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Key prevention strategies for cirrhosis are population-wide interventions to reduce alcohol intake (through pricing strategies, public health campaigns, and personal counseling), 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.
Chronic liver diseases like chronic hepatitis, chronic alcohol abuse or chronic toxic liver disease may cause
- liver failure and hepatorenal syndrome
- fibrosis and cirrhosis of liver
Cirrhosis may also occur in primary biliary cirrhosis. Rarely, cirrhosis is congenital.
This includes mostly drug-induced hepatotoxicity, (DILI) which may generate many different patterns over liver disease, including
- cholestasis
- necrosis
- acute hepatitis and chronic hepatitis of different forms,
- cirrhosis
- Effects of Acetaminophen (Tylenol)
- other rare disorders like focal nodular hyperplasia, Hepatic fibrosis, peliosis hepatis and veno-occlusive disease.
Liver damage is part of Reye's syndrome.
People with ascites due to cirrhosis are at risk of spontaneous bacterial peritonitis.
HCC mostly occurs in people with cirrhosis of the liver, and so risk factors generally include factors which cause chronic liver disease that may lead to cirrhosis. Still, certain risk factors are much more highly associated with HCC than others. For example, while heavy alcohol consumption is estimated to cause 60-70% of cirrhosis, the vast majority of HCC occurs in cirrhosis attributed to viral hepatitis (although there may be overlap). Recognized risk factors include:
- Chronic viral hepatitis (estimated cause of 80% cases globally)
- Chronic hepatitis B (approximately 50% cases)
- Chronic hepatitis C (approximately 25% cases)
- Toxins:
- Alcohol abuse: the most common cause of cirrhosis
- Aflatoxin
- Iron overload state (Hemochromatosis)
- Metabolic:
- Nonalcoholic steatohepatitis: up to 20% progress to cirrhosis
- Type 2 diabetes (probably aided by obesity)
- Congenital disorders:
- Alpha 1-antitrypsin deficiency
- Wilson's disease (controversial; while some theorise the risk increases, case studies are rare and suggest the opposite where Wilson's disease actually may confer protection)
- Hemophilia, although statistically associated with higher risk of HCC, this is due to coincident chronic viral hepatitis infection related to repeated blood transfusions over lifetime.
The significance of these risk factors varies globally. In regions where hepatitis B infection is endemic, such as southeast China, this is the predominant cause. In populations largely protected by hepatitis B vaccination, such as the United States, HCC is most often linked to causes of cirrhosis such as chronic hepatitis C, obesity, and alcohol abuse.
Certain benign liver tumors, such as hepatocellular adenoma, may sometimes be associated with coexisting malignant HCC. There is limited evidence for the true incidence of malignancy associated with benign adenomas; however, the size of hepatic adenoma is considered to correspond to risk of malignancy and so larger tumors may be surgically removed. Certain subtypes of adenoma, particularly those with β-catenin activation mutation, are particularly associated with increased risk of HCC.
Children and adolescents are unlikely to have chronic liver disease, however, if they suffer from congenital liver disorders, this fact increases the chance of developing hepatocellular carcinoma. Specifically, children with biliary atresia, infantile cholestasis, glycogen-storage diseases, and other cirrhotic diseases of the liver are predisposed to developing HCC in childhood.
Young adults afflicted by the rare fibrolamellar variant of hepatocellular carcinoma may have none of the typical risk factors, i.e. cirrhosis and hepatitis.
Chronic sclerosing sialadenitis is a chronic (long-lasting) inflammatory condition affecting the salivary gland. Relatively rare in occurrence, this condition is benign, but presents as hard, indurated and enlarged masses that are clinically indistinguishable from salivary gland neoplasms or tumors. It is now regarded as a manifestation of IgG4-related disease.
Involvement of the submandibular glands is also known as Küttner's tumor, named after Hermann Küttner (1870–1932), a German Oral and Maxillofacial Surgeon, who reported four cases of submandibular gland lesions for the first time in 1896.
