Cirrhosis is a consequence of chronic liver disease characterized by replacement of liver tissue by fibrosis, scar tissue and regenerative nodules (lumps that occur as a result of a process in which damaged tissue is regenerated), leading to loss of liver function. Cirrhosis is most commonly caused by alcoholism, hepatitis B and C, and fatty liver disease, but has many other possible causes. Some cases are idiopathic, i.e., of unknown cause.
Ascites (fluid retention in the abdominal cavity) is the most common complication of cirrhosis, and is associated with a poor quality of life, increased risk of infection, and a poor long-term outcome. Other potentially life-threatening complications are hepatic encephalopathy (confusion and coma) and bleeding from esophageal varices. Cirrhosis is generally irreversible, and treatment usually focuses on preventing progression and complications. In advanced stages of cirrhosis the only option is a liver transplant.
The word "cirrhosis" derives from Greek κιρρός meaning yellowish, tawny (the orange-yellow colour of the diseased liver) + Eng. med. suff. -osis. While the clinical entity was known before, it was René Laennec who gave it the name "cirrhosis" in his 1819 work in which he also describes the stethoscope.
Some of the following signs and symptoms may occur in the presence of cirrhosis or as a result of the complications of cirrhosis. Many are nonspecific and may occur in other diseases and do not necessarily point to cirrhosis. Likewise, the absence of any does not rule out the possibility of cirrhosis.
* Spider angiomata or spider nevi. Vascular lesions consisting of a central arteriole surrounded by many smaller vessels because of an increase in estradiol. These occur in about 1/3 of cases.
* Palmar erythema. Exaggerations of normal speckled mottling of the palm, because of altered sex hormone metabolism.
* Nail changes.
* Muehrcke's lines - paired horizontal bands separated by normal color resulting from hypoalbuminemia (inadequate production of albumin).
* Terry's nails - proximal two-thirds of the nail plate appears white with distal one-third red, also due to hypoalbuminemia
* Clubbing - angle between the nail plate and proximal nail fold > 180 degrees
# Hypertrophic osteoarthropathy. Chronic proliferative periostitis of the long bones that can cause considerable pain.
# Dupuytren's contracture. Thickening and shortening of palmar fascia that leads to flexion deformities of the fingers. Thought to be caused by fibroblastic proliferation and disorderly collagen deposition. It is relatively common (33% of patients).
# Gynecomastia. Benign proliferation of glandular tissue of male breasts presenting with a rubbery or firm mass extending concentrically from the nipples. This is caused by increased estradiol and can occur in up to 66% of patients.
# Hypogonadism. Manifested as impotence, infertility, loss of sexual drive, and testicular atrophy because of primary gonadal injury or suppression of hypothalamic or pituitary function.
# Liver size. Can be enlarged, normal, or shrunken.
# Splenomegaly (increase in size of the spleen). Caused by congestion of the red pulp as a result of portal hypertension.
# Ascites. Accumulation of fluid in the peritoneal cavity giving rise to flank dullness (needs about 1500 mL to detect flank dullness).
# Caput medusa. In portal hypertension, the umbilical vein may open. Blood from the portal venous system may be shunted through the periumbilical veins into the umbilical vein and ultimately to the abdominal wall veins, manifesting as caput medusa.
# Cruveilhier-Baumgarten murmur. Venous hum heard in epigastric region (on examination by stethoscope) because of collateral connections between portal system and the remnant of the umbilical vein in portal hypertension.
# Fetor hepaticus. Musty odor in breath as a result of increased dimethyl sulfide.
# Jaundice. Yellow discoloring of the skin, eye, and mucus membranes because of increased bilirubin (at least 2–3 mg/dL or 30 mmol/L). Urine may also appear dark.
# Asterixis. Bilateral asynchronous flapping of outstretched, dorsiflexed hands seen in patients with hepatic encephalopathy.
# Other. Weakness, fatigue, anorexia, weight loss.
As the disease progresses, complications may develop. In some people, these may be the first signs of the disease.
