viral serology (EBV) Flashcards
diagnosis
- Indirect Hemagglutination ≥ (1:256)
- EIA (+)
E. histolytica
diagnosis
- ASO (≥ 1:240)
- Anti-DNAse B (≥ 1:240)
- Anti-Hyaluronidase (≥ 1:512)
S. pyogenes
diagnosis
- Immunodiffusion (+)
- Latex Particle Agglutination (≥ 1:80)
Candida sp.
diagnosis
- Cold Agglutinins ≥ 1:128
- Complement Fixation ≥ 1:32
- EIA (+)
M. pneumoniae
can distinguish heterophile sheep cell agglutinins in human serum caused by IM, serum sickness, and Forssman antigen.
davidsohn differential test
- principle: absorption-hemeagglutination
- exposure of test serum to both beef and guinea pig cells which causes absorption of either one or both of these antibodies
- guinea pig cells and beef rbcs
- heterophil Abs in patient’s serum
- indicator cells: sheep rbcs
- the “absorbed agglutinins” (precipitates) are removed by centrifugation and the resultant fluid (supernatant) are then tested with sheep rbc
davidsohn differential test
are stimulated by one antigen and will react with unrelated antigens from different mammalian species.
heterophile antibodies
diagnosis
- Immunodiffusion (+)
- Complement Fixation (≥ 1:32)
- Aspergillus sp.
- H. capsulatum
reacts with sheep, ox (beef), horse and guinea pig cells
heterophil antibodies in serum sickness
most useful marker for acute IM
IgM anti-VCA
diagnosis
- Indirect IFA ≥ 1:64
- EIA (+)
- Western Blot IgG ≥ 4 of 9 bands
- Western Blot IgM ≥ 2 of 9 bands
B. burgdorferi
diagnosis
- Indirect IFA (≥ 1:64)
- EIA (+)
- EA-D is also found in the (?).
- IgG antibodies to EA-D can be indicators of (?).
- IgG antibodies to EA-R are sometimes seen in young children who have active (?), but not in infected young adults.
- nucleus
- active disease
- IM infection
present at the onset of IM, persist for life (which indicates past infection)
IgG anti-VCA
Causative agent of: Burkitt’s Lymphoma, Nasopharyngealcarcinoma, Infectious Mononucleosis (IM)
EBV
diagnosis
- Indirect Hemagglutination ≥ (1:128)
- EIA (+)
Cystercosis
diagnosis
EIA (+)
H. pylori
- is an acute, self-limiting disease typically seen in young adults.
- The disease is characterized by fever, sore throat, cervical lymphadenopathy, splenomegaly, and mild hepatitis.
- The WBC count is elevated, and reactive lymphocytes are seen in the peripheral blood.
- There is a relative and absolute lymphocytosis.
- The average incubation period is approximately 2 to 8 weeks
infectious mononucleosis (IM)
used for any substance that stimulated the formation of sheep hemolysin (anti-sheep cells)
forssman antigen
diagnosis
- RPR (+)
- VDRL (+)
- FTA-ABS (+)
T. pallidum
diagnosis
- Immunodiffusion (+)
- EIA (≥ 1:32)
B. dermatitidis
- reacts with sheep cells, ox (beef) cells and horse cells but not with guinea pig cells
- not forssman in nature
heterophil antibodies in IM
diagnosis
Indirect IFA (≥ 1:64)
- R. rickettsi
- E. chaffeensis
diagnosis
Indirect IFA (≥ 1:128)
B. henselae
(?) antibodies to EBNA develop slowly but can remain detectable throughout life.
IgG
- The heterophile antibodies of IM are (?) antibodies and are seen in 50% to 70% of patients with IM.
- They persist for (?) to (?) weeks after infection.
- IgM
- 4, 8
- guinea pig cells are injected into rabbits» Ab fotmation
- Abs formed: anti-guinea pig cells and anti-sheep cells
forssman
- principle: absorption-hemeagglutination
- guniea pig, kidney cells, and beef rbcs
- heterophil Abs in patient’s serum
- indicator cells: horse rbcs
- same patterns with davidson
monospot
diagnosis
Indirect IFA (≥ 1:256)
L. pneumophila
based on the principle that horse RBCs are agglutinated by the heterophile antibodies of IM.
monospot test
- principle: hemeagglutination
- presumptive/screening test
- incapable of determining specificity and is only indicative of the presence or absence of heterophil Abs
- 2% suspension of sheep rbcs
- heterophil Abs in patient’s serum
- (+) result: hemaggln = presence of heterophil Abs
paul bunnel test
- The virus is ubiquitous; 80% to 90% of healthy (?) have EBV antibodies.
- EBV infects (?)
- adults
- B lymphocytes
- (?) antibodies against VCA are detectable early in the infections, but disappear within (?) to (?) months.
- (?) antibodies against VCA develop within (?) week after infection and can persist for life.
- IgM
- 2, 4
- IgG
- 1
diagnosis
- Bentonite Flocculation (≥ 1:5)
- EIA (+)
T. spira
reacts with guinea pig cells, horse and sheep cells but not with beef cells
heterophil antibodies of forssman
antibodies produced by unrelated species which can cross-react with the same antigen
heterophil antibodies
appears during convalescence
anti-EBA
diagnosis
EIA (≥ 1:32)
Toxocara sp.
found in the nuclei of all infected cells.
EBNA (epstein-barr nuclear antigen)
diagnosis
Widal Test (≥ 1:160)
S. typhi
- Can detect only the presence or absence of heterophile antibodies.
- It cannot determine the specificity of the antibodies
paul-bunnell test
seen also in acute IMS
anti-EAD
are found in the cytoplasm of infected B lymphocytes.
- EA-D (early antigen-diffuse)
- EA-R (early antigen-restricted)
found in the cytoplasm of EBV infected lymphocytes.
VCA (viral capsid antigen)
