Infectious Mononucleosis and Epstein Barr Virus Flashcards
What 4 viruses belong in the Herpesviridae family and establish latency and can recur when the host is stressed?
- Herpes Simplex Virus
- Cytomegalovirus
- Varicella Zoster Virus
- Epstein Barr Virus
What are the three Epstein Barr Virus Related Syndromes?
- Infectious Mononucleosis
- Reactivation-related Syndromes
- Malignancies (Burkitt’s Lymphoma and Nasopharyngeal Carcinoma)
Symptoms of Infectious Mononucleosis
fatigue, pharyngitis, rash, others
What was Infectious Mononucleosis originally called?
Glandular Fever
What are heterophile antibodies?
Antibodies that react with antigens other than the antigens that stimulated their production
Heterophile antibodies in Infectious Mono patiens agglutinate what?
sheep erythrocytes
Globulin class antibody of the heterohile antibody
- IgM antibodies
Time of appearance of the heterohile antibody
- appear 6-10 days after onset
Time of disappearanceof the heterohile antibody
- disappear shortly after symptoms (6 wks to 6months)
Percentage of infectious mono cases in which the heterophiles antibody is NOT produced
- present in 80-90% of infected so NOT produced in 10-20% of infected people
- most healthy individuals do not have heterophiles antibodies
How did Paul and Bunnell contribute in the development of diagnostic tests for infectious mono?
They had a presumptive test for heterophiles antibodies:
- Direct Hemagglutination assay
Principle of Paul and Bunnell’s Direct Hemagglutination Assay
Sheep erythrocytes are mixed with serial dilutions of serum, incubated, and observed for agglutination
What is the problem with Paul and Bunnell’s Direct Hemagglutination Assay
There are other heterophiles antibodies!
- Heterophiles of the Forssman type (antibodies that also agglutinate sheep erythrocytes - we thought you could only do that if you had mono)
Heterophile antibodies of the Forssman type react with Forssman antigen which is found in the tissue of many animals for example: ______ _____
guinea pigs
What is a syndrome resulting from therapeutic administration of animal blood and serum products?
Serum Sickness
Why is serum sickness a problem for Paul and Bunnell’s direct hemagglutination assay?
Patients with serum sickness have antibodies that agglutinate sheep erythrocytes!!
Who discovered Hererophile Antibodies of serum sickness?
Davidsohn
What are the steps in the Daividsohn Differential Test (Combined Heterophile Antibody Test)?
- Take patients serum and do the presumptive test (no absorption)
- Add Guinea pig kindey to the serum which absorbs Forssman and Serum Sickness ab
- Add Beef Stroma to the serum and absorbs out the IM and Serum Sickness Ab
Guinea Pig Kidney absorbs what?
- Forssman Ab
2. Serum Sickness Ab
Beef Stroma absorbs out what?
- Infectious Mono Ab
2. Serum Sickness Ab
After using Guinea Pig Kidney absorbing antigen, you got a POS agglutination of Erythrocytes and after using Beef Stroma you got NEG agglutination.
What type of Heterophile Antibody is found?
Infectious Mononucleosis
After using Guinea Pig Kidney absorbing antigen, you got a NEG agglutination of Erythrocytes and after using Beef Stroma you got POS agglutination.
What type of Heterophile Antibody is found?
Forssman
After using Guinea Pig Kidney absorbing antigen, you got a NEG agglutination of Erythrocytes and after using Beef Stroma you got NEG agglutination.
What type of Heterophile Antibody is found?
Serum Sickness
What rapid test (1-2 min) detects heterophiles antibodies?
Contemporary Heterophiles (mono spot) Slide Test
Contemporary Heterophile (mono spot) Slide Test uses what antigen ONLY?
Guinea pig absorbing antigen
Contemporary Heterophile (mono spot) Slide Test uses what indicator particles?
erythrocyte indictor particles
Steps of the Contemporary Heterophile (mono spot) Slide Test
- Add patients serum and guinea pig kidney absorbing antigen onto a card and mix
- add erythrocytes and mix
- observe agglutination
- If agglutination: positive for Infectious Mono
Passive Latex Agglutination Methods for Detecting Heterophile Antibodies of Infectious Mononucleosis:
- What is the antigen?
- What is the antigen coated on?
- antigen is an extract of bovine red cells (includes the “mononucleosis antigen”)
- the antigen is coated on latex particles
Passive Latex Agglutination Methods for Detecting Heterophile Antibodies of Infectious Mononucleosis:
- principle
Serum from patient is mixed with the coated latex particles
- if agglutination is seen, the patient has infectious mononucleosis
Passive Latex Agglutination Methods for Detecting Heterophile Antibodies of Infectious Mononucleosis:
- what can cause a false positive reaction
Serum Sickness
What are the issues with IM tests that detect heterophiles antibodies
- too many variables
- heterophile antibodies are nonspecific
- some of IM cases (10-20%) are heterophiles negative
Epstein Barr Virus does not proliferate in standard cell cultures so antibodies to several EBC antigen are detected by _____ _____
serologic tests
What clinical situation is testing for EBV antibodies most helpful in the diagnosis of infectious mono?
EBV antibody tests are used mainly in confirming IM in heterophile negative cases
What are the three types of of Epstein-Barr virus antibodies that are known to be produced in infectious mono, and indicate what order they appear.
- EBV VCA IgM
- EBV VCA IgG
- EB EA
- EBNA
What syndrome do you have if:
- EBV VCA IgM = NEG
- EBV VCA IgG = NEG
- EB EA = NEG
- EBNA = NEG
No EBV
What syndrome do you have if:
- EBV VCA IgM = POS
- EBV VCA IgG = POS
- EB EA = POS
- EBNA = POS/NEG
Acute Infection
What syndrome do you have if:
- EBV VCA IgM = NEG
- EBV VCA IgG = POS
- EB EA = NEG
- EBNA = POS
Past Infection
What syndrome do you have if:
- EBV VCA IgM = POS/NEG
- EBV VCA IgG = POS
- EB EA = POS/NEG
- EBNA = POS
Reactivation