* Bruising and bleeding resulting from decreased production of coagulation factors.
* Jaundice as a result of decreased processing of bilirubin.
* Itching (pruritus) because of bile salt products deposited in the skin.
* Hepatic encephalopathy - the liver does not clear ammonia and related nitrogenous substances from the blood, which are carried to the brain, affecting cerebral functioning: neglect of personal appearance, unresponsiveness, forgetfulness, trouble concentrating, or changes in sleep habits.
* Sensitivity to medication caused by decreased metabolism of the active compounds.
* Hepatocellular carcinoma is primary liver cancer, a frequent complication of cirrhosis. It has a high mortality rate.
* Portal hypertension - blood normally carried from the intestines and spleen through the hepatic portal vein flows more slowly and the pressure increases; this leads to the following complications:
o Ascites - fluid leaks through the vasculature into the abdominal cavity.
o Esophageal varices - collateral portal blood flow through vessels in the stomach and esophagus. These blood vessels may become enlarged and are more likely to burst.
* Problems in other organs.
o Cirrhosis can cause immune system dysfunction, leading to infection. Signs and symptoms of infection may be aspecific are more difficult to recognize (e.g., worsening encephalopathy but no fever).
o Fluid in the abdomen (ascites) may become infected with bacteria normally present in the intestines (spontaneous bacterial peritonitis).
o Hepatorenal syndrome - insufficient blood supply to the kidneys, causing acute renal failure. This complication has a very high mortality (over 50%).
o Hepatopulmonary syndrome - blood bypassing the normal lung circulation (shunting), leading to cyanosis and dyspnea (shortness of breath), characteristically worse on sitting up.
o Portopulmonary hypertension - increased blood pressure over the lungs as a consequence of portal hypertension.
o Portal hypertensive gastropathy which refers to changes in the mucosa of the stomach in patients with portal hypertension, and is associated with cirrhosis severity.
Cirrhosis has many possible causes; sometimes more than one cause is present in the same patient. In the Western World, chronic alcoholism and hepatitis C are the most common causes.
* Alcoholic liver disease (ALD). Alcoholic cirrhosis develops for between 10% and 20% of individuals who drink heavily for a decade or more. Alcohol seems to injure the liver by blocking the normal metabolism of protein, fats, and carbohydrates. Patients may also have concurrent alcoholic hepatitis with fever, hepatomegaly, jaundice, and anorexia. AST and ALT are both elevated but less than 300 IU/L with a AST:ALT ratio > 2.0, a value rarely seen in other liver diseases. Liver biopsy may show hepatocyte necrosis, Mallory bodies, neutrophilic infiltration with perivenular inflammation.
* Non-alcoholic steatohepatitis (NASH). In NASH, fat builds up in the liver and eventually causes scar tissue. This type of hepatitis appears to be associated with diabetes, protein malnutrition, obesity, coronary artery disease, and treatment with corticosteroid medications. This disorder is similar to that of alcoholic liver disease but patient does not have an alcohol history. Biopsy is needed for diagnosis.
* Chronic hepatitis C. Infection with the hepatitis C virus causes inflammation of the liver and a variable grade of damage to the organ that over several decades can lead to cirrhosis. Cirrhosis caused by hepatitis C is the most common reason for liver transplant. Can be diagnosed with serologic assays that detect hepatitis C antibody or viral RNA. The enzyme immunoassay, EIA-2, is the most commonly used screening test in the US.
* Chronic hepatitis B. The hepatitis B virus causes liver inflammation and injury that over several decades can lead to cirrhosis. Hepatitis D is dependent on the presence of hepatitis B and accelerates cirrhosis in co-infection. Chronic hepatitis B can be diagnosed with detection of HBsAG > 6 months after initial infection. HBeAG and HBV DNA are determined to assess whether patient will need antiviral therapy.
