- Clinical science
Alcoholic liver disease (ALD) refers to a range of progressive liver conditions caused by chronic and excessive alcohol consumption. One-third of the US population consumes alcohol above recommended levels, increasing their risk of ALD. There are three stages of ALD, which may or may not occur sequentially. The first stage involves the development of a potentially reversible alcoholic fatty liver, which is typically asymptomatic. Continued alcohol consumption may lead to alcoholic hepatitis, the second stage, which often becomes chronic. Clinical findings in this stage include jaundice, fatigue, and fever. In the last stage, the patient develops alcoholic cirrhosis. Patient history, transaminase levels, and imaging studies are crucial for diagnosis and show different patterns of hepatic injury. Non-alcoholic steatohepatitis is a differential diagnosis and is currently regarded as an important cause of cirrhosis. Treatment requires complete cessation of alcohol use.
- Second most common cause of liver cirrhosis in the United States
- 28% of the US population exceeds the recommended limits of alcohol consumption.
- Lifetime prevalence of alcohol abuse: 18%
- ∼ 10–20% of heavy drinkers develop cirrhosis.
Epidemiological data refers to the US, unless otherwise specified.
- is a very important cause of chronic liver diseases.
- Significant alcohol consumption
- Men: > 210 g pure alcohol per week
- Women: > 140 g pure alcohol per week
- Hepatic degradation of ethanol to acetyl-CoA by alcohol dehydrogenase results in NADH excess (see breakdown of ethanol for more details) → ↑ NADH drives the formation of glycerol 3-phosphate (G3P) from dihydroxyacetone phosphate (DHAP) → ↑ in both G3P and fatty acids causes increased triglyceride synthesis in the liver → steatohepatitis
The stages of ALD may overlap and do not necessarily occur in sequence.
Alcoholic fatty liver (reversible)
- Mostly asymptomatic
- A sensation of pressure in the upper abdominal area occurs in some patients.
- Hepatomegaly: soft in consistency
- Acute exacerbation with risk of hepatic failure occurs rarely.
Alcoholic hepatitis (reversible in mild cases)
- Nonspecific symptoms: nausea, loss of appetite, weight loss, low-grade fever with tachycardia
- Hepatomegaly; with hepatic tenderness
- Symptoms of withdrawal in alcohol-dependent individuals
- Splenomegaly and ascites may be present.
- Chronic and persistent course leads to alcohol-related cirrhosis.
Hepatic fibrosis and sclerosis
- See “Symptoms/Clinical findings” in the learning card on .
- AST (aspartate aminotransferase) > ALT (alanine aminotransferase) (both ↑ ALT and ↑ AST)
- ↑ GGT
- ↑ Serum ferritin
- Macrocytic anemia
↑ CDT(carbohydrate-deficient transferrin)
- Most specific biomarker of heavy alcohol use regardless of the presence of liver disease
- Levels elevated up to 6 weeks after abuse
Imaging and laboratory studies in the case of alcoholic fatty liver will show a reversal of changes within a month if the patient abstains from alcohol!
- > 1 (↑ AST while ALT is normal or only mildly elevated)
- ↑ Alkaline phosphatase (ALP)
- ↑ GGT
- Impaired liver function
- Macrocytic anemia, thrombocytosis , and absolute neutrophilic leukocytosis may be present.
- ↑ Glutamate dehydrogenase (GLDH)
- ↑ Ammonia
- ↑ Uric acid
Hepatic fibrosis and sclerosis
- See .
- Diagnosis confirmed by biopsy
- Alcoholic fatty liver
- Fatty liver with hydropic swelling and ballooning degeneration of hepatocytes within the lobules
- Hepatocyte necrosis within lobules: damaged hepatocytes contain typical intracellular twisted rope-like hyaline inclusions ("Mallory bodies")
- Immunoreactions: increasing number of inflamed infiltrations with neutrophil granulocytes
Fibrosis: pronounced excess formation of fibrous collagenous connective tissue with picture of "chicken wire-like network" in perivenous zones
- Mechanical obstruction of the bile ducts → bile duct proliferates in connective tissue
- Alcohol-related cirrhosis
- Definition: non-alcohol related accumulation of fat in the liver cells with risk of inflammation and cirrhosis
- Very widespread (affects 20–30% of the American adult population)
- Often asymptomatic
- May progress to cirrhosis
A distinction between alcoholic and non-alcoholic fatty liver disease can only be drawn based on the patient history!
The differential diagnoses listed here are not exhaustive.
Mainly characterized by a constellation of clinical features resulting from decreased hepatic function:
Other organ damage following chronic alcohol use
We list the most important complications. The selection is not exhaustive.