Acute liver failure, also known as fulminant hepatic failure, is loss of liver function that occurs rapidly in days or weeks, usually in a person who has no pre-existing liver disease.
Acute liver failure is less common than chronic liver failure, which develops more slowly.
Acute liver failure can cause serious complications, including excessive bleeding and increasing pressure in the brain. It's a medical emergency that requires hospitalization.
Causes
Acute liver failure occurs when liver cells are damaged significantly and are no longer able to function. Potential causes include:
- Acetaminophen overdose. Taking too much acetaminophen (Tylenol, others) is the most common cause of acute liver failure in the United States. Acute liver failure can occur after one very large dose of acetaminophen, or after higher than recommended doses every day for several days.
If you suspect that you or someone you know has taken an overdose of acetaminophen, seek medical attention as quickly as possible. Do not wait for the signs of liver failure.
- Prescription medications. Some prescription medications, including antibiotics, nonsteroidal anti-inflammatory drugs and anticonvulsants, can cause acute liver failure.
- Herbal supplements. Herbal drugs and supplements, including kava, ephedra, skullcap and pennyroyal, have been linked to acute liver failure.
- Hepatitis and other viruses. Hepatitis A, hepatitis B and hepatitis E can cause acute liver failure. Other viruses that can cause acute liver failure include Epstein-Barr virus, cytomegalovirus and herpes simplex virus.
- Toxins. Toxins that can cause acute liver failure include the poisonous wild mushroom Amanita phalloides, which is sometimes mistaken for edible species.
- Autoimmune disease. Liver failure can be caused by autoimmune hepatitis — a disease in which your immune system attacks liver cells, causing inflammation and injury.
- Diseases of the veins in the liver. Vascular diseases, such as Budd-Chiari syndrome, can cause blockages in the veins of the liver, leading to acute liver failure.
- Metabolic disease. Rare metabolic diseases, such as Wilson's disease and acute fatty liver of pregnancy, infrequently cause acute liver failure.
- Cancer. Cancer that either begins in or spreads to your liver can cause your liver to fail.
- Many cases of acute liver failure have no apparent cause.
Symptoms
Acute liver failure is a broad term that encompasses both fulminant hepatic failure and subfulminant hepatic failure (or late-onset hepatic failure). Fulminant hepatic failure is generally used to describe the development of encephalopathy within 8 weeks of the onset of symptoms in a patient with a previously healthy liver. Subfulminant hepatic failure is reserved for patients with liver disease for up to 26 weeks before the development of hepatic encephalopathy.
Signs and symptoms of acute failure may include the following:
- Encephalopathy
- Cerebral edema: May lead to signs of increased intracranial pressure (ICP) (eg, papilledema, hypertension, bradycardia)
- Jaundice: Often present but not always
- Ascites: Potential for hepatic vein thrombosis with rapid development in the presence of fulminant hepatic failure accompanied by abdominal pain
- Right upper quadrant tenderness: Variably present
- Change in liver span: May be small due to hepatic necrosis or may be enlarged due to heart failure, viral hepatitis, or Budd-Chiari syndrome
- Hematemesis or melena: Due to upper gastrointestinal (GI) bleeding
- Hypotension and tachycardia: Due to reduced systemic vascular resistance
Complications
Acute liver failure often causes complications, including:
- Excessive fluid in the brain (cerebral edema). Excessive fluid causes pressure to build in your brain, which can displace brain tissue outside of the space it normally occupies (herniation). Cerebral edema can also deprive your brain of oxygen.
- Bleeding and bleeding disorders. A failing liver isn't able to produce sufficient amounts of clotting factors, which help blood to clot. People with acute liver failure often develop bleeding from the gastrointestinal tract. Bleeding may be difficult to control.
- Infections. People with acute liver failure are at an increased risk of developing a variety of infections, particularly in the blood and in the respiratory and urinary tracts.
- Kidney failure. Kidney failure often occurs following liver failure, especially in cases of acetaminophen overdose, which damages both your liver and your kidneys.
Diagnosis
The most important step in the assessment of patients with acute liver failure is to identify the cause, because certain conditions necessitate immediate and specific treatment and affect prognosis. All patients with clinical or laboratory evidence of moderate or severe acute hepatitis should have immediate measurement of prothrombin time (PT) and careful evaluation of mental status. PT prolongation or mental status changes is grounds for hospital admission.
