What is hepatitis?

Hepatitis: Types, Clinical Features, and Management

Hepatitis is an inflammatory condition of the liver characterized by liver cell injury and necrosis, which can be caused by viral infections, autoimmune disorders, or other factors affecting liver function. 1

Types of Hepatitis

Viral Hepatitis

• Hepatitis A (HAV): Transmitted through the fecal-oral route, causing acute infection without chronic disease 1, 2
• Hepatitis B (HBV): A DNA virus transmitted through blood, sexual contact, and perinatally; can cause both acute and chronic infection 1, 3
• Hepatitis C (HCV): A bloodborne RNA virus with high rates of chronicity that differs from HBV in structure and treatment approach 3
• Hepatitis D (HDV): Requires HBV coinfection to replicate 4
• Hepatitis E (HEV): Causes epidemic non-A, non-B hepatitis 4

Non-Viral Hepatitis

• Autoimmune Hepatitis: Characterized by interface hepatitis, hypergammaglobulinemia, and autoantibodies 1, 5
• Alcoholic Hepatitis: Caused by excessive alcohol consumption 6
• Drug-Induced Hepatitis: Can be caused by medications like minocycline, nitrofurantoin, and isoniazid 1

Clinical Presentation

Hepatitis A

• Children: >90% of infections are asymptomatic in children under 6 years 2
• Adults: Typically symptomatic with jaundice occurring in >70% of patients 2, 7
• Incubation period: Average 28 days (range: 15-50 days) 2
• Initial symptoms: 1-7 day prodromal illness with anorexia, malaise, fever, and nausea 2
• Progression: Dark urine often appears first, followed by clay-colored stool and jaundice 2, 7

Hepatitis B

• Acute infection: Develops in 30-50% of adults with initial infection, characterized by anorexia, nausea, vomiting, and often jaundice 1
• Risk of chronicity: Varies by age - 2-6% in adults, 30-90% in infants and young children 1, 3
• Chronic carriers: May be asymptomatic despite high levels of viral replication 1

Autoimmune Hepatitis

• Presentation: Can be acute, insidious, or asymptomatic 1, 5
• Diagnostic features: Interface hepatitis on biopsy, portal plasma cell infiltration, elevated immunoglobulins, and presence of autoantibodies 1

Hepatic Encephalopathy

• Definition: Brain dysfunction caused by liver insufficiency and/or portosystemic shunting 1
• Manifestations: Ranges from subclinical alterations to coma 1
• Prevalence: Occurs in 30-40% of cirrhosis patients at some point in their clinical course 1

Diagnosis

Viral Hepatitis

• HAV: Detection of IgM anti-HAV, which becomes detectable 5-10 days before symptom onset 2, 7
• HBV: Serological markers including HBsAg, anti-HBc, anti-HBs, HBeAg, anti-HBe, and HBV DNA 3
• Clinical differentiation: Viral hepatitis types cannot be differentiated based on clinical features alone 2

Autoimmune Hepatitis

• Diagnostic criteria: Presence of autoantibodies (ANA, SMA, anti-LKM1), elevated immunoglobulin G, and interface hepatitis on biopsy 1
• Exclusion diagnosis: Requires ruling out viral hepatitis, drug-induced liver injury, Wilson disease, and other conditions 1, 5

Complications

Acute Complications

• HAV: Relapsing disease in 10-15% of patients; fulminant hepatitis is rare (0.3-0.6% case fatality) 2
• Hepatic encephalopathy: A defining feature of decompensated liver disease 1

Chronic Complications

• HBV: 15-25% lifetime risk of death from chronic liver disease or hepatocellular carcinoma in chronically infected patients 1
• Hepatorenal syndrome: Severe complication of end-stage cirrhosis characterized by functional renal failure 8, 6

Prevention and Management

Prevention

• HAV/HBV: Vaccination available and effective 3, 2
• Screening: Recommended for high-risk groups including persons born in endemic areas, men who have sex with men, injection drug users, dialysis patients, HIV-infected individuals, pregnant women, and contacts of infected persons 1

Treatment

• Viral hepatitis: Treatment varies by type; HBV typically treated with nucleos(t)ide analogues 3
• Autoimmune hepatitis: Corticosteroids and immunomodulatory drugs with almost universal response when promptly administered 1, 5
• Hepatic encephalopathy: Management depends on severity and underlying cause 1

Special Considerations

• Coinfection: In HBV/HCV coinfection, treatment for HCV should be prioritized if HCV RNA is detectable 3
• Liver transplantation: The only curative treatment for hepatorenal syndrome and end-stage liver disease 8, 6
• Monitoring: Regular follow-up is essential for all forms of chronic hepatitis to detect progression and complications early 1, 5