The risk factors presently known are:
- Quantity of alcohol taken: Consumption of 60–80g per day (14g is considered one standard drink in the USA, i.e., 1.5 fl oz hard liquor, 5 fl oz wine, 12 fl oz beer; drinking a six-pack of beer daily would be in the middle of the range) for 20 years or more in men, or 20g/day for women significantly increases the risk of hepatitis and fibrosis by 7% to 47%,
- Pattern of drinking: Drinking outside of meal times increases up to 3 times the risk of alcoholic liver disease.
- Gender: Women are twice as susceptible to alcohol-related liver disease, and may develop alcoholic liver disease with shorter durations and doses of chronic consumption. The lesser amount of alcohol dehydrogenase secreted in the gut, higher proportion of body fat in women, and changes in fat absorption due to the menstrual cycle may explain this phenomenon.
- Hepatitis C infection: A concomitant hepatitis C infection significantly accelerates the process of liver injury.
- Genetic factors: Genetic factors predispose both to alcoholism and to alcoholic liver disease. Both monozygotic twins are more likely to be alcoholics and to develop liver cirrhosis than both dizygotic twins. Polymorphisms in the enzymes involved in the metabolism of alcohol, such as ADH, ALDH, CYP4502E1, mitochondrial dysfunction, and cytokine polymorphism may partly explain this genetic component. However, no specific polymorphisms have currently been firmly linked to alcoholic liver disease.
- Iron overload (Hemochromatosis)
- Diet: Malnutrition, particularly vitamin A and E deficiencies, can worsen alcohol-induced liver damage by preventing regeneration of hepatocytes. This is particularly a concern as alcoholics are usually malnourished because of a poor diet, anorexia, and encephalopathy.
The prevalence of FLD in the general population ranges from 10% to 24% in various countries. However, the condition is observed in up to 75% of obese people, 35% of whom progress to NAFLD, despite no evidence of excessive alcohol consumption. FLD is the most common cause of abnormal liver function tests in the United States. "Fatty livers occur in 33% of European-Americans, 45% of Hispanic-Americans, and 24% of African-Americans."
Mild disease has a risk of death of about 10% while moderate disease has a risk of death of 20%. When it occurs as a result of bone marrow transplant and multiorgan failure is present, the risk of death is greater than 80%.
The prognosis for people with ALD depends on the liver histology as well as cofactors, such as concomitant chronic viral hepatitis. Among patients with alcoholic hepatitis, progression to liver cirrhosis occurs at 10–20% per year, and 70% will eventually develop cirrhosis. Despite cessation of alcohol use, only 10% will have normalization of histology and serum liver enzyme levels. As previously noted, the MDF has been used to predict short-term mortality (i.e., MDF ≥ 32 associated with spontaneous survival of 50–65% without corticosteroid therapy, and MDF 11) and 90-day (MELD > 21) mortality. Liver cirrhosis develops in 6–14% of those who consume more than 60–80 g of alcohol daily for men and more than 20 g daily for women. Even in those who drink more than 120 g daily, only 13.5% will suffer serious alcohol-related liver injury. Nevertheless, alcohol-related mortality was the third leading cause of death in 2003 in the United States. Worldwide mortality is estimated to be 150,000 per year.
The cause and pathogenesis of this chronic condition are not very well understood. Several factors have been postulated:
- Formation of a hard salivary calculus or sialolith by accumulation of calcium salts in the duct of the salivary gland (a process known as Sialolithiasis). This has been proposed as the most common cause for Küttner's tumor of the submandibular gland, with sialoliths observed in an appreciable proportion of cases. However, sialolith involvement may not be found in many cases.
- Abnormalities of the salivary gland ducts leading to excessive accumulation or retention of ductal secretions, which can excite chronic inflammations.
- Immune, especially autoimmune, cause - which has gained steam, given the observation that the tissue of the glands is overrun with lymphoid immune cells and fibrous connective tissue, as well as corroboration from markedly similar lesions (with histologic and immunohistochemical findings) seen elsewhere in the body. The presence of abundant Immunoglobulin G4 (IgG4) associated with Plasma cells infiltrating into the salivary glands, as well as increased serum IgG4 concentration, has been noted with patients with Küttner's tumor.
This chronic condition is primarily observed in adult (40–70 years) patients. However, Küttner's tumor, with prominent immunopathological features, has been described in an 11-year-old boy in Brazil in 2012.
