Acute liver disease is the severe deterioration of hepatic function secondary to liver conditions such as hepatitis, cirrhosis, or overdose of acetaminophen and other drugs. In the United States, the predominant cause is drug toxicity, while viral hepatitis is the main etiology in developing regions. It occurs in less than 10 cases per million annually in developed countries. Also, most cases occur in adults in their 30s without previous liver disorders.
The potentially fatal condition is classified as fulminant or subfulminant in accordance to the interval between the onset of symptoms and development of encephalopathy . Furthermore, acute liver failure results in coagulopathy, altered mental status, and dysfunction of multiple organs and systems  .
The diagnosis is determined through a history, physical, exam, and extensive laboratory testing. Since there are dangerous manifestations, it is important to assess the full clinical picture during the workup.
The initial goal of therapy involves the identification and treatment of the underlying cause. Since acute liver failure is associated with a high mortality rate, these critically ill patients warrant close monitoring. Specifically, there are crucial aspects to consider such as airway protection, maintenance of the hemodynamic and metabolic status, and prompt recognition of complications such as infection, cerebral edema, and gastrointestinal (GI) bleeding.
Acute liver failure is more prevalent in developing countries, since hepatitis A, B, and E are leading causes of the condition and they are not particularly prevalent in the industrialized world. However, drug-induced liver damage due to acetaminophen and idiosyncratic drug reactions is the predominant cause of acute liver failure in the United States and Western Europe. In these latter countries, vaccinations and good sanitation practice have resulted in the decline of viral hepatitis infections.
Primary cardiac or respiratory failure in ill patients can cause ischemic hepatocellular injury, a potential consequence of severe sepsis. This is accompanied by increased serum aminotransferase concentrations  .
In the United States, the incidence of fulminant liver failure is approximately 2000 cases per year. In acute liver failure, drug-induced hepatotoxicity is responsible for more than half of all cases. Specifically, acetaminophen accounts for 42% of these cases while idiosyncratic drug reactions comprise 12%.
The occurrence of liver failure is observed in all races. Furthermore, a research study in the United States demonstrated that a large percentage was composed of Caucasian people (74%).
Autoimmune liver disease shows a gender preference towards women.
As for age, individuals above 40 years old are associated with a worse prognosis.
The clinical picture of fulminant hepatic failure resembles that of sepsis, which is a state of reduced systemic vascular resistance. The resultant low blood supply to the organs causes further complications. Hence, acute liver failure affects numerous organs and systems.
Brain involvement includes cerebral edema, which is the predominant cause of morbidity and fatality in acute liver failure   . Cerebral edema is probably a consequence of cytotoxic and vasogenic effects. Additionally, increased cerebral perfusion occurs secondarily to cerebral dysregulation, which is a consequence of elevated levels of the vasodilator, nitric oxide.
Coagulopathy commonly occurs secondarily to the decreased synthesis of the coagulation factors in the liver.
Hepatic metabolism of acetaminophen produces a metabolite more toxic than the drug itself.
Some of the main features of acute liver failure include hyperbilirubinemia, which usually manifests at initial presentation.
Hypoglycemia develops as a result of impaired glycogen production and gluconeogenesis.
There are factors that can provide predictive insight regarding the prognosis. For example, worse prognosis is associated with: 1) Severe encephalopathy such as with stage 3 or 4, 2) Patient age younger than 10 years, or greater than 40 years old, 3) Prolonged prothrombin time (PT), and 4) etiology such as idiosyncratic drug reactions or Wilson disease.
The mortality rate of fulminant hepatic failure was higher than 80%, but orthotopic liver transplantation (OLT) has improved survival.
Acute liver failure comprises of two types: fulminant liver failure and subfulminant liver failure. The former is defined as the occurrence of encephalopathy within 8 weeks of onset of symptoms (in patients without pre-existing liver disease). Subfulminant liver failure is characterized by a longer duration between symptoms and encephalopathy.
The clinical picture features a deterioration in mental status, bleeding, purpura, jaundice, and ascites. Nonspecific symptoms include anorexia, malaise, and motor abnormalities. Additionally, fulminant hepatic failure can feature hematemesis or melena due to GI bleeding. A common condition known as fetor hepaticus, which is sweet breath odor, is also a common sign.
Sequelae of acute liver failure include cerebral edema, seizures, metabolic dysfunction, infection, kidney failure, and hemorrhage. Also, in cases with rapid onset of ascites and abdominal pain, this may indicate hepatic vein thrombosis or Budd-Chiari syndrome.
Findings may include right upper quadrant tenderness, smaller liver span, and jaundice. Stigmata associated with chronic liver disease are also common.
