What are the symptoms of hepatitis B?

Symptoms of Hepatitis B

Hepatitis B presents with a wide spectrum of clinical manifestations that vary dramatically by age and disease phase, ranging from completely asymptomatic infection (especially in infants and young children) to acute symptomatic hepatitis with jaundice, to chronic liver disease that remains silent until cirrhosis or liver cancer develops.

Acute Hepatitis B Symptoms

Age-Related Symptom Patterns

• Infants, children under 5 years, and immunosuppressed adults are typically asymptomatic when newly infected with hepatitis B 1
• Only 30-50% of persons over age 5 years develop clinical signs or symptoms of acute disease after infection 1

Classic Acute Symptom Presentation

When symptomatic acute disease occurs (typically 2-3 months after exposure, range 6 weeks to 6 months), patients experience 1:

• Fatigue (often the earliest and most prominent symptom)
• Poor appetite/anorexia
• Nausea and vomiting
• Abdominal pain
• Low-grade fever
• Jaundice (yellowing of skin and eyes)
• Dark urine (often one of the first symptoms prompting medical attention)
• Light-colored/clay-colored stools

Physical Examination Findings

Clinical signs on examination include 1, 2:

• Jaundice (visible yellowing)
• Liver tenderness
• Hepatomegaly (enlarged liver)
• Splenomegaly (enlarged spleen, less common)

Temporal Pattern of Acute Symptoms

• Fatigue and loss of appetite typically precede jaundice by 1-2 weeks 1
• Acute illness typically lasts 2-4 months 1
• The case-fatality rate is approximately 1%, with highest rates in adults over 60 years 1

Chronic Hepatitis B Symptoms

The Silent Nature of Chronic Infection

The most critical clinical feature of chronic hepatitis B is that most patients remain asymptomatic for years or decades 1:

• Persons with chronic HBV infection can be completely asymptomatic and have no evidence of liver disease 1
• The majority of chronically infected patients remain asymptomatic until onset of cirrhosis or end-stage liver disease 1
• This silent progression is why chronic infection is responsible for the majority of HBV-related morbidity and mortality 1

Spectrum of Chronic Disease

When chronic hepatitis B does cause symptoms, patients can have 1:

• A spectrum ranging from chronic hepatitis to cirrhosis to liver cancer
• Approximately 25% of persons infected as infants/young children and 15% infected at older ages eventually die of cirrhosis or liver cancer 1

Extrahepatic Manifestations

Potential complications outside the liver include 1:

• Polyarteritis nodosa (blood vessel inflammation)
• Membranous glomerulonephritis (kidney disease)
• Membranoproliferative glomerulonephritis

Critical Clinical Pitfalls

The Asymptomatic Trap

The most dangerous aspect of hepatitis B is that the highest-risk patients—those infected as infants who have >90% chance of chronic infection—are almost always asymptomatic at the time of infection 1. This means:

• You cannot rely on symptoms to identify chronic hepatitis B
• Screening based on risk factors (birth in endemic regions, injection drug use, men who have sex with men) is essential 1
• By the time symptoms appear in chronic infection, significant liver damage may already be present

Age-Inverse Relationship

There is a critical inverse relationship between age at infection and both symptom development and chronicity risk 1:

• Infants: >90% become chronically infected, almost always asymptomatic
• Children 1-5 years: 25-50% become chronically infected, usually asymptomatic
• Older children/adults: <5% become chronically infected, 30-50% symptomatic when acute

Reactivation in Immunosuppressed Patients

Patients with resolved infection who become immunosuppressed can experience reactivation with symptoms of acute illness, though this is rare 1. This is particularly important for patients undergoing chemotherapy or immunosuppressive medication.