Acute liver failure (ALF) occurs when many cells in the liver die or become very damaged in a short amount of time. This causes the liver to fail to work as it should.

The liver removes toxins from the body, helps maintain blood glucose levels, is a part of the immune system and regulates blood clotting. When the liver fails it is an emergency and needs to be treated immediately.

Causes of Acute Liver Failure

Acute liver failure has many causes. Some causes of acute liver failure are:

• Metabolic conditions (problems with the physical and chemical processes inside the liver that must happen for a person to live)
• Infections/viruses
• Immunological dysfunction
• Cardiovascular conditions (which cause a lack of blood supply to the liver)

Often the cause of acute liver failure in children cannot be found. One study showed that this was the case for about 44% of all children with acute liver failure. This number is about 63% in children with acute liver failure under 2 years of age.

Causes of Acute Liver Failure

In Infants

• Infections: Herpes simplex, echovirus, adenovirus, hepatitis B, parvovirus, others
• Drugs/toxins: Acetaminophen
• Cardiovascular: Extracorporeal membrane oxygenation, hypoplastic left heart syndrome, shock, asphyxia, myocarditis
• Metabolic: Galactosemia, tyrosinemia, iron storage, mitochondrial condition, HFI, fatty acid oxidation, others
• Immune: Autoimmune hepatitis, immune dysregulation, immune deficiency, hemophagocytic lymphohistiocytosis 

In Toddlers and Older Children

• Infections: Hepatitis A, B and D, NANB hepatitis, Epstein-Barr virus, cytomegalovirus, adenovirus, herpes, leptospirosis, others 
• Drugs/toxins: Valproic acid, isoniazid, halothane, acetaminophen, mushroom, phosphorous, aspirin, others
• Cardiovascular: Myocarditis, heart surgery, cardiomyopathy, Budd-Chiari syndrome
• Metabolic: Fatty acid oxidation, Reye's syndrome, leukemia, others
• Immune: Autoimmune hepatitis, immune dysregulation, immune deficiency, hemophagocytic lymphohistiocytosis

Signs and Symptoms of Acute Liver Failure

Symptoms of acute liver failure can be like those of a virus. This can include upset stomach, feeling tired all the time, or throwing up. This can quickly progress to jaundice (yellowing of the skin), encephalopathy and coagulopathy (problem with blood clotting).

In encephalopathy the brain does not work the way it should. This happens when the liver is not able to break down or get rid of toxic products. A liver that is working like it should is able to break down toxins and carry them out of the liver.

Infants may be irritable, have crying spells and can't be made to feel better, or they might want to sleep more during the day than at night.

Older children may seem angry, have a hard time falling asleep, forget things, be confused or feel drowsy.

Diagnosis of Acute Liver Failure

Lab studies and a physical exam can tell if there are signs of a liver problem. These include:

• Signs of mental confusion (encephalopathy)
• Levels of liver enzymes that increase very quickly
• Jaundice (high bilirubin levels)
• Coagulopathy (problem with blood clotting)

If there seems to be a liver problem, the child should be seen by an expert at a liver care/transplant center. The doctor there will figure out if the child’s cause of liver failure can be treated.

Treatment for Acute Liver Failure

Treatment for acute liver failure depends on what caused the disease. Some causes can be treated by medicine and the liver will recover. If the liver does not recover from medication, a liver transplant may be required.

• Supportive care – There are some patients who will get better on their own if they receive treatment for their symptoms. Many patients whose condition is caused by a virus get better on their own. Their liver can reform itself into a healthy organ. 
• Medicine – When the acute liver failure is caused by a cardiovascular condition, the immune system or by acetaminophen, it can sometimes be treated with medicine. Medicine may be able to reverse it if given early enough. Metabolic diseases may be treated with medicine or diet if there has not yet been any damage that cannot be reversed. 
• Treating encephalopathy – Hepatic encephalopathy always develops when liver failure is sudden and severe. It is treated by trying to prevent the production of toxic products in the liver, which cause the condition.
• Treating coagulopathy – Medicines or blood products may be needed if blood clotting problems become unsafe.
• Transplant – About 40% of children with acute liver failure need a liver transplant to survive.

Whether a liver transplant is advised for the child depends on:

• If the cause of liver failure
• If there is disease in more than one organ or part of the body
• If the child has other medical conditions that are not curable
• The amount of brain damage
• The chances that the brain damage could be reversed after the transplant liver is working.

Long-Term Outlook

Acute liver failure in children is rare. The chance the child will recover depends mainly on the cause and their age. The stage of the disease and the amount of brain damage also affect recovery. If the liver heals itself, most often there is a full recovery.

The survival rate for children with acute liver failure who have a liver transplant is as high as 90%