Liver failure

Liver failure is a severe deterioration of the liver that cause a progressive decline in liver function.

Liver failure occurs when a large portion of the liver is irreparably damaged and the liver cannot perform its functions in a proper way.

Liver failure may be classified into:

• Acute: Rapid development (days to weeks).
• Chronic: Progressive development (months to years).
• Acute on chronic: Some patients with a well-compensated chronic disease suddenly develop an acute liver failure.

Acute liver failure progresses rapidly and may cause systemic multiorgan failure, altered mental status, renal failure, pulmonary failure and infections.

Acute liver failure usually produces encephalopathy within 6 months. When the encephalopathy develops within 2 weeks of the onset, it is called fulminant liver failure.

Causes

The most common causes of acute liver failure are:

• Deliberate or accidental ingestion of acetaminophen (paracetamol)
• Autoimmune hepatitis
• Hepatitis A
• Hepatitis B
• Hepatitis E
• Wilson disease
• Other drugs (isoniazid, propylthiouracil, phenytoin, valproate, etc.)

Symptoms

The main symptoms are:

• Nausea and vomiting
• Fatigue
• Jaundice (yellow discoloration of the skin and the mucous membranes)
• Ascites (abnormal build-up of fluid in the abdomen)
• Easy bruising and bleeding
• Portal hypertension

Diagnostic

In a blood test, transaminase levels (AST and ALT) are elevated into the thousands and may later decline. Bilirubin level will rise progressively and the prothrombin time will be prolonged.

A liver biopsy may be helpful in the diagnosis.

Treatment

If the underlying cause is an overdose of acetaminophen (paracetamol), the treatment requires the urgent administration of N-acetylcysteine (NAC). If the liver failure is due to other reason, it is necessary to find the cause to apply a specific treatment. In many cases, liver transplantation is the only effective therapy.

Prognosis

Acute liver failure has a poor prognosis because there is a high probability that it progresses to a multiorgan failure with fatal consequences.

Chronic liver failure is a progressive deterioration of the liver functions for more than 6 months. It usually leads to liver fibrosis or cirrhosis. Therefore, cirrhosis is usually the end stage of chronic liver failure.

Causes

The most common causes of chronic liver failure are:

• Alcoholism
• Fatty liver
• Viral hepatitis: Hepatitis C, hepatitis B
• Biliary diseases: Primary biliary cholangitis, primary sclerosing cholangitis
• Metabolic diseases: Hemochromatosis (iron overload), Wilson disease, alpha 1 antitrypsin deficiency
• Drug induced: Methotrexate, amiodarone, nitrofurantoin, phenytoin, isoniazid, etc.

Symptoms

About 40% of people with chronic liver failure are asymptomatic. If symptoms are present, the most common are:

• Weight loss
• Weakness
• Jaundice (yellow discoloration of the skin and mucous membranes)
• Portal hypertension
• Itching

Diagnostic

In a blood test, transaminase levels (AST and ALT) are 2 or 3 times over the normal ranges. Bilirubin and ALP (alkaline phosphatase) will be above the normal range. Albumin, by contrast, will be low.

Ultrasound or a liver biopsy may help in the diagnosis.

Treatment

The ultimate goal of the treatment is to stop the progression of the disease. Therefore, the treatment should be focused on the underlying cause. When there is no other alternative, a liver transplant may be necessary.

Complications

Chronic liver failure may lead, in addition to cirrhosis, to severe complications such as encephalopathy, hepatorenal syndrome or hepatopulmonary syndrome. Besides, chronic liver failure increases the risk of suffering from liver carcinoma.

Some patients after years of suffering stable chronic disease suddenly develop signs of acute liver failure. It happens often in patients with established cirrhosis. The prognosis is poor because the short-term mortality is around 50%.