It actually covers liver pathology resulting from excessive alcohol consumption. Alcohol-related liver disease includes various liver disorders, starting from simple fatty liver (steatosis) and ranging to alcoholic hepatitis, cirrhosis, and even liver cancer. It is mostly a condition where damage arises from the toxic effect of alcohol on liver cells. As the metabolic organ for alcohol, the liver is the most sensitive organ to damage from high alcohol consumption. Excessive alcohol consumption can lead to excessive metabolic activity of the liver that causes damage through inflammation, fat deposition, fibrosis, or ultimately scarring of liver tissue. The pathophysiology of alcohol-related liver disease involves a complex series of events such as metabolism of alcohol, oxidative stress, cellular dysfunction of the immune system, and genetic predisposing factors.
Once consumed, alcohol enters the bloodstream and is transferred to the liver where it is metabolized primarily by enzymes such as alcohol dehydrogenase (ADH) and cytochrome P450 2E1. These enzymes break down alcohol into acetaldehyde, then into acetate and finally eliminate it from the body. However, acetaldehyde is a toxic compound – and its accumulation after excessive drinking can have serious damaging effects on liver cells with increased production of free radicals and subsequent inflammatory reactions. The inflammatory process fails to aid in liver cell repair, instead, it produces the following: liver cell injury; cell death; and secretion of various cytokines that damage the liver.
As a result of alcoholism, early-onset alcoholic liver disease results in what is known as alcoholic fatty liver disease (AFLD). AFLD is characterized by the accumulation of fat within liver cells without any appreciable concurrent inflammation. This condition is reversible, meaning that by reducing or stopping alcohol intake the liver will recover and the fat will be cleared. In contrast, continued alcohol consumption can cause AFLD to develop into more severe liver damage. The transition from fatty liver to alcoholic hepatitis is characterized by inflammation in the liver tissue. At this point in the disease, it may present with symptoms such as jaundice, abdominal pain, fever, vomiting, and risk of liver failure.
Alcoholic hepatitis refers to an advanced state of degeneration of alcohol-related liver disease. It manifests as inflammation in the liver that is mostly associated with necrosis and fibrosis of the liver cells. Very severe alcoholic hepatitis can cause such severe liver dysfunction that patients often develop symptoms such as jaundice, ascites and hepatic encephalopathy, a condition that appears when the organ fails to maintain normal brain function. The severity of alcoholic hepatitis can range from mild to potentially fatal, depending on the amount of liver damage, the person's general health and the level of alcohol consumption. Long-term alcohol abuse can lead to recurrences of alcoholic hepatitis, which can worsen liver damage.
The most advanced stage of alcoholic liver disease, which occurs from long-term alcohol consumption, is called cirrhosis. This condition is marked by the presence of scar tissue in the liver due to injury and inflammation of liver cells over time. The formation of scarring disrupts the structure and function of the liver normally and causes problems with blood flow and sinuses, preventing the liver from performing its essential activities, such as detoxifying harmful substances, producing proteins, and regulating blood sugar. Thus, cirrhosis involves a number of complications, such as portal hypertension (increased pressure in the veins that supply the liver), varices (enlarged blood vessels that can cause bleeding), liver failure, and hepatocellular carcinoma. Liver function is often irreversibly impaired when cirrhosis develops, and without transplantation it can be fatal.
It should be noted that not everyone who drinks too much alcohol will develop alcoholic liver disease. The configuration that results in the development of alcohol-related liver disease depends on the amount of alcohol consumed per occasion and how long the person has been consuming alcohol; genetic factors; sex; the person's age at the stage of alcohol consumption; nutritional intake; and other pre-existing liver diseases such as viral hepatitis. For example, women develop alcoholic liver injury at a lower rate than men. It is believed that this is due to differences in alcohol metabolism, hormones, and body composition. In addition, people who have a genetic predisposition to certain liver diseases, such as mutations in the gene encoding for alcohol dehydrogenase or those with the HFE gene responsible for hemochromatosis, may also have an increased risk of developing this ARLD.
Alcohol-related liver disease often requires the use of multiple modalities that include obtaining a clinical history, physical examination, laboratory and imaging studies, and may also require a liver biopsy. A detailed history of alcohol consumption is important for risk assessment of ARLD as well as appropriate liver function tests that evaluate hepatic enzymes including ALT, AST, bilirubin, and clotting factors. Imaging modalities such as ultrasound and CT can evaluate the liver in terms of its size, texture, and the presence of fibrosis or cirrhosis. In some cases, the extent of liver damage can be determined by liver biopsy, especially when the diagnosis is uncertain or to assess the degree of inflammation and fibrosis.
Cessation or reduction of alcohol consumption is the cornerstone of lifestyle modification-focused management of alcohol-related liver disease. Abstinence from alcohol provides the liver with an opportunity to recover and prevent any further damage and is the mainstay of prevention of potential worsening – even more so in cases of alcoholic fatty liver disease. Severe forms of ARLD such as alcoholic hepatitis and cirrhosis may also require medical management to improve complications and symptoms. This may include corticosteroid administration to reduce the inflammatory process in alcoholic hepatitis and pentoxifylline or azathioprine to prevent liver inflammation in some cases. Management in patients with cirrhosis revolves around the treatment of complications such as ascites, portal hypertension and various types of bleeding. Liver transplantation may be required in end-stage liver failure or in patients with alcohol-related cirrhosis who suffer from liver failure.
Both public health and individual behavior change are critical to preventing alcohol-related liver diseases. Such public health measures, which include awareness, education, screening for alcohol use disorders, and interventions to decrease alcohol consumption, should work alongside individual measures that recommend either reducing alcohol intake or—most effectively—advising its complete avoidance to avoid alcohol's effects. General MA will set one drink intake by the age range of less than two drinks per day as a lower estimate of this limit for these two categories in lieu of a numerical definition of one drink, such as approximately 14 grams of pure alcohol, equivalent to 12 ounces of beer or 5 ounces of wine, or 1.5 ounces of distilled spirits. Developmentally, on the other hand, no safe level of consumption is available for any person with pre-existing liver disease or a person at risk of ARLD development.
This is undoubtedly a very serious public health issue worldwide—alcohol-related liver diseases are responsible for a very large amount of liver morbidity and mortality. Alcohol is counted among the first few causes of cirrhosis and liver cancer—the incidence is alarmingly high in regions where drinking is a permanent part of the local culture. Concern is emerging because the proportion of young people drinking to excess and especially excessive drinking is rapidly increasing, and there are concerns about what impact this will have on the incidence of alcohol-related liver disease in the future. The prevention of this problem among ARLD subjects thus requires a combination of early detection and treatment with prevention to improve the overall health and well-being of at-risk individuals.
