suspicion of choledocholithiasis or even gallstone pancreatitis. If the above symptoms coincide with fever and chills, the diagnosis of ascending cholangitis may also be considered.
Greater than 70% of people with gallstones are asymptomatic and are found incidentally on ultrasound. Studies have shown that 10% of those people will develop symptoms within five years of diagnosis and 20% within 20 years.