SEROLOGY Flashcards
Hepatitis A family
Picornaviridae
Hepatitis A is also known as
Enterovirus 72
Hepatitis ___ characteristics:
Has a viral capsid
non-enveloped icosahedral
RNA gene
Hepatitis A
Self-limited disease that does not result in chronic infection (milder than other types)
Hepatitis A
Most common cause of hepatitis virus
Hepatitis A
Incubation period of Hepatitis A
15 to 50 days (average of 28 days)
Hepatitis A is detected through ______ sample
stool
Mode of transmission of Hepa A
Fecal-oral route
Close person to person contact with an infected person
Sexual contact with an infected person (direct oral-anal contact)
Ingestion of contaminated food or drinks
Hepa A Markers of infection
Early shedding of the virus in the stool
Appearance of IgM Anti-HAV with the onset of symptoms (icterus/jaundice)
Development of Anti-HAV IgG and immunity on recovery
Increased liver enzyme levels for Hepa A
SGPT/ALT (significantly)
SGOT (increased)
Nucleotidase
Tests for HEPA A
ELISA (indirect: antibody)
RIA
Serology of HEPA A
IgM anti-HAV: Positive
IgG anti-HAV: Negative
Acute infection
Serology of HEPA A
IgM anti-HAV: Negative
IgG anti-HAV: Positive
Old infection
Serology of HEPA A
IgM anti-HAV: negative
IgG anti-HAV: negative
incubation/no infection
Hepatitis B AKA
serum hepatitis
Hepatitis B virus AKA
DANE PARTICLE
Hepatitis that attacks liver that causes acute and chronic liver disease
Hepatitis B
Incubation period of Hepatitis B
45 to 160 days (average of 120 days)
Hepatitis that is double stranded DNA virus
Hepatitis B
Virus family of HEPATITIS B
Hepadnaviridae
Mode of transmission for HEPA B
Direct contact with infectious blood, semen, and other body fluids primarily through:
Birth to an infected mother (vaginal)
Sexual contact with an infected person
Sharing of contaminated needles, syringe, or other injection drug equipment
Needle sticks or other sharp instrument injuries
Serologic Markers for HBV
HBsAg
HBcAg
HBeAg
Anti-HBc
Anti-HBe
Anti-HBs
HBsAg
Anti-HBc
Anti-HBs
All are negative
Susceptible to acquire infection
HBsAg: Negative
Anti-HBc: Positive
Anti-HBs: Positive
No infection
Has immunity due to natural infection (has been infected)
HBsAg: Negative
Anti-HBc: Negative
Anti-HBs: Positive
Immune due to hepatitis B vaccination
HBsAg: Positive
Anti-HBc: Positive
IgM anti-HBc: Positive
Anti-Hbs: Negative
Acutely infected
HBsAg: Positive
Anti-HBc: Positive
IgM anti-HBc: Negative
Anti-Hbs: Negative
Chronic infection
HBsAg: Negative
Anti-HBc: Positive
Anti-HBs: Negative
Resolved infection (most common)
False-positive anti-HBc (susceptible)
Low level chronic infection
Resolving acute infection
Window stage of infection
measurement of the viral agent in the blood; signifies if a patient can be infectious
Viral load
Yeast recombinant strain of HBV Vaccine (1982) - common baker’s yeast
Saccharomyces cerevisiae
Tests available for HBV detection:
1st generation
Ouchterlony
Ouchterlony principle for HBV detection
precipitation reaction; double diffusion, double dimension
Tests available for HBV detection:
2nd generation
Counter Immunoelectrophoresis
Rheophoresis
Complement fixation
Principle of Rheophoresis
precipitation by evaporation
Principle of Counter Immunoelectrophoresis
precipitation with current
Tests available for HBV detection:
3rd generation
Reverse passive latex agglutination
Reverse passive hemagglutination
ELISA
RIA
Diseases states caused by HBV
Acute hepatitis
Fulminant hepatitis
Chronic
Co-infection with Hepa D
Outcome disease from unresolved Hepatitis B
Hepatoma
Outcome disease from unresolved HPV
Cervical cancer
Outcome disease from unresolved EBV
Nasopharyngeal cancer
Serologic Tests for HBV
HBsAg
HBeAg
Anti-HBc
Anti-HBs
Anti-HBe
Positive result for HBsAg indicates:
