Download Interpretation of Serological Tests - f

Out line
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Overview of viral hepatitis
Structure of HBV
Distribution
Transmission
Possible out come of Hepatitis infection
Serological course of acute and chronic infection
Laboratory Diagnosis/interpretation
Treatment \Prevention
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Introduction
• Hepatitis = 'inflammation of the liver'.
• Five medically important viruses are
commonly described as “hepatitis viruses”:
HAV,HBV,HCV,HDV,HEV.
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Overview of Viral hepatitis
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Hepatitis B Virus
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HBV : Structure
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Hepatitis B In the World
• An estimated 240 million people are
chronically infected with hepatitis B.
• More than 780 000 people die every year
due to complications of hepatitis B,
including cirrhosis and liver cancer
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3、HBV: Modes of Transmission
 Parenteral - IV drug abusers, health workers are
at increased risk.
 Sexual - sex workers and homosexuals are
particular at risk.
 Perinatal(Vertical) - mother(HBeAg+) →infant.
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High-risk groups for HBV infection
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People from endemic regions
Babies of mothers with chronic HBV
Intravenous drug abusers
People with multiple sex partners
patients requiting blood and blood product
treatments
• Health care personnel who have contact with
blood
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6、Clinical Features
Incubation period:
Average 60-90 days
Range 45-180 days
Insidious onset of symptoms.
Tends to cause a more severe disease than Hepatitis A.
Clinical illness (jaundice):
<5 yrs, <10%
≥ 5 yrs, 30%-50%
1/3 adults-no symptoms
Clinical Illness at presentation
10 - 15%
Acute case-fatality rate:
Chronic infection:
infections
Premature mortality from
chronic liver disease:
0.5%-1%
< 5 yrs, 30%-90%
≥ 5 yrs, 2%-10%
More likely in ansymptomatic
15%-25%
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Possible Outcomes of HBV Infection
Acute hepatitis B infection
3-5% of adultacquired infections
95% of infantacquired infections
Chronic HBV infection
Chronic hepatitis
12-25% in 5 years
6-15% in 5 years
Cirrhosis
Hepatocellular
carcinoma
Death
20-23% in 5 years
Liver failure
Liver transplant
Death
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Typical Serological
Markers for Acute
Hepatitis B Infection
Acute Hepatitis B Virus Infection with Recovery
Typical Serologic Course
Titer
0
4
8
12 16 20 24 28 32 36
52
100
Weeks after Exposure
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Acute Hepatitis B Virus Infection with Recovery
Typical Serologic Course
Titer
HBsAg
0
4
8
12 16 20 24 28 32 36
52
100
Weeks after Exposure
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Acute Hepatitis B Virus Infection with Recovery
Typical Serologic Course
HBeAg
Titer
HBsAg
0
4
8
12 16 20 24 28 32 36
52
100
Weeks after Exposure
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Acute Hepatitis B Virus Infection with Recovery
Typical Serologic Course
HBeAg
anti-HBe
Titer
HBsAg
0
4
8
12 16 20 24 28 32 36
52
100
Weeks after Exposure
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Acute Hepatitis B Virus Infection with Recovery
Typical Serologic Course
Symptoms
HBeAg
anti-HBe
Titer
HBsAg
0
4
8
12 16 20 24 28 32 36
52
100
Weeks after Exposure
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Acute Hepatitis B Virus Infection with Recovery
Typical Serologic Course
Symptoms
HBeAg
anti-HBe
Titer
IgM anti-HBc
HBsAg
0
4
8
12 16 20 24 28 32 36
52
100
Weeks after Exposure
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Acute Hepatitis B Virus Infection with Recovery
Typical Serologic Course
Symptoms
HBeAg
Titer
anti-HBe
IgG anti-HBc
IgM anti-HBc
HBsAg
0
4
8
12 16 20 24 28 32 36
52
100
Weeks after Exposure
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Acute Hepatitis B Virus Infection with Recovery
Typical Serologic Course
Symptoms
HBeAg
Titer
anti-HBe
IgG anti-HBc
IgM anti-HBc
anti-HBs
HBsAg
0
4
8
12 16 20 24 28 32 36
52
100
Weeks after Exposure
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Acute Hepatitis B Virus Infection with Recovery
Typical Serologic Course
Symptoms
HBeAg
Titer
anti-HBe
IgG anti-HBc
IgM anti-HBc
anti-HBs
HBsAg
Window
Period
0
4
8
12 16 20 24 28 32 36
52
100
Weeks after Exposure
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Typical Serological
Markers for Chronic
Hepatitis B Infection
Chronic Hepatitis B Virus Infection
Typical Serologic Course
Titer
HBsAg
0
1
2
3
4
5
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9
10
Years After Exposure
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Chronic Hepatitis B Virus Infection
Typical Serologic Course
Titer
HBsAg
IgM, anti-HBc
0
1
2
3
4
5
6
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8
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10
Years After Exposure
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Chronic Hepatitis B Virus Infection
Typical Serologic Course
HBsAg
Titer
IgG anti-HBc
0
1
2
3
4
5
6
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8
9
10
Years After Exposure
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Chronic Hepatitis B Virus Infection
Typical Serologic Course
HBeAg
HBsAg
Titer
IgG anti-HBc
0
1
2
3
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5
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10
Years After Exposure
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Chronic Hepatitis B Virus Infection
Typical Serologic Course
HBeAg
Anti-HBe
HBsAg
Titer
IgG anti-HBc
0
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2
3
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5
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10
Years After Exposure
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Acute vs. Chronic HBV Infection
Acute
• HBsAg+ < 6 mos.