Vital signs may show tachycardia, hypotension, and tachypnea whether in the setting of sepsis or not. Also, patients with cerebral edema exhibit papilledema, bradycardia, and hypertension secondary to elevated intracranial pressure (ICP). These individuals may progress to states such as obtundation or coma.
Individuals with jaundice, bleeding, or alteration in mental status should be suspected of having liver failure. When evaluating a patient for acute liver failure, it is crucial to determine the etiology as the therapy and management depend on the underlying cause. The clinician should ascertain all medications ingested by the patient including prescription and over-the-counter drugs and supplements. The workup further consists of a physical exam and laboratory tests.
Since acute liver failure may result in multisystem dysfunction, the following studies should be obtained: a complete blood count (CBC), complete metabolic panel (CMP), renal and liver function tests, PT and international normalized ratio (INR), and urinalysis. Upon confirmation of the diagnosis, crucial tests include an arterial blood gas (ABG), amylase, lipase, blood type and screening. Moreover, if an infection in suspected, blood, urine, and ascitic fluid cultures are indicated.
The findings of the above studies will determine the severity of acute liver disease and the overall clinical picture. Moreover, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) are profoundly increased indicating hepatocellular necrosis. Additionally, PT is prolonged and INR is greater than 1.5.
Also, plasma bilirubin levels are elevated and continue to increase as the disease progresses. In fact, a level above 4 mg/dL is associated with a poor prognosis in acetaminophen toxicity.
An ABG will reveal any acid-base disturbance. Another serious finding, severe hypoglycemia, may develop secondary to impairment in gluconeogenesis and glycogen production.
In patients with both altered mental status and coagulopathy, a head CT scan is performed to identify any intracranial bleeding.
Due to the life-threatening nature of the disease, intensive care is paramount    . When encephalopathy progresses, securing the airway is the top priority. Additionally, the medical team should remain vigilant about the hemodynamics, metabolic function, and nutritional status. Furthermore, early recognition of complications such as GI bleeding and cerebral edema is very important.
Intubation may be necessary for encephalopathic patients. Close monitoring is critical especially in those with worsening mental status. The medical team should be cautious when choosing drugs for intubation and agitation since many cause sedation and make it challenging to monitor the patient's mental status.
Hemodynamic and metabolic management
The therapeutic approach targets hemodynamic and metabolic stability as it is for all critically ill patients. Of importance, fluid replacement for hypotension should be given carefully since these patients are at risk for cerebral swelling. In refractory cases, 20 mL/kg of crystalloid is used. In extreme conditions, vasopressors may be necessary.
Acute liver disease is associated with protein breakdown, and therefore, protein should be replaced carefully. Less protein is administered in patients with hyperammonemia or intracranial hypertension.
CBC, CMP, and coagulation panel should be obtained frequently while LFTs and serum bilirubin are performed daily.
Empiric antibiotics are initiated when the patient demonstrates signs of infection including fever and worsening of hemodynamics, renal function, or mental status. When the cultures' results are obtained, the medications can be altered. If an infection is ruled out, then the antibiotics are discontinued.
In cases with bleeding or severe coagulopathy, fresh frozen plasma (FFP) is important. However, this product can cause volume overload and accentuate cerebral edema. Moreover, use of FFP prohibits the monitoring of PT, which is a value predictive of poor prognosis.
Acetaminophen poisoning can be challenging to diagnose but should be suspected in cases with not clear etiology. It is treated with N-acetylcysteine.
The ultimate treatment of liver failure is liver transplantation. It is correlated with 1-year survival rate of almost 80%. Hence, it is reserved for those with a prognosis that is worse without a liver transplant.
Lactulose can be beneficial in patients with encephalopathy. As for seizures, phenytoin is a good choice.
Acute liver failure is associated with numerous etiologies. One of the causes, acetaminophen overdose, can be prevented if the dosage guidelines are followed correctly. The same applies to all medications and supplements as well. Additionally, depending on the type of viral hepatitis, an infection can be prevented through vaccinations, implementation of good hygiene, and practicing a safe and healthy lifestyle.
Acute liver failure is a disease in which there is a rapid decline in the perfomance of the liver. It can be caused by liver disease, viral hepatitis, especially hepatitis B, cirrhosis, or poisoning due to alcohol or medications. In fact, acetaminohen overdose is the most common cause of acute liver failure in the United States, whereas viral hepaitis is the most common cause in the developing world.
When the liver becomes largely damaged, failure occurs. It can occur over days, weeks, months or years.
The liver is responsible for many functions. So when it becomes damaged, there are many detrimental consequences such as:
Acute liver disease is diagnosed through the history, physical exam, and important blood tests that check for liver function, electrolytes, liver proteins, and others.
As soon as it is diagnosed, liver failure is treated promptly to prevent further complications. These patients are admitted to the intensive care unit (ICU).
Treatment consists of the following: