Cirrhosis


Cirrhosis, also known as liver cirrhosis or hepatic cirrhosis, is a condition in which the liver does not function properly due to long-term damage. This damage is characterized by the replacement of normal liver tissue by scar tissue. Typically, the disease develops slowly over months or years. Early on, there are often no symptoms. As the disease worsens, a person may become tired, weak, itchy, have swelling in the lower legs, develop yellow skin, bruise easily, have fluid buildup in the abdomen, or develop spider-like blood vessels on the skin. The fluid build-up in the abdomen may become spontaneously infected. Other serious complications include hepatic encephalopathy, bleeding from dilated veins in the esophagus or dilated stomach veins, and liver cancer. Hepatic encephalopathy results in confusion and may lead to unconsciousness.
Cirrhosis is most commonly caused by alcohol, hepatitis B, hepatitis C, and non-alcoholic fatty liver disease. Typically, more than two or three alcoholic drinks per day over a number of years is required for alcoholic cirrhosis to occur. Non-alcoholic fatty liver disease has a number of causes, including being overweight, diabetes, high blood fats, and high blood pressure. A number of less common causes of cirrhosis include autoimmune hepatitis, primary biliary cholangitis, hemochromatosis, certain medications, and gallstones. Diagnosis is based on blood testing, medical imaging, and liver biopsy.
Some causes of cirrhosis, such as hepatitis B, can be prevented by vaccination. Treatment partly depends on the underlying cause, but the goal is often to prevent worsening and complications. Avoiding alcohol is recommended in all cases of cirrhosis. Hepatitis B and C may be treatable with antiviral medications. Autoimmune hepatitis may be treated with steroid medications. Ursodiol may be useful if the disease is due to blockage of the bile ducts. Other medications may be useful for complications such as abdominal or leg swelling, hepatic encephalopathy, and dilated esophageal veins. In severe cirrhosis, a liver transplant may be an option.
Cirrhosis affected about 2.8 million people and resulted in 1.3 million deaths in 2015. Of these deaths, alcohol caused 348,000, hepatitis C caused 326,000, and hepatitis B caused 371,000. In the United States, more men die of cirrhosis than women. The first known description of the condition is by Hippocrates in the 5th century BCE. The term cirrhosis was invented in 1819, from a Greek word for the yellowish color of a diseased liver.

Signs and symptoms

Cirrhosis has many possible manifestations. These signs and symptoms may be either a direct result of the failure of liver cells, or secondary to the resultant increased pressure in the blood vessels in the hepatic portal system. Some manifestations of cirrhosis are nonspecific, and also occur in several unrelated conditions. Likewise, the absence of any signs does not rule out the possibility of cirrhosis. Cirrhosis of the liver is slow and gradual in its development. It is usually well advanced before its symptoms are noticeable enough to cause alarm. Weakness and weight loss may be early symptoms.

Liver dysfunction

The following features are as a direct consequence of liver cells not functioning.
Liver cirrhosis increases resistance to blood flow and leads to higher pressure in the portal venous system, resulting in portal hypertension. Effects of portal hypertension include:
There are some changes seen in cirrhosis whose causes are not clearly known. They may also be a sign of other non-liver related causes.
As the disease progresses, complications may develop. In some people, these may be the first signs of the disease.
Liver cirrhosis has many possible causes; sometimes more than one cause is present in the same person. Globally, 57% of cirrhosis is attributable to either hepatitis B or hepatitis C. Alcohol consumption is another major cause, accounting for about 20% of the cases.
The liver plays a vital role in synthesis of proteins, detoxification, and storage. In addition, it participates in the metabolism of lipids and carbohydrates.
Cirrhosis is often preceded by hepatitis and fatty liver, independent of the cause. If the cause is removed at this stage, the changes are fully reversible.
The pathological hallmark of cirrhosis is the development of scar tissue that replaces normal parenchyma. This scar tissue blocks the portal flow of blood through the organ, raising the blood pressure 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 stellate cells, which increases fibrosis and obstructs hepatic blood flow. In addition, stellate cells secrete 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 the fibrotic material in the extracellular matrix.
As this cascade of processes continues, fibrous tissue bands 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 the spleen's retention of platelets, which are needed for normal blood clotting. Portal hypertension is responsible for the most severe complications of cirrhosis.

Diagnosis

The gold standard for diagnosis of cirrhosis is a liver biopsy, through a percutaneous, transjugular, laparoscopic, or fine-needle approach. A biopsy is not necessary if the clinical, laboratory, and radiologic data suggests cirrhosis. Furthermore, there is a small but significant risk of complications from liver biopsy, and cirrhosis itself predisposes for complications caused by liver biopsy.
ScorePlatelet count x109ALT/AST ratioINR
0>340>1.7<1.1
1280-3401.2-1.71.1-1.4
2220-2790.6-1.19>1.4
3160-219<0.6...
4100-159......
540-99......
6<40......

The best predictors of cirrhosis are ascites, platelet count < 160,000/mm3, spider angiomata, and a Bonacini cirrhosis discriminant score greater than 7.