* Primary biliary cirrhosis. May be asymptomatic or complain of fatigue, pruritus, and non-jaundice skin hyperpigmentation with hepatomegaly. There is prominent alkaline phosphatase elevation as well as elevations in cholesterol and bilirubin. Gold standard diagnosis is antimitochondrial antibodies with liver biopsy as confirmation if showing florid bile duct lesions. It is more common in women.
* Primary sclerosing cholangitis. PSC is a progressive cholestatic disorder presenting with pruritus, steatorrhea, fat soluble vitamin deficiencies, and metabolic bone disease. There is a strong association with inflammatory bowel disease (IBD), especially ulcerative colitis. Diagnosis is best with contrast cholangiography showing diffuse, multifocal strictures and focal dilation of bile ducts, leading to a beaded appearance. Non-specific serum immunoglobulins may also be elevated.
* Autoimmune hepatitis. This disease is caused by the immunologic damage to the liver causing inflammation and eventually scarring and cirrhosis. Findings include elevations in serum globulins, especially gamma globulins. Therapy with prednisone and/or azathioprine is beneficial. Cirrhosis due to autoimmune hepatitis still has 10-year survival of 90%+. There is no specific tool to diagnose autoimmune but it can be beneficial to initiate a trial of corticosteroids.
* Hereditary hemochromatosis. Usually presents with family history of cirrhosis, skin hyperpigmentation, diabetes mellitus, pseudogout, and/or cardiomyopathy, all due to signs of iron overload. Labs will show fasting transferrin saturation of > 60% and ferritin > 300 ng/mL. Genetic testing may be used to identify HFE mutations. If these are present, biopsy may not need to be performed. Treatment is with phlebotomy to lower total body iron levels.
* Wilson's disease. Autosomal recessive disorder characterized by low serum ceruloplasmin and increased hepatic copper content on liver biopsy. May also have Kayser-Fleischer rings in the cornea and altered mental status.
* Alpha 1-antitrypsin deficiency (AAT). Autosomal recessive disorder. Patients may also have COPD, especially if they have a history of tobacco smoking. Serum AAT levels are low. Recombinant AAT is used to prevent lung disease due to AAT deficiency.
* Cardiac cirrhosis. Due to chronic right sided heart failure which leads to liver congestion.
* Galactosemia
* Glycogen storage disease type IV
* Cystic fibrosis
* Hepatotoxic drugs or toxins
* Certain parasitic infections (such as schistosomiasis)
* Lysosomal acid lipase deficiency (LAL Deficiency) is a rare autosomal recessive genetic condition and is characterized by hepatomegaly, persistently abnormal LFTs and type II hyperlipidemia. Splenomegaly and evidence of mild hypersplenism may affect some patients. Untreated, LAL Deficiency may lead to fibrosis, cirrhosis, liver failure and death.
The liver plays a vital role in synthesis of proteins (e.g., albumin, clotting factors and complement), detoxification and storage (e.g., vitamin A). In addition, it participates in the metabolism of lipids and carbohydrates.
Cirrhosis is often preceded by hepatitis and fatty liver (steatosis), independent of the cause. If the cause is removed at this stage, the changes are still fully reversible.
The pathological hallmark of cirrhosis is the development of scar tissue that replaces normal parenchyma, blocking the portal flow of blood through the organ and disturbing normal function. Recent research shows the pivotal role of the stellate cell, a cell type that normally stores vitamin A, in the development of cirrhosis. Damage to the hepatic parenchyma leads to activation of the stellate cell, which becomes contractile (called myofibroblast) and obstructs blood flow in the circulation. In addition, it secretes TGF-β1, which leads to a fibrotic response and proliferation of connective tissue. Furthermore, it secretes TIMP 1 and 2, naturally occurring inhibitors of matrix metalloproteinases, which prevents them from breaking down fibrotic material in the extracellular matrix.
The fibrous tissue bands (septa) separate hepatocyte nodules, which eventually replace the entire liver architecture, leading to decreased blood flow throughout. The spleen becomes congested, which leads to hypersplenism and increased sequestration of platelets. Portal hypertension is responsible for most severe complications of cirrhosis.
The following findings are typical in cirrhosis:
* Aminotransferases - AST and ALT are moderately elevated, with AST > ALT. However, normal aminotransferases do not preclude cirrhosis.
* Alkaline phosphatase - usually slightly elevated.
* Gamma-glutamyl transferase – correlates with AP levels. Typically much higher in chronic liver disease from alcohol.
* Bilirubin - may elevate as cirrhosis progresses.
* Albumin - levels fall as the synthetic function of the liver declines with worsening cirrhosis since albumin is exclusively synthesized in the liver
* Prothrombin time - increases since the liver synthesizes clotting factors.
* Globulins - increased due to shunting of bacterial antigens away from the liver to lymphoid tissue.
* Serum sodium - hyponatremia due to inability to excrete free water resulting from high levels of ADH and aldosterone.
* Thrombocytopenia - due to both congestive splenomegaly as well as decreased thrombopoietin from the liver. However, this rarely results in platelet count < 50,000/mL.
* Leukopenia and neutropenia - due to splenomegaly with splenic margination.
* Coagulation defects - the liver produces most of the coagulation factors and thus coagulopathy correlates with worsening liver disease.
There is now a validated and patented combination of 6 of these markers as non-invasive biomarker of fibrosis (and so of cirrhosis) : FibroTest.
Other laboratory studies performed in newly diagnosed cirrhosis may include:
* Serology for hepatitis viruses, autoantibodies (ANA, anti-smooth muscle, anti-mitochondria, anti-LKM)
* Ferritin and transferrin saturation (markers of iron overload), copper and ceruloplasmin (markers of copper overload)
* Immunoglobulin levels (IgG, IgM, IgA) - these are non-specific but may assist in distinguishing various causes
* Cholesterol and glucose
* Alpha 1-antitrypsin
Macroscopically, the liver is initially enlarged, but with progression of the disease, it becomes smaller. Its surface is irregular, the consistency is firm and the color is often yellow (if associates steatosis). Depending on the size of the nodules there are three macroscopic types: micronodular, macronodular and mixed cirrhosis. In micronodular form (Laennec's cirrhosis or portal cirrhosis) regenerating nodules are under 3 mm. In macronodular cirrhosis (post-necrotic cirrhosis), the nodules are larger than 3 mm. The mixed cirrhosis consists in a variety of nodules with different sizes.
However, cirrhosis is defined by its pathological features on microscopy: (1) the presence of regenerating nodules of hepatocytes and (2) the presence of fibrosis, or the deposition of connective tissue between these nodules. The pattern of fibrosis seen can depend upon the underlying insult that led to cirrhosis; fibrosis can also proliferate even if the underlying process that caused it has resolved or ceased. The fibrosis in cirrhosis can lead to destruction of other normal tissues in the liver: including the sinusoids, the space of Disse, and other vascular structures, which leads to altered resistance to blood flow in the liver and portal hypertension.
Cirrhosis and chronic liver disease were the 10th leading cause of death for men and the 12th for women in the United States in 2001, killing about 27,000 people each year. Also, the cost of cirrhosis in terms of human suffering, hospital costs, and lost productivity is high.
Established cirrhosis has a 10-year mortality of 34-66%, largely dependent on the cause of the cirrhosis; alcoholic cirrhosis has a worse prognosis than primary biliary cirrhosis and cirrhosis due to hepatitis. The risk of death due to all causes is increased twelvefold; if one excludes the direct consequences of the liver disease, there is still a fivefold increased risk of death in all disease categories.
Little is known on modulators of cirrhosis risk, apart from other diseases that cause liver injury (such as the combination of alcoholic liver disease and chronic viral hepatitis, which may act synergistically in leading to cirrhosis). Studies have recently suggested that coffee consumption may protect against cirrhosis, especially alcoholic cirrhosis.