The condition is usually congenital, but sporadic cases have also been reported. It may be associated with other congenital defects, commonly with autosomal recessive polycystic kidney disease, the most severe form of PKD. Some suggest that these two conditions are one disorder with different presentation.
Approximately 15,000 new cases of liver and biliary tract carcinoma are diagnosed annually in the United States, with roughly 10% of these cases being Klatskin tumors. Cholangiocarcinoma accounts for approximately 2% of all cancer diagnoses, with an overall incidence of 1.2/100,000 individuals. Two-thirds of cases occur in patients over the age of 65, with a near ten-fold increase in patients over 80 years of age. The incidence is similar in both men and women.
"Acute on chronic liver failure" is said to exist when someone with chronic liver disease develops features of liver failure. A number of underlying causes may precipitate this, such as alcohol misuse or infection. People with ACLF can be critically ill and require intensive care treatment, and occasionally a liver transplant. Mortality with treatment is 50%.
The majority of hepatic adenomas arise in women aged 20–40, most of whom use oral contraceptives. Other medications which also alter circulating hormone levels, such as anabolic or androgenic steroids, barbituates, clomifene, have also been implicated as risk factors.
Incidence of adenomas may be increased in metabolic diseases, including tyrosinemia and type 1 diabetes mellitus, and glycogen storage diseases (types 1 and 3), as well as in beta-thalassemia and hemochromatosis.
This large, atypical haemangioma of the liver may present with abdominal pain or fullness due to haemorrhage, thrombosis or mass effect. It may also lead to left ventricular volume overload and heart failure due to the increase in cardiac output which it causes. Further complications are Kasabach-Merritt syndrome, a form of consumptive coagulopathy due to thrombocytopaenia, and rupture.
The risk of hepatocellular carcinoma in type 2 diabetics is greater (from 2.5 to 7.1 times the non diabetic risk) depending on the duration of diabetes and treatment protocol. A suspected contributor to this increased risk is circulating insulin concentration such that diabetics with poor insulin control or on treatments that elevate their insulin output (both states that contribute to a higher circulating insulin concentration) show far greater risk of hepatocellular carcinoma than diabetics on treatments that reduce circulating insulin concentration. On this note, some diabetics who engage in tight insulin control (by keeping it from being elevated) show risk levels low enough to be indistinguishable from the general population. This phenomenon is thus not isolated to diabetes mellitus type 2 since poor insulin regulation is also found in other conditions such as metabolic syndrome (specifically, when evidence of non alcoholic fatty liver disease or NAFLD is present) and again there is evidence of greater risk here too. While there are claims that anabolic steroid abusers are at greater risk (theorized to be due to insulin and IGF exacerbation), the only evidence that has been confirmed is that anabolic steroid users are more likely to have hepatocellular adenomas (a benign form of HCC) transform into the more dangerous hepatocellular carcinoma.
Fatty liver (FL) is commonly associated with alcohol or metabolic syndrome (diabetes, hypertension, obesity, and dyslipidemia), but can also be due to any one of many causes:
- Metabolic: abetalipoproteinemia, glycogen storage diseases, Weber–Christian disease, acute fatty liver of pregnancy, lipodystrophy
- Nutritional:malnutrition, total parenteral nutrition, severe weight loss, refeeding syndrome, jejunoileal bypass, gastric bypass, jejunal diverticulosis with bacterial overgrowth
- Drugs and toxins: amiodarone, methotrexate, diltiazem, expired tetracycline, highly active antiretroviral therapy, glucocorticoids, tamoxifen, environmental hepatotoxins (e.g., phosphorus, mushroom poisoning)
- Alcohol: Alcoholism is one of the major causes of fatty liver due to production of toxic metabolites like aldehydes during metabolism of alcohol in the liver. This phenomenon most commonly occurs with chronic alcoholism.
