A.29 Acute Hepatic Failure. Fulminant Hepatic Failure

Question 1

A.29 Acute Hepatic Failure. Fulminant Hepatic Failure

Acute Hepatic Failure

Answer 1

Acute liver failure (ALF) is a severe condition characterized by rapidly progressive liver injury, hepatic encephalopathy, and impaired synthetic function, which results in coagulopathy. The most common causes are infections (e.g., viral hepatitis) and acetaminophen toxicity.

Question 2

A.29 Acute Hepatic Failure. Fulminant Hepatic Failure
Etiology

Acute Hepatic Failure

Answer 2

Idiopathic (20–45% of cases)
Hepatotoxic drugs and supplements: Acetaminophen toxicity (most common cause in the US) [9]
Infection
Acute viral hepatitis
- HAV infection, HBV infection, or HEV infection
- HBV-HDV coinfection or superinfection
Toxoplasmosis (e.g., in transplant recipients)
Other exogenous toxins: mushroom poisoning, aflatoxin, alcohol
Metabolic Disorders (e.g., Wilson’s disease)

Question 3

A.29 Acute Hepatic Failure. Fulminant Hepatic Failure
Hepatitis E

Acute Hepatic Failure

Answer 3

Caused by the hepatitis E virus (HEV), part of the Hepeviridae family; small, non-enveloped virus with positive-sense RNA.
Route of Transmission: fecal-oral.
Incubation period: 2–8 weeks.
Clinical features typically align with those of hepatitis A.
The disease is usually self-limiting, but it can cause fulminant hepatitis, especially in pregnant women.

Question 4

A.29 Acute Hepatic Failure. Fulminant Hepatic Failure
Clinical features

Acute Hepatic Failure

Answer 4

Presentation is mostly nonspecific; clinicians should maintain a high index of suspicion in patients who acutely develop the following symptoms:
* Signs of hepatic encephalopathy (e.g., altered level of consciousness, asterixis)
* Symptoms of cerebral edema
* Nausea, vomiting
* Fatigue, lethargy, malaise
* Jaundice, pruritus
* Anorexia

Question 5

A.29 Acute Hepatic Failure. Fulminant Hepatic Failure
Treatment:

Acute Hepatic Failure

Answer 5

Supportive care is the primary approach; no vaccine is available.
If indicated, start NAC as early as possible.
If the underlying cause is known, initiate specific management.
Assess candidacy for liver transplantation and, if necessary, transfer candidates to a transplant center without delay.
Manage any complications, e.g., cerebral edema, acute kidney injury, or coagulopathy.

Question 6

A.29 Acute Hepatic Failure. Fulminant Hepatic Failure
Diagnosis:

Acute Hepatic Failure

Answer 6

Obtain initial laboratory studies to support the diagnosis and assess severity based on organ dysfunction.
ALF is confirmed if all of the following are present:

Encephalopathy
Abnormal liver chemistries
Coagulopathy (INR > 1.5)

Obtain imaging to rule out alternative diagnoses, e.g., head CT to rule out other causes of encephalopathy.

Liver biopsy may be considered if the underlying cause remains unclear.

Question 7

A.29 Acute Hepatic Failure. Fulminant Hepatic Failure
Laboratory studies

Acute Hepatic Failure

Answer 7

CMP
* Liver chemistries: elevated transaminases, hyperbilirubinemia
* Hypoglycemia
* Electrolytes: may show various disturbances.
* Renal function tests: ↑ BUN and creatinine in patients with acute kidney injury or hepatorenal syndrome
Coagulation panel
* Prolonged prothrombin time (INR ≥ 1.5)
* Presence of other derangements (e.g., hypofibrinogenemia) is variable
CBC
* Platelet count typically ≤ 150,000/mm3
Blood gas analysis
* Acid-base status can vary between acidosis
, mixed acid-base disorder, and alkalosis
, depending on the underlying etiology [15]
* Lactate: commonly elevated; marker of severe disease

Question 8

A.29 Acute Hepatic Failure. Fulminant Hepatic Failure

Acute Hepatic Failure

Answer 8

Rapidly worsening liver function resulting in coagulopathy and hepatic encephalopathy.
Fulminant liver failure: onset of hepatic encephalopathy within 8 weeks of initial symptoms.
Subacute liver failure: onset occurs within 26 weeks.

Question 9

A.29 Acute Hepatic Failure. Fulminant Hepatic Failure
Etiology:

Fulminant Hepatic Failure

Answer 9

Drugs:
- Acetaminophen
- Halothane
- Isoniazid
- Amanita phalloides (mushroom poisoning)
- Alprazolam
- Alcohol: Chronic use
Viral Factors:
- Hepatitis viruses (A, B, E, or co-infections with D, C, or cytomegalovirus)
Other Causes:
- Autoimmune hepatitis, Wilson’s disease, and other conditions.

Question 10

A.29 Acute Hepatic Failure. Fulminant Hepatic Failure
Clinical Features:

Fulminant Hepatic Failure

Answer 10

Signs of hepatic encephalopathy include:
Altered mental state: nausea, vomiting, confusion

Question 11

A.29 Acute Hepatic Failure. Fulminant Hepatic Failure
Diagnostics:

Fulminant Hepatic Failure

Answer 11

Laboratory findings include:
PT (Prothrombin Time): markedly elevated
ALT (Alanine Aminotransferase), AST (Aspartate Aminotransferase), and bilirubin levels often exceed 150,000.
Serum electrolytes should be monitored.
Toxicology screening (e.g., acetaminophen level).
RUQ (right upper quadrant) ultrasound.

Question 12

A.29 Acute Hepatic Failure. Fulminant Hepatic Failure
Treatment:

Fulminant Hepatic Failure

Answer 12

Prompt Referral: Immediate transfer to a liver transplant center.
Medication: Administer IV N-acetylcysteine.
Management of Complications: Address issues such as cerebral edema, encephalopathy, coagulopathy, renal failure, and infection.
Underlying Causes: Treat the root cause, which may include antiviral therapy for hepatitis B, corticosteroids for autoimmune hepatitis, or delivery for HELLP syndrome.
Liver Transplantation: The only viable treatment option for patients lacking adequate regeneration of hepatocytes.

The mortality rate for patients without liver transplantation varies between 30% (in cases of acetaminophen toxicity) and 80% (in non-acetaminophen-related liver failure).