Lab findings

The following findings are typical in cirrhosis:
FibroTest is a biomarker for fibrosis that can be done instead of a biopsy.
Other laboratory studies performed in newly diagnosed cirrhosis may include:
is routinely used in the evaluation of cirrhosis. It may show a small and nodular liver in advanced cirrhosis along with increased echogenicity with irregular appearing areas. Other liver findings suggestive of cirrhosis in imaging are an enlarged caudate lobe, widening of the fissures and enlargement of the spleen. An enlarged spleen, which normally measures less than 11–12 cm in adults, can be seen and may suggest underlying portal hypertension. Ultrasound may also screen for hepatocellular carcinoma, portal hypertension, and Budd-Chiari syndrome. An increased portal vein pulsatility is an indicator of cirrhosis, but may also be caused by an increased right atrial pressure. Portal vein pulsatility can be quantified by pulsatility indices, where an index above a certain cutoff indicates pathology:
IndexCalculationCutoff
Average-based / Average0.5
Max-relative / Max0.5–0.54

Cirrhosis is diagnosed with a variety of elastography techniques. Because a cirrhotic liver is generally stiffer than a healthy one, imaging the liver's stiffness can give diagnostic information about the location and severity of cirrhosis. Techniques used include transient elastography, acoustic radiation force impulse imaging, supersonic shear imaging and magnetic resonance elastography. Compared to a biopsy, elastography can sample a much larger area and is painless. It shows a reasonable correlation with the severity of cirrhosis.
Other tests performed in particular circumstances include abdominal CT and liver/bile duct MRI.

Endoscopy

is performed in patients with established cirrhosis to exclude the possibility of esophageal varices. If these are found, prophylactic local therapy may be applied and beta blocker treatment may be commenced.
Rarely are diseases of the bile ducts, such as primary sclerosing cholangitis, causes of cirrhosis. Imaging of the bile ducts, such as ERCP or MRCP may aid in the diagnosis.

Pathology

Macroscopically, the liver is initially enlarged, but with the progression of the disease, it becomes smaller. Its surface is irregular, the consistency is firm, and the color is often yellow. Depending on the size of the nodules, there are three macroscopic types: micronodular, macronodular, and mixed cirrhosis. In the micronodular form, regenerating nodules are under 3 mm. In macronodular cirrhosis, the nodules are larger than 3 mm. Mixed cirrhosis consists of nodules of different sizes.
However, cirrhosis is defined by its pathological features on microscopy: the presence of regenerating nodules of hepatocytes and the presence of fibrosis, or the deposition of connective tissue between these nodules. The pattern of fibrosis seen can depend on 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.
As cirrhosis can be caused by many different entities which injure the liver in different ways, cause-specific abnormalities may be seen. For example, in chronic hepatitis B, there is infiltration of the liver parenchyma with lymphocytes. In cardiac cirrhosis there are erythrocytes and a greater amount of fibrosis in the tissue surrounding the hepatic veins. In primary biliary cholangitis, there is fibrosis around the bile duct, the presence of granulomas and pooling of bile. Lastly in alcoholic cirrhosis, there is infiltration of the liver with neutrophils.

Grading

The severity of cirrhosis is commonly classified with the Child-Pugh score. This scoring system uses bilirubin, albumin, INR, the presence and severity of ascites, and encephalopathy to classify patients into class A, B, or C. Class A has a favourable prognosis, while class C is at high risk of death. This system was devised in 1964 by Child and Turcotte, and modified in 1973 by Pugh and others.
More modern scores, used in the allocation of liver transplants but also in other contexts, are the Model for End-Stage Liver Disease score and its pediatric counterpart, the Pediatric End-Stage Liver Disease score.
The hepatic venous pressure gradient, also determines the severity of cirrhosis, although it is hard to measure. A value of 16 mm or more means a greatly increased risk of death.

Prevention

Key prevention strategies for cirrhosis are population-wide interventions to reduce alcohol intake, programs to reduce the transmission of viral hepatitis, and screening of relatives of people with hereditary liver diseases.
Little is known about factors affecting cirrhosis risk and progression. Research has suggested that coffee consumption appears to help protect against cirrhosis.

Treatment

Generally, liver damage from cirrhosis cannot be reversed, but treatment can stop or delay further progression and reduce complications. A healthy diet is encouraged, as cirrhosis may be an energy-consuming process. Close follow-up is often necessary. Antibiotics are prescribed for infections, and various medications can help with itching. Laxatives, such as lactulose, decrease the risk of constipation; their role in preventing encephalopathy is limited.
Alcoholic cirrhosis caused by alcohol abuse is treated by abstaining from alcohol. Treatment for hepatitis-related cirrhosis involves medications used to treat the different types of hepatitis, such as interferon for viral hepatitis and corticosteroids for autoimmune hepatitis. Cirrhosis caused by Wilson's disease, in which copper builds up in organs, is treated with chelation therapy to remove the copper.

