hepatitis Flashcards
Primary hepatitis
Inflammation of the liver due to viral infection
Hepatitis A AKA
Enterovirus 72
Hepatitis A Family
Picornaviridae
Hepatitis A Characteristics
Non-enveloped, icosahedral, RNA virus
Hepatitis A Disease Nature
Self-limited, does not result in chronic infection; same with Hepa E
Hepatitis A Vaccine
Available
Hepatitis A Causative Agent
Hepatitis A virus
Hepatitis A Common Cause
Infectious hepatitis, most common cause of hepatitis
Hepatitis A Onset
Abrupt onset
Hepatitis A Incubation Period
15 to 50 days (average 28 days)
Hepatitis A Detection
Detected in stool, not serum
Hepatitis A Mode of Transmission
Fecal-oral route
Hepatitis A Risk Factors
Travellers, sex contacts, household contacts, MSM, drug users, clotting-factor disorders
Hepatitis A Transmission Routes
Close person-to-person contact, sexual contact, contaminated food or drinks
Hepatitis A Markers of Infection
Early virus shedding in stool, IgM Anti-HAV, IgG Anti-HAV
Hepatitis A Test Methods
ELISA (indirect and direct), Radioimmunoassay (RIA)
Hepatitis A Serology - Acute Infection
IgM anti-HAV positive, IgG anti-HAV negative
Hepatitis A Serology - Old Infection
IgM anti-HAV negative, IgG anti-HAV positive
Hepatitis A Serology - Incubation/No Infection
IgM anti-HAV negative, IgG anti-HAV negative
Hepatitis E Virus (HEV) Characteristics
32-34 nanometers, calicivirus, resembles Hepatitis A
Hepatitis E Mode of Transmission
Fecal-oral route, often via contaminated water
Hepatitis E Genus
Hepevirus
Hepatitis E Genotypes
HEV 1, 2 (waterborne), HEV 3, 4 (zoonotic)
Hepatitis E Diagnosis
Based on symptoms or exposure in endemic regions, serology
Hepatitis E Risk for Pregnant Women
May develop fulminant liver failure and death
Hepatitis E Mortality Rate
High mortality rate in women
Hepatitis E Laboratory Diagnosis
Electron microscopy, Indirect ELISA, RT-PCR
Hepatitis G Virus Characteristics
RNA virus, enveloped, Flaviviridae family
Hepatitis G Mode of Transmission
Contact with blood, sexually transmitted, transplacental
Hepatitis G Pathogenicity
Common worldwide, but seems non-pathogenic
Hepatitis B is also known as
Serum hepatitis, Australian hepatitis
1st hepatitis to be discovered by Dr. Baruch Blumberg in 1963
Hepatitis B
Type of genome in Hepatitis B virus
Double-stranded DNA
Family of Hepatitis B virus
Hepadnaviridae
Hepatitis B virus is also known as
Dane Particle
Primary organ targeted by Hepatitis B virus
Liver
Incubation period of Hepatitis B
45 to 160 days (average 120 days)
Modes of transmission for Hepatitis B
Direct contact with infectious blood, semen, or other body fluids, including birth to an infected mother, sexual contact, and sharing contaminated needles or equipment
Best indicator for early or acute Hepatitis B infection
HBsAg (Australia antigen)
Marker found in the core of the intact Hepatitis B virus but not in serum
HBcAg (core antigen)
Serologic marker indicating high levels of Hepatitis B virus and high infectivity
HBeAg (envelope antigen)
First antibody to appear during Hepatitis B infection, seen during the window period
Anti-HBc
Serologic evidence of recovery phase in Hepatitis B
Anti-HBe
Marker for long-term immunity to Hepatitis B
Anti-HBs
HBsAg, Anti-HBc, Anti-HBs are all negative
Susceptible to acquire Hepatitis B infection
Anti-HBc positive only
Window period
Anti-HBc is positive, Anti-HBs is positive
No active infection, has immunity due to natural infection (previously infected with Hepatitis B)
Anti-HBs is positive only
Immune due to Hepatitis B vaccination
Anti-HBs and Anti-HBc positive
Recovery
HBsAg is positive, Anti-HBc is positive, IgM anti-HBc is positive, Anti-HBs is negative
