Health Topics

Acute liver failure has many causes. Acetaminophen (such as Tylenol®) is an example of a common medicine that can affect how the liver works. This can occur if a child is given the wrong dosage of the medicine or if too much is taken in a short amount of time.

Acetaminophen hepatotoxicity (damaging to the liver) accounts for 16 percent of childhood acute liver failure cases in the United States and generally occurs in older children.

Other causes of acute liver failure are metabolic conditions (problems related to the physical and chemical processes that occur inside the liver that must happen for a person to live), infections / viruses and cardiovascular conditions (which cause a lack of blood supply to the liver).

Causes of acute liver failure seem to vary based on the age of the child. Infection or metabolic conditions at birth are the most common causes of acute liver failure in children under 2 years old. Hepatitis caused by a virus (such as hepatitis A or B) and drug-induced liver failure, such as acetaminophen hepatotoxicity, are more likely in older children.

However, most of the time the cause of acute liver failure in children cannot be determined. One study showed that this was the case for about 44 percent of all children who were diagnosed with acute liver failure and about 63 percent for 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  

In Toddlers and Older Children

• Infections: Hepatitis A, B and D, NANB hepatitis, Epstein-Barr virus, cytomegalovirus, 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

Symptoms of acute liver failure can be like those of a virus, such as upset stomach (nausea), a tired feeling all the time (fatigue) or vomiting. This can rapidly progress to jaundice (yellowing of the skin) and encephalopathy.

Encephalopathy is a condition in which the brain does not work properly. This happens when the liver is not able to break down or get rid of toxic products in the liver. (A liver that is working properly is able to break down toxins and carry them out of the liver.)

Encephalopathy always occurs when a child has sudden and severe liver failure. Infants up to 28 days old may not have many noticeable signs of encephalopathy, although they will have jaundice symptoms.

Infants older than 28 days 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, be forgetful or confused, or feel drowsy.

Acute liver failure is hard to diagnose early on because it is rare and symptoms look like other illnesses.

Lab studies and a physical exam can tell whether there is evidence of a liver problem. This includes signs of mental confusion (encephalopathy), levels of liver enzymes that increase very quickly, jaundice and 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 determine if the patient's cause of liver failure can be treated.

Treatment for acute liver failure depends on what caused the disease. Some causes are treatable by either medicine or a liver transplant. 

• Supportive care – There are some patients who will get better by themselves if they receive treatment for their symptoms. Many patients whose condition is caused by a virus get better on their own. Their liver is able to reform itself into a healthy organ. 
• Medication – When the acute liver failure is caused by a cardiovascular condition or by acetaminophen, it sometimes can be treated with medicine. Medicine may be able to reverse the condition if given early enough.
  
  Metabolic diseases may be treated with medicine or diet if irreversible damage has not yet occurred. 
• Transplant – Approximately half of all children with acute liver failure need a liver transplant to survive. For the majority of patients whose cause of liver failure is not known, a transplant is the only option.

A doctor will consider several things when recommending or not recommending a liver transplant, including: the cause of the disease if known, likelihood the transplant will be successful, whether there is a disease in more than one organ or part of the body, the amount of brain damage, and the chances that the brain damage could be reversed once the transplanted liver is working.

One of the challenges of liver transplant for patients with acute liver failure is that liver failure happens quickly and it often takes time to obtain an organ for transplant.

If a transplant is the best treatment option, the doctor and the other members of the patient care team will focus on preventing complications and will treat symptoms while waiting for the donated liver.

• Treating encephalopathy – Hepatic encephalopathy always develops when liver failure occurs suddenly and severely. It is treated by trying to prevent the production of toxic products in the liver, which is what cause the condition.

In severe cases of encephalopathy, cerebral edema (brain swelling) can occur. It often requires a device to be placed on the surface of the brain to monitor the swelling and pressures inside the skull.

Treatment includes the use of mannitol, a sugar compound that helps absorb fluid away from the brain, which decreases the pressure.

Acute liver failure in children is a rare disease. The likelihood of recovery depends primarily on the cause of the liver failure and age of the child. The stage of the disease and the amount of brain damage also affect recovery. Remarkably, when the liver heals itself, there usually is a complete recovery.

Infants and children with metabolic disease are less likely to recover since a liver transplant is not an option. The outcome for children with acetaminophen hepatoxicity is good when they are treated promptly with medicine.

The survival rate for children with acute liver failure who have a liver transplant is as high as 90 percent. Most recipients can expect a 70 percent five-year survival.

While the outcome for liver transplantation is generally good, there is a higher risk of having blood and bone marrow complications following liver transplant in a patient with acute liver failure.

Neurologic recovery (mental status) depends on the level of brain damage at the time of transplant. The less damage suffered prior to transplant, the better the chance for recovery.