Preventing further liver damage

Regardless of the underlying cause of cirrhosis, consumption of alcohol and paracetamol, as well as other potentially damaging substances, are discouraged. Vaccination of susceptible patients should be considered for Hepatitis A and Hepatitis B.
Treating the cause of cirrhosis prevents further damage; for example, giving oral antivirals such as entecavir and tenofovir in patients of cirrhosis due to Hepatitis B prevents progression of cirrhosis. Similarly, control of weight and diabetes prevents deterioration in cirrhosis due to Non-alcoholic steatohepatitis.

Transplantation

If complications cannot be controlled or when the liver ceases functioning, liver transplantation is necessary. Survival from liver transplantation has been improving over the 1990s, and the five-year survival rate is now around 80%. The survival rate depends largely on the severity of disease and other medical risk factors in the recipient. In the United States, the MELD score is used to prioritize patients for transplantation. Transplantation necessitates the use of immune suppressants.

Decompensated cirrhosis

Manifestations of decompensation in cirrhosis include gastrointestinal bleeding, hepatic encephalopathy, jaundice or ascites. In patients with previously stable cirrhosis, decompensation may occur due to various causes, such as constipation, infection, increased alcohol intake, medication, bleeding from esophageal varices or dehydration. It may take the form of any of the complications of cirrhosis listed below.
People with decompensated cirrhosis generally require admission to a hospital, with close monitoring of the fluid balance, mental status, and emphasis on adequate nutrition and medical treatment – often with diuretics, antibiotics, laxatives or enemas, thiamine and occasionally steroids, acetylcysteine and pentoxifylline. Administration of saline is avoided, as it would add to the already high total body sodium content that typically occurs in cirrhosis. Life expectancy without liver transplant is low, at most 3 years.

Palliative care

is specialized medical care that focuses on providing patients with relief from the symptoms, pain, and stress of a serious illness, such as cirrhosis. The goal of palliative care is to improve quality of life for both the patient and the patient's family and it is appropriate at any stage and for any type of cirrhosis.
Especially in the later stages, people with cirrhosis experience significant symptoms such as abdominal swelling, itching, leg edema, and chronic abdominal pain which would be amenable for treatment through palliative care. Because the disease is not curable without a transplant, palliative care can also help with discussions regarding the person's wishes concerning health care power of attorney, Do Not Resuscitate decisions and life support, and potentially hospice. Despite proven benefit, people with cirrhosis are rarely referred to palliative care.

Complications

Ascites

Salt restriction is often necessary, as cirrhosis leads to accumulation of salt. Diuretics may be necessary to suppress ascites. Diuretic options for inpatient treatment include aldosterone antagonists and loop diuretics. Aldosterone antagonists are preferred for people who can take oral medications and are not in need of an urgent volume reduction. Loop diuretics can be added as additional therapy.
If a rapid reduction of volume is required, paracentesis is the preferred option. This procedure requires the insertion of a plastic tube into the peritoneal cavity. Human albumin solution is usually given to prevent complications from the rapid volume reduction. In addition to being more rapid than diuretics, 4–5 liters of paracentesis is more successful in comparison to diuretic therapy.

Esophageal variceal bleeding

For portal hypertension, nonselective beta blockers such as propranolol or nadolol are commonly used to lower blood pressure over the portal system. In severe complications from portal hypertension, transjugular intrahepatic portosystemic shunting is occasionally indicated to relieve pressure on the portal vein. As this shunting can worsen hepatic encephalopathy, it is reserved for those patients at low risk of encephalopathy. TIPS is generally regarded only as a bridge to liver transplantation or as a palliative measure.

Hepatic encephalopathy

High-protein food increases the nitrogen balance, and would theoretically increase hepatic encephalopathy; in the past, a low-protein diet was recommended. Recent studies show that this assumption was incorrect, and high-protein foods are even encouraged to maintain adequate nutrition.

Hepatorenal syndrome

The hepatorenal syndrome is defined as a urine sodium less than 10 mmol/L and a serum creatinine > 1.5 mg/dl after a trial of volume expansion without diuretics.

Spontaneous bacterial peritonitis

People with ascites due to cirrhosis are at risk of spontaneous bacterial peritonitis.

Portal hypertensive gastropathy

This refers to changes in the mucosa of the stomach in people with portal hypertension, and is associated with cirrhosis severity.

Infection

Cirrhosis can cause immune system dysfunction, leading to infection. Signs and symptoms of infection may be nonspecific and are more difficult to recognize.

Hepatocellular carcinoma

is a primary liver cancer that is more common in people with cirrhosis. People with known cirrhosis are often screened intermittently for early signs of this tumor, and screening has been shown to improve outcomes.

Epidemiology

Cirrhosis and chronic liver disease were the tenth leading cause of death for men and the twelfth for women in the United States in 2001, killing about 27,000 people each year. The cost of cirrhosis in terms of human suffering, hospital costs, and lost productivity is high. Cirrhosis is more common in men than in women.
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 cholangitis 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.

Etymology

The word "cirrhosis" is a neologism derived from κίρρωσις; kirrhos κιρρός, meaning "yellowish, tawny" and the suffix -osis, i.e. "condition" in medical terminology. While the clinical entity was known before, René Laennec gave it this name in an 1819 paper.