Streptococcal and EBV Serology (Exam 3)

What do serological tests do in regard to viral infections?

- Monitor the course of infection

- Detect past infection

- Assess immune status and current infection

Detecting past infection means seeing the presence of ______.

IgG

Assessing immune status and current infection means seeing the presence of ______.

IgM

Molecular tests can be done to detect ______ infection.

current

EBV can cause ______ and ______.

infectious mononucleosis, lymphomas

EBV is transmitted via ______ secretions, direct personal contact, and transfusions.

upper respiratory tract

EBV initially infects the epithelial cells of the throat/upper respiratory tract, then it infects ______.

B cells

EBV-infected B cells become ______, secreting what?

polyclonal

Many different types of Abs

In a blood smear, infectious mononucleosis shows increased presence of ______.

lymphocytes/reactive lymphocytes

Serologically, infectious mononucleosis will show ______ Abs and Abs to certain EBV ______.

heterophile, antigens

Heterophile Abs are capable of reacting with ______ from two or more unrelated species.

similar antigens

Infectious mononucleosis is associated with heterophile ______ Abs.

IgM

These Abs are reactive to what kinds of RBCs?

- Horse

- Sheep

- Bovine

A ______ test is often done for infectious mononucleosis detection.

rapid agglutination test

This test is diagnostic if ______ from a patient displaying ______.

positive, S/Sx

The antigen in a rapid agglutination test is purified ______ extract.

bovine RBC

Early EBV antigens appear during the ______ cycle.

lytic

Early antigens can have ______ or ______ distribution.

diffuse (cytoplasm/nucleus), restricted (cytoplasm)

With infectious mononucleosis, Anti-VCA-IgM detection indicates ______ infection.

acute/current

With infectious mononucleosis, Anti-VCA-IgG detection indicates ______ infection.

past/waning

Anti-______ indicates early infection, while Anti-______ indicates latent/past infection.

Anti-EA-D, Anti-EBNA

Group A streptococcus (GAS) is able to completely ______ RBCs when grown in culture.

lyse

What are the main S. pyogenes virulence factors?

- Streptolysin O

- DNase B

- Hyaluronidase

- NADase

What are some common diseases associated with GAS infection?

- Pharyngitis (Strep throat)

- Streptococcal pyoderma (impetigo)

What are some secondary GAS-associated diseases that can occur after an initial GAS infection and cessation?

- Rheumatic fever

- Glomerulonephritis

Rheumatic fever occurs when GAS Abs can't ______.

"turn off"

These GAS Abs will attack the tissue lining the ______.

heart valves

Glomerulonephritis occurs when ______ are deposited in glomeruli.

immune complexes

This stimulates an ______ response and ______ GFR.

inflammatory, decreased

GAS can be diagnosed via ______ or ______.

culture, rapid assays

Rapid assays detect GAS ______.

antigens

Lateral flow immunoassay is used frequently for ______ antigens.

streptococcal

With a lateral flow immunoassay, the GAS antigen is extracted from a ______ swab.

throat

Why must streptococcal Ab detection be used for rheumatic fever and/or post-streptococcal glomerulonephritis?

Because Abs to exotoxins are used for detection of disease

What are the most diagnostically important streptococcal Abs?

- Anti-streptolysin O

- Anti-DNase

- Anti-NADase

- Anti-hyaluronidase

ASO testing detects patient Abs toward ______.

streptolysin O

Streptolysin O is an enzyme produced by GAS that can ______.

lyse RBCs

Positive ASO = ______

recent GAS infection

ASO titers will increase ______ weeks after infection and peak ______ weeks after initial S/Sx.

1-2, 3-6

ASO can only be detected in 85% of ______ patients.

acute rheumatic fever

ASO is not observed in individuals with ______.

skin infection (pyoderma)

ASO testing can produce false positives with group ______ and ______ strep.

C, G

Anti-DNase B testing is useful in patients suspected of having post-streptococcal ______ due to skin infection.

glomerulonephritis

Anti-DNase B testing is highly specific for ______.

GAS

______ is used for anti-DNase B testing.

Nephelometry

Pt serum + DNase B reagent = immune complex?

Streptozyme testing is a ______ screening test for patient Abs against strep antigens.

card agglutination

What are the 5 extracellular strep antigens that streptozyme testing detects?

- Streptolysin

- Hyaluronidase

- Streptokinase

- NADase

- DNase B

Streptozyme testing can be used in conjunction with ______ and ______ testing, which is helpful when it is negative.

ASO, anti-DNase B