Laboratory testing
- Complete blood count: May reveal thrombocytopenia
- Coagulation studies: PT and/or international normalized ratio (INR)
- Liver function tests: Often elevated levels of aspartate aminotransferase (AST)/serum glutamic-oxaloacetic transaminase (SGOT), alanine aminotransferase (ALT)/serum glutamic-pyruvic transaminase (SGPT), alkaline phosphatase (ALP)
- Serum bilirubin level: Elevated
- Serum ammonia level: May be dramatically elevated (accuracy: arterial > venous level)
- Serum glucose level: May be dangerously low
- Serum (arterial) lactate level: Often elevated
- Arterial blood gas: May reveal hypoxemia
- Serum creatinine level: May be elevated
- Serum free copper and ceruloplasmin levels: Low levels with Wilson disease
- Serum phosphate level: May be low
- Acetaminophen and acetaminophen-protein adducts levels
- Drug screening: Consider in patients who are intravenous drug abusers
- Blood cultures: For patients with suspected infection
- Viral serologies: Consider for hepatitis A virus immunoglobulin M (IgM), hepatitis B surface antigen (HBsAg), hepatitis B virus anticore IgM; hepatitis C viral load testing; hepatitis D virus IgM if HBsAg is positive; in posttransplantation or immunosuppressed setting, consider studies for cytomegalovirus viremia, cytomegalovirus antigenemia, and herpes simplex virus
- Autoimmune markers (for autoimmune hepatitis diagnosis): Antinuclear antibody (ANA), anti-smooth muscle antibody (ASMA), and immunoglobulin levels
Other studies may include the following:
- Electroencephalography
- Intracranial pressure monitoring
- Percutaneous (contraindicated in presence of coagulopathy) or transjugular liver biopsy
- Imaging studies
Hepatic Doppler ultrasonography
- Abdominal computed tomography (CT) scanning or magnetic resonance imaging without contrast
- Cranial CT scanning
Treatment
People with acute liver failure are often treated in the intensive care unit of a hospital —and when possible, in a facility that can perform a liver transplant if necessary. Your doctor may try to treat the liver damage itself, but in many cases, treatment involves controlling complications and giving your liver time to heal.
Treatments for acute liver failure
Acute liver failure treatments may include:
- Medications to reverse poisoning. Acute liver failure caused by acetaminophen overdose or mushroom poisoning is treated with drugs that can reverse the effects of the toxin and may reduce liver damage.
- Liver transplant. When acute liver failure can't be reversed, the only treatment may be a liver transplant. During a liver transplant, a surgeon removes your damaged liver and replaces it with a healthy liver from a donor.
Treatments for complications
Your doctor will work to control signs and symptoms you're experiencing and try to prevent complications caused by acute liver failure. This care may include:
- Relieving pressure caused by excess fluid in the brain. Cerebral edema caused by acute liver failure can increase pressure on your brain. Medications can help reduce the fluid buildup in your brain.
- Screening for infections. Your medical team will take periodic samples of your blood and urine to be tested for infection. If your doctor suspects that you have an infection, you'll receive medications to treat the infection.
- Preventing severe bleeding. Your doctor can give you medications to reduce the risk of bleeding. If you lose a lot of blood, your doctor may perform tests to find the source of the blood loss, and you may require blood transfusions.
Prevention
Reduce your risk of acute liver failure by taking care of your liver.
- Follow instructions on medications. If you take acetaminophen or other medications, check the package insert for the recommended dosage, and don't take more than that.
- Tell your doctor about all your medicines. Even over-the-counter and herbal medicines can interfere with prescription drugs you're taking.
- Drink alcohol in moderation, if at all. Limit the amount of alcohol you drink to no more than one drink a day for women of all ages and men older than 65 and no more than two drinks a day for younger men.
- Avoid risky behavior. Get help if you use illicit intravenous drugs. Don't share needles. Use condoms during sex. If you get tattoos or body piercings, make sure the shop you choose is clean and safe. Don't smoke.
- Get vaccinated. If you're at increased risk of contracting hepatitis, if you've been infected with any form of the hepatitis virus or if you have chronic liver disease, talk to your doctor about getting the hepatitis B vaccine. A vaccine is also available for hepatitis A.
- Avoid contact with other people's blood and body fluids. Accidental needle sticks or improper cleanup of blood or body fluids can spread hepatitis viruses. Sharing razor blades or toothbrushes can also spread infection.
- Don't eat wild mushrooms. It can be difficult to distinguish an edible mushroom from a poisonous one.
- Take care with aerosol sprays. When you use an aerosol cleaner, make sure the room is ventilated, or wear a mask. Take similar protective measures when spraying insecticides, fungicides, paint and other toxic chemicals. Follow manufacturers' instructions.
- Watch what gets on your skin. When using insecticides and other toxic chemicals, cover your skin with gloves, long sleeves, a hat and a mask.
- Maintain a healthy weight. Obesity can cause a condition called nonalcoholic fatty liver disease, which may include fatty liver, hepatitis and cirrhosis.
Prognosis
Historically mortality has been unacceptably high, being in excess of 80%. In recent years the advent of liver transplantation and multidisciplinary intensive care support have improved survival significantly. At present overall short term survival with transplant is more than 65%.
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