- Other: celiac disease, inflammatory bowel disease, HIV, hepatitis C (especially genotype 3), and alpha 1-antitrypsin deficiency
Liver disease can occur through several mechanisms. A common form of liver disease is viral infection. Viral hepatitides such as Hepatitis B virus and Hepatitis C virus can be vertically transmitted during birth via contact with infected blood. According to a 2012 NICE publication, "about 85% of hepatitis B infections in newborns become chronic". In occult cases, Hepatitis B virus is present by HBV DNA, but testing for HBsAg is negative. High consumption of alcohol can lead to several forms of liver disease including alcoholic hepatitis, alcoholic fatty liver disease, cirrhosis, and liver cancer. In the earlier stages of alcoholic liver disease, fat builds up in the liver's cells due to increased creation of triglycerides and fatty acids and a decreased ability to break down fatty acids. Progression of the disease can lead to liver inflammation from the excess fat in the liver. Scarring in the liver often occurs as the body attempts to heal and extensive scarring can lead to the development of cirrhosis in more advanced stages of the disease. Approximately 3–10% of individuals with cirrhosis develop a form of liver cancer known as hepatocellular carcinoma.
According to Tilg, et al., gut microbiome could very well have an effect, be involved in the pathophysiology, on the various types of liver disease which an individual may encounter.
Because of their location, these tumors tend to become symptomatic late in their development and therefore are not usually resectable at the time of presentation. This is variable as, due to obstruction, jaundice may present early and compel the patient to seek help. Complete resection of the tumor offers hope of long-term survival, and of late there has been renewed interest in liver transplantation from deceased donors along with add on therapy. Prognosis remains poor.
Anti-viral medications are available to treat infections such as hepatitis B. Other conditions may be managed by slowing down disease progression, for example:
- By using steroid-based drugs in autoimmune hepatitis.
- Regularly removing a quantity of blood from a vein (venesection) in the iron overload condition, hemochromatosis.
- Wilson’s disease, a condition where copper builds up in the body, can be managed with drugs which bind copper allowing it to be passed from your body in urine.
- In cholestatic liver disease, (where the flow of bile is affected due to cystic fibrosis) a medication called ursodeoxycholic acid (URSO, also referred to as UDCA) may be given.
Embryogenically, congenital hepatic fibrosis is due to malformation of the duct plate, a round structure appearing in the eighth week of gestation that is formed by primitive hepatocytes, which differentiate into cholangiocytes. Congenital hepatic fibrosis usually presents in adolescent or young adulthood, but onset of signs and symptoms can range from early childhood through mid-life. Clinical features may vary but commonly include Cholangitis, hepatomegaly and signs of portal hypertension.
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.
Alcoholic hepatitis is hepatitis (inflammation of the liver) due to excessive intake of alcohol. It is usually found in association with fatty liver, an early stage of alcoholic liver disease, and may contribute to the progression of fibrosis, leading to cirrhosis. Signs and symptoms of alcoholic hepatitis include jaundice, ascites (fluid accumulation in the abdominal cavity), fatigue and hepatic encephalopathy (brain dysfunction due to liver failure). Mild cases are self-limiting, but severe cases have a high risk of death. Severe cases may be treated with glucocorticoids.
Clinical practice guidelines by the American College of Gastroenterology have recommended corticosteroid treatment. Patients should be risk stratified using a MELD Score or Child-Pugh score.
- Corticosteroids: These guidelines suggest that patients with a modified Maddrey's discriminant function score > 32 or hepatic encephalopathy should be considered for treatment with prednisolone 40 mg daily for four weeks followed by a taper. Models such as the Lille Model can be used to monitor for improvement or to consider alternative treatment.
- Pentoxifylline: A randomized controlled trial found that among patients with a discriminant function score > 32 and at least one of the following symptoms (a palpable, tender enlarged liver, fever, high white blood cell count, hepatic encephalopathy, or hepatic systolic bruit), 4.6 patients must be treated with pentoxifylline for 4 weeks to prevent one patient from dying. Subsequent trials have suggested that pentoxifylline may be superior to prednisolone in the management of acute alcoholic hepatitis with discriminant function score >32. Advantage of pentoxifylline over prednisolone was better tolerability, lesser side effects, with decreased occurrence of renal dysfunction in patients receiving pentoxifylline.
- Potential for combined therapy: A large prospective study of over 1000 patients investigated whether prednisolone and pentoxifylline produced benefits when used alone or in combination. Pentoxifylline did not improve survival alone or in combination. Prednisolone gave a small reduction in mortality at 28 days but this did not reach significance, and there were no improvements in outcomes at 90 days or 1 year.