Acutely infected with Hepatitis B
HBsAg is positive, Anti-HBc is positive, IgM anti-HBc is negative, Anti-HBs is negative
Chronically infected with Hepatitis B
HBsAg is negative, Anti-HBc is positive, Anti-HBs is negative
Possible interpretations: 1. Resolved infection (most common), 2. False-positive anti-HBc (susceptible), 3. ‘Low-level’ chronic infection, 4. Resolving acute infection, 5. Window stage of infection
Viral load in HBV infection definition
Measurement of the viral agent in the blood; signifies if a patient can be infectious
HBV vaccine (introduced in 1982) made by a recombinant strain
Yeast Saccharomyces cerevisiae (common baker’s yeast)
1st generation HBV detection test
Ouchterlony test: precipitation reaction using double diffusion in double dimension
2nd generation HBV detection tests
Include Counter Immunoelectrophoresis (precipitation with electrical current), Rheophoresis (precipitation by evaporation), and Complement Fixation (based on complement binding to antigen-antibody complexes)
3rd generation HBV detection tests
Include Reverse Passive Latex Agglutination (agglutination test for antigen detection), Reverse Passive Hemagglutination (hemagglutination test for antigen detection), ELISA (enzyme-linked immunosorbent assay for antigen/antibody confirmation), and RIA (radioimmunoassay for sensitive antigen/antibody detection)
IgM anti-HBcAg
Indicates a new Hepatitis B infection
IgG anti-HBcAg
Indicates an old Hepatitis B infection
Both IgG and IgM anti-HBcAg
Indicates a mid-stage Hepatitis B infection
Anti-HBeAg in serologic testing
Indicates low infectivity of Hepatitis B virus
Hepatitis C family and genus
Family: Flaviviridae; Genus: Hepacivirus
Hepatitis C description
Blood-borne hepatitis; also known as post-transfusion hepatitis
Incubation period for Hepatitis C
14 to 180 days (average 45 days)
Cause of Hepatitis C
Hepatitis C virus (HCV)
Confirmatory test for Hepatitis C
RIBA (Recombinant Immunoblot Assay)
Mode of transmission (MOT) for Hepatitis C
Parenteral (via blood contact)
Surrogate testing for NANBV/HCV in donated blood
Includes ALT level detection and Anti-HBc detection (via RIA or ELISA using Enzyme Inhibition Technique)
Serologic test for Anti-HCV
ELISA and RIA
Antibody detection for Hepatitis C
If Anti-HCV is negative, no infection; if present, perform RNA testing
Interpretation of Hepatitis C antibody and RNA test results
If RNA is present, further testing is needed; If antibody is present but RNA is absent, no current infection; If both antibody and RNA are present, active infection
Hepatitis D (Delta Hepatitis) agent
Hepatitis D virus (HDV), also known as Delta Virus
Mode of transmission (MOT) for Hepatitis D
Parenteral and sexual transmission
Characteristics of Hepatitis D virus (HDV)
RNA virus that requires HBV for replication; uses HBV’s envelope (HBsAg) to replicate
Co-infection with HBV
Simultaneous infection with HBV and HDV
Superinfection with HBV
HDV infects cells already infected with HBV, leading to faster replication and severe hepatocyte damage
Serologic markers for HDV
HDV Ag (early stage, not useful due to rapid disappearance), IgM anti-HDV, total anti-HDV (IgM and IgG) for acute phase
Chronic infection indicator for HDV
Presence of anti-HDV IgG indicates chronic infection
Laboratory diagnosis of Hepatitis D
Indirect ELISA for Anti-HDV and Anti-HBc IgM
Serologic markers for acute HDV infection
HDV Ag (early stage), IgM anti-HDV, total anti-HDV
Co-infection marker for HDV
IgM anti-HDV + HBsAg + IgM anti-HBc
Superinfection marker for HDV
Absence of IgM anti-HBc
Chronic infection marker for HDV
Anti-HDV IgG