presence of ongoing disease; can either be chronic or acute
Positive result for Anti-HBsAg indicates:
no active disease; the person is already immuned; long term immunity
Marker of Hepatitis B that has no antigen and is only found on intact cells
HBcAg
Positive result for IgM and HBcAg indicates:
New infection
Positive result for IgG and anti-HBcAg
Old infection
Presence of both IgG and IgM in Hepatitis B indicates:
Mid infection
Envelope antigen of Hepa B
HBeAg
Positive HBeAg indicates:
high infectivity
Positive Anti-HBeAg indicates:
Low infectivity
Anti–HBV drug
lamivudine
Confirmatory for Hepatitis B infection
ELISA
Hepatitis C virus family:
Flaviviridae
Blood-borne hepatitis; post-transfusion hepatitis:
Hepatitis C
Incubation period of Hepatitis C
14 to 180 days (average of 45 days)
Confirmatory test for Hepatitis C
RIBA (Recombinant Immunoblot Assay)
Serologic Tests for Hepatitis C
Surrogate testing for detecting NANBV/HCV in donated blood (level detection for ALT, Anti-HBc)
Serologic Tests for antibody against HCV Ag (Anti-HCV) (ELISA, RIA)
HCV antibody nonreactive indicates:
No HCV antibody detected
HCV antibody reactive
Presumptive for HCV infection
HCV antibody reactive, HCV RNA detected
Current HCV infection
HCV antibody reactive, HCV RNA not detected
Interpretation:
No current HCV infection
RNA virus transmitted parentally and can replicate only with the help of HBV
Hepatitis D (HDV)
HDV is also known as:
Delta Virus
Helical nucleocapsid actually uses HBV’s envelope, HBsAg (only replicates in cells infected with HBV)
Hepatitis D
Coinfection with HBV - HDV mechanism:
simultaneously replicates or infect with HBV
Superinfection with HBV- HDV mechanism
faster replication; rate of damage and infection to hepatocytes
can infect cells on top of the active infection of HEPA D
Serologic Markers for HDV
HDV Ag
IgM anti-HDV and total anti-HDV (IgM and IgG)
Presence of IgM anti-HDV and HBsAg together IgM anti-HBc-
Absence of IgM anti-HBc
Presence of anti-HDV IgG
Serologic marker that is found in early stage of infection of HDV; rapidly disappears on plasma thus, not very useful
HDV Ag
Serologic marker for HDV for detecting acute phase
IgM anti-HDV
Total anti-HDV (IgM and IgG)
Serologic marker for HDV that detects co-infection
Presence of :
IgM anti-HDV
HBsAg
IgM anti-HBc
Serologic marker for HDV that indicates presence of superinfection HDV
Absence of IgM anti-HBc
Serologic marker for HDV that indicates chronic infection
Presence of anti-HDV IgG
Size of Hepatitis E virus
32-34 nanometer
HEPA E is also known as
calicivirus
MOT for HEV
fecal oral route (often contaminated water)
HEV resembles
HAV
Pregnant women with HEV may develop:
fulminant liver failure and death
Characteristics of Hepatitis G
RNA- enveloped
Family virus of Hepatitis G
Flaviviridae
MOT of Hepatitis G
contact with blood
sexually transmitted
transplacental
HGV common worldwide but seems to be ______
non-pathogenic
also known as kissing disease
infectious mononucleosis
Infectious Mononucleosis MOT
exchange of mouth fluid
Causative agent of Infectious mononucleosis
Epstein Barr Virus
Cell that is infected by Epstein Barr Virus
B lymphocytes
Epstein Barr Virus inhabits:
nasopharyngeal tissues (asymptomatic carriers)
atypical lymphocytes/reactive lymphocytes (infected with EBV
Downey cells
Downey cells causes ___ in RBC
cytoplasmic indentation
EBV infection is most common during ages ____
15 to 25 (adolescence and early adulthood)
Antibodies formed from Forssman experiment (Guinea pig cells + Rabbit → ___)
Anti-Guinea pig cells and Anti-sheep cells
used for any substance that stimulated the formation of sheep hemolysin (anti-sheep cells)
Forssman antigen
antibodies produced by unrelated species which can cross-react with the same antigen