• IgM anti-HBc +
positive
• Infection will resolve
and person will have
lifelong immunity
• HBsAb+ and HBcAb+
Chronic
• HBsAg + for at least 6
months
• Also known as a “carrier”
• Infection does not resolve
and the person remains
infectious
• HBsAb- and HBcAB+
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Laboratory Tests for HBV
• Serology:
– Many tests available – most common tests are
Enzyme Immunoassays (like ELSA, CLIA)
• Molecular:
– HBV DNA (quantitative)
– HBV resistance testing
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Hepatitis B – Laboratory Tests
Serologic markers:
1) HBsAg (Hepatitis B surface antigen):
• if positive, person is infectious
2) Anti-HBs (Antibody to HBV surface antigen):
• indicates immunity to HBV and protection
from disease
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Hepatitis B – Laboratory Tests
Serologic markers:
3) Anti - HBc (Antibody to HBV core antigen):
• Total - indicates past or active infection;
present whether person is immune or
chronic carrier
• IgM - early indicator of acute infection
• No antigen test
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Hepatitis B – Laboratory Tests
Serologic markers:
4) HBeAg (Hepatitis Be antigen):
• indicates person is highly infectious
5) Anti-HBe (Antibody to HBVe antigen):
• prognostic for resolution of infection;
less infectious;
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Interpretation of serological
tests
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Interpretation of Serological Tests
Test
HBsAg
anti-HBc
anti-HBs
Results
Negative
Negative
Negative
Interpretation
???
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Interpretation of Serological Tests
Test
HBsAg
anti-HBc
anti-HBs
Results
Negative
Negative
Negative
Interpretation
Susceptible
(Never infected
or vaccinated)
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Interpretation of Serological Tests
Test
HBsAg
anti-HBc
anti-HBs
Results
Negative
Negative
Positive
Interpretation
???
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Interpretation of Serological Tests
Test
HBsAg
anti-HBc
anti-HBs
Results
Negative
Negative
Positive
Interpretation
Immune
(Due to vaccine)
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Interpretation of Serological Tests
Test
HBsAg
anti-HBc
anti-HBs
Results
Negative
Positive
Positive
Interpretation
???
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Interpretation of Serological Tests
Test
HBsAg
anti-HBc
anti-HBs
Results
Negative
Positive
Positive
Interpretation
Immune
(Resolved
Infection)
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Interpretation of Serological Tests
Test
HBsAg
anti-HBc
IgM anti-HBc
anti-HBs
Results
Positive
Positive
Positive
Negative
Interpretation
???
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Interpretation of Serological Tests
Test
HBsAg
anti-HBc
IgM anti-HBc
anti-HBs
Results
Positive
Positive
Positive
Negative
Interpretation
Acutely Infected
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Interpretation of Serological Tests
Test
HBsAg
anti-HBc
anti-HBs
IgM anti-HBc
Results
Positive
Positive
Negative
Negative
Interpretation
???
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Interpretation of Serological Tests
Test
HBsAg
anti-HBc
anti-HBs
IgM anti-HBc
Results
Positive
Positive
Negative
Negative
Interpretation
Chronically
Infected
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Interpretation of Serological Tests
Test
HBsAg
anti-HBc
anti-HBs
Results
Negative
Positive
Negative
Interpretation
???
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Interpretation of Serological Tests
Test
HBsAg
anti-HBc
anti-HBs
Results
Negative
Positive
Negative
Interpretation
Four Possible Interpretations
1. Resolved infections (most common)
2. False Positive Anti HBc
3. ‘low level’ Chronic infection
4. Resolving Acute infections
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Treatment
• Interferon
• Lamivudine (Epivir HBV)
(relapse ,drug resistance)
• Adefovir dipivoxil (Hepsera)
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Prevention
• Vaccination
- highly effective recombinant vaccines
• Hepatitis B Immunoglobulin (HBIG)
-exposed within 48 hours of the incident/ neonates
whose mothers are HBsAg and HBeAg positive.
• Other measures
-screening of blood donors, blood and body fluid
precautions.
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