Hepatitis B

Question 1

Etiology of hepatitis B

Answer 1

Hepatitis B virus DNA

Question 2

Transmission of hepatitis B

Answer 2

Sexually, parentrally , vertical transmission (mother to child)

Question 3

Incubation period for hepatitis B

Answer 3

1-6 months

Question 4

Risk groups for Hepatitis B

Answer 4

• IV drug users
• Individuals whose close contact have chronic HBV infection
• Infants or HBV positive mothers
• Multiple sex partners or sex partners who are HBV positive
• Patients undergoing hemodialysis
• Hep C or HIV positive individuals

Question 5

Clinical features of hepatitis B

Answer 5

• Acute Infection- Infection that was acquired in the past 6 months.
• Serum sickness like syndrome- can develop during prodromal period, 1-2 weeks after infection. Symptoms: Fever, rash and arthralgia
• Subclinical hepatitis (70%) - most common in children under 5 and
  immunocompromised
• Symptomatic hepatitis( 30%); fever, rash arthralgia, myalgia, fatigue, nausea, Jaundice, RUQ pain
• Symptoms usually resolve after a few weeks up to 6 months.
• May develop into fulminant hepatitis (0.5%) which is severe liver injury due to massive necrosis of hepatocytes

Question 6

Chronic hepatitis B infection

Answer 6

Chronic Infection- Infection persisting for more than 6 months with detection HBsAg and possibly symptoms of liver damage.
- Most are inactive and non-contagious carriers
- Potential reactivation of chronic inactive hepatitis may show as asymptomatic, imitate acute hepatitis or result in liver failure
- About 25% of chronic patients develop cirrhosis 10-20%develop extrahepatic manifestations such as polyarteritis nodosa and
membranous glomerulonephritis

Question 7

Hepatitis B diagnosis

Answer 7

HBV surface antigen (HBsAg) correlates with presence of the virus (until the window period)

HBV core antigen (HBcAg) is not detectable in serum;
HBV e antigen (HBeAg) correlates with levels of HBV DNA and indicates significant replication, and is elevated in highly

Determination of
Viral Load:
PCR for HBV DNA
(HBsAg is detectable weeks after HBsAg vaccine
(birth, 1-2 months, 6 months) exposure, prior to symptoms, undetectable 4-6 months after infection clears)
(The window period occurs because HBsAg becomes undetectable as the body is fighting off the virus, while anti-HBsAg IgG is still at relatively low levels)

Additional Tests
● LFT - AST/ALT (increased in acute but variable values in chronic)
● GTP, AP- increased
● Albumin- decreased in case of cirrhosis
● Abdominal USG- decreased echogenicity of liver in acute, but increased in chronic

Question 8

Hepatitis B serology

Answer 8

SEROLOGY
Acute Infection:
HBsAg + anti-HBcAg IgM + HBeAg (first 3 months)

Window Period (around 6-8 months of acute infection):
anti-HBcAg IgM

Chronic Infection:
anti-HBsAg + anti-HBcAg IgG + HBeAg (if severe)

Prior Vaccination:
anti-HBsAg IgG

Prior Infection:
anti-HBsAg IgG + anti-HBcAg IgG

Question 9

Treatment of hepatitis B

Answer 9

• Acute: supportive treatment
• Chronic; anti-virals (Tenofovir, Entecavir, PEG- IFN-alpha) and liver transplantation in case of severe cirrhosis or liver failure.

Question 10

Hepatitis B complications

Answer 10

• Hepatitis D virus infection, Acute liver failure
• Fulminant liver failure; onset of hepatic encephalopathy within 8 weeks of initial symptoms e.g. jaundice
• Subacute liver failure: onset within< 26 weeks
• Long term- HCC and liver cirrhosis

Question 11

Pre- exposure prophylaxis hepatitis B

Answer 11

• Practice safe sex
• Cover wounds well
• Cleaning up spilled blood
• Avoid illegal street drugs or use sterile equipment
• No sharing sharp items such as razors, toothbrushes, nail clippers and earrings
• Active immunization (vaccine) - recommended for all infants, all children under 19 and unvaccinated adults who are in risk groups

Question 12

Post- exposure prophylaxis hepatitis B

Answer 12

• unvaccinated individual or not fully vaxxed– HBIG and hepatitis B vaccine
• Fully vaccinated but with unknown status or anti-HBs<10ml IU/ ml: 1 dose HBIG + 3 consecutive doses of hepatitis B vaccine + retest of anti-HBs levels
• In infants whose mother has HBV— 1 dose of HBIG and 1 dose of vaccine (should be done within 12 hrs after birth).

Question 13

MELD score and Child-pugh score used in Hepatitis B

Answer 13

MELD Score: used to prioritize adult patients for liver transplants. Determines how
soon a person will need a liver transplant. Calculations based on 3 lab results: total
bilirubin, INR-prothrombin time, creatinine

Child-Pugh Score: Used to classify the severity of cirrhosis based on laboratory markers
and presence of ascites and hepatic encephalopathy.
Class A (5-6 points) : 1 year survival rate of almost 100%
Class B (7-8points) : 1 year survival rate of about 80%
Class C (10-15points); 1 year survival rate of about 45%. Morbidity and mortality rate
results from multiple severe complications such as hepatorenal syndrome.

Question 14

Viruses casuing Hepatitis

Answer 14

Hepatitis A Virus, Hepatitis B Virus, Hepatitis C Virus, Hepatitis D Virus, Hepatitis E virus, EBV, CMV