Heterophil antibodies
Heterophil antibodies in Infectious Mononucleosis reacts with
sheep, ox, horse cells
Heterophil antibodies in Infectious Mononucleosis does not react with
Guinea pig cells
Heterophil antibodies of Forssman is negative for:
beef or ox cells
Heterophil antibodies in serum sickness is positive to:
Sheep Cells
Ox/Beef Cells
Horse cells
Guinea pig cells
presumptive or screening test for heterophil antibodies (detects all heterophil antibodies; cannot determine the specificity of heterophil antibody)
Paul Bunnel Test
Principle for Paul Bunnel Test
Hemagglutination
Reagent for Paul Bunnel Test
2% suspension of sheep rbcs
Antibody for Paul Bunnel Test
Heterophil antibodies in patient’s serum
Positive result for Paul Bunnel Test
hemmaglutination - presence of heterophil antibodies
Davidson differential test principle:
absorption hemagglutination
Antigen for Davidson differential test:
Guinea pig kidney cells and Beef RBCs
Antibody for Davidson differential test
Heterophil in patient’s serum
Indicator cells for Davidson Differential Test
Sheep RBCs
Two steps for Davidson differential test
Absorption, Hemagglutination
Absorption result for tube 1 in davidson differential test:
Positive (decrease antibody titer)
Absorption result for tube 2 in davidson differential test:
Negative (retain high antibody titer)
Davidson differential test absorption:
Tube 1 contains
Beef cells + heterophil abs from paul bunnel test
Davidson differential test absorption:
Tube 2 contains
guinea pig kidney cells + heterophil abs from paul bunnel test
Davidson differential test hemagglutination:
Tube 1 contains
beef cells + sheep RBC
Davidson differential test hemagglutination
Tube 2 contains:
Guinea pig kidney cells + Sheep RBC
Hemagglutination result for tube 1 in davidson differential test:
weak agglutination (+1)
Hemagglutination result for tube 2 in davidson differential test:
+4 (strong agglutination)
Davidson Differential Test:
Positive absorption in step 1
Result for step 2:
Weak reaction
Davidson Differential Test:
Negative absorption in step 1
Result for step 2
Strong reaction
Absorption pattern:
Beef RBCs: negative
Guinea pig kidney cells: positive
Forssman
Absorption pattern:
Beef RBCs: positive
Guinea pig kidney cells: negative
Infectious mononucleosis
Absorption pattern:
Beef RBCs: positive
Guinea pig kidney cells: positive
Serum sickness
Agglutination pattern after absorption:
Row 1 (Beef RBCs): 4+
Row 2 (Guinea pig kidney cells): 1+
Forssman
Agglutination pattern after absorption:
Row 1 (Beef RBCs): 1+
Row 2 (Guinea pig kidney cells): 4+
Infectious mononucleosis
Agglutination pattern:
Row 1 (Beef RBCs): 2+
Row 2 (Guinea pig kidney cells): 2+
Serum sickness
Principle for Monospot test
Absorption hemeagglutination
Antigen for Monospot Test
Guinea pig kidney cells and beef RBCs
Antibody for Monospot Test
Heterophil abs in px’s serum
Rapid Differential Slide Test using Papain-Treated Sheep RBCs principle:
Hemagglutination
Inactivates receptor for antibodies in Rapid Differential Slide Test
Papain
Native Sheep RBCs: Agglutination
Papain-treated Sheep RBCs: No/Weak agglutination
interpretation:
Normal serum and IM serum
Native Sheep RBCs: Agglutination
Papain-treated Sheep RBCs: Agglutination
Serum sickness and other heterophil Antibodies
HIV Family
Retroviridae
Subfamily of HIV
Lentivirus, Oncovirus
Human Immunodeficiency Virus characteristics
Enveloped
Coiled nucleocapsid
Icosahedral with single stranded RNA
Unique enzyme of HIV
reverse transcriptase
Replication site of HIV
Inside the nucleus (CD4+ of cell surface)
Predominant HIV type
HIV 1
First identified in France by Luc Montagnier
HIV 1
In USA, HIV 1 is identified by
Robert Gallo (1983)
Jay Levy (1984)
HIV 1 is formerly called
Human T-cell Lymphocytic Virus type III (HTLV-III)
Lymphadenopathy associated Virus (LAV)
AIDS -associated retrovirus (ARV)
HIV 2 is prevalent in
West Africa
less pathogenic, lower rate transmission HIV
HIV 2
Mode of transmission for HIV
Mainly through sexual intercourse
Transfer of blood or blood products
Babies can be infected before or during birth and from breast feeding
Parental drug use
Codes for core structural (group antigen) proteins
VIRAL GENE PRODUCT:
P24, p18, p15
Gene for core structural (group antigen) proteins
Gag
Pol (polymerase) function/s
Transcribes ssRNA into dsDNA
Viral gene product that transcribes ssRNA into dsDNA
Reverse transcriptase
Viral gene product that binds to CD4+ receptors for HIV infection
gp160
Viral gene product required for viral infusion of cell
gp41
gene for gp160 and gp41
Env (envelope)
Primary effects of HIV infections
Extreme leukopenia (lymphocytes, CD4+ lymph)
Formation of giant T-cells and other syncytia
Infected macrophages release the virus in central nervous system
Allows human immunodeficiency virus to spread directly from cell to cell making it faster to replicate
Formation of giant T-cells and other syncytia
Secondary effects of HIV
Destruction of CD4 lymphocytes: allows opportunistic infections and malignancy to infect the patient
Steps for HIV infection diagnosis
Initial screening
Confirmatory
Initial screening of HIV is followed up by _____ to rule out false positives
Western Blot
Laboratory Tests for HIV
ELISA (direct/indirect)
Western Blot or Immunofluorescent Test
Indirect Immunofluorescence assay
3 bands for HIV confirmatory
p24, gp41, gp120/gp160
Test to detect HIV in infected cells; also a confirmatory (HIV present in CD4+ cells
Indirect Immunofluorescence assay
Tests for Detecting HIV Genes
In situ hybridization
Filter hybridization
SOUTHERN BLOT
Hybridization-DNA
DNA Amplification
PCR - tests HIV RNA
NORTHERN BLOT - measures mRNA antigen
Diagnosis of AIDS is made when a person meets the following criteria:
1.Positive for the virus
2.They fulfill one of the additional criteria:
a)CD4: <200 cells/ml of blood
b)CD4: < 14% of all lymphocytes
c)They experience one or more of a CDC provided list of AIDS defining illnesses.
> 200 CD4+ cells/ml of blood classification
HIV positive
<200 CD4+ cells/mL of blood classification
AIDS
Stage of HIV clinical manifestation:
a)px is either asymptomatic or may show lymphadenopathy
b)Resembles infectious mononucleosis
Primary stage
Stage of HIV clinical manifestation:
a)State is known as the ARC (AIDS-Related Complex)
b) Quantitative T cell deficiencies with inverted CD4:CD8 ratio (normal 2:1; inverted; 0.5:1)
Intermediate stage
Stage of HIV clinical manifestation:
a)2-10 years after initial infection
b)A syndrome of CD4 depletion resulting in opportunistic infections and cancers suggestive of cell-mediated immunity defects
Final stage
Opportunistic pathogens for HIV
Pneumocystis carinii (Pneumocystis jirovecii)
M. avium-intracellulare complex
Candida albicans
Cryptosporidium parvum
Toxoplasma gondii
Cryptococcus neoformans
Herpes Simplex (I and II)
Legionella spp.
most frequently observed malignancy of HIV
Kaposi’s sarcoma
Tumors in skin and linings of internal organs, lymphomas, cancers of rectum and lung
Kaposi’s sarcoma
Kaposi’s sarcoma is caused by:
HSV type 8
Window period for HIV
6-8 weeks
First antibody detected in serum; persist throughout the infection of HIV
Anti-gp41
New confirmatory for HIV in the Philippines
rHIVda (rapid HIV diagnostic algorithm)
Positive reporting of HIV test in rHIVda is recorded after ______
Positive result for Test 3
If Tests 1, 2, and 3 is negative in rHIVda, report the result as _____
inconclusive
Patients with negative rHIVda results should comeback after _______
2-6 weeks