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Right after the prom a 18 y/o boy presnt to you with fever, malaise, swollen cervical lymph nodes, hepatosplenomegaly and sore throat.

Serum samples from the patient reveals;

-Agglutinate sheep erythrocytes
-Absent/agglutinate in guinea pig erythrocytes


Which serologic profile would most likely seen @ this time pat?

-------IgM Anti-VCA-------IgG Anti VCA----------Anit-MA-----Anti-EBNA

a)----------POS------------------POS----------------POS----------POS
b)----------NEG -----------------POS----------------NEG----------POS
c)----------POS------------------POS----------------NEG----------POS
d)----------NEG------------------POS----------------POS----------POS
e)----------POS------------------NEG----------------NEG----------NEG

AA

@proofdoc Hello! http://i.imgur.com/B7yksyS.png?1

sarah?

The patient has infectious mononucleosis (caused by EBV). hE'S ACUTELY ILL, SO IgM VCA is expected to be positive. The question does not say if he has been exposed or infrected in the past but over 90% of the population have IgG antibodies to both VCA and EBNA, so both are expected to be positive...

Honestly cardio, i dont know where anti MA comes in, so i guess its safer to choose C instead?

Can u please tell the full form of all the above mentioned antibodies?VCA, MA, EBNA?

@reminemi.... VCA: Viral capsid antigen, EBNA: Epstin Barr Nuclear Antigen, MA: Membrane Antigens

Thank @proofdoc for your help.

Ans *D*

EBNAs^/EBV nuclear Ags : -> Anti EBNA dev AFTER resolution of infection
EA-D/Early Anti EA-D: diffuse in nucleus & cytoplasmic -> Anti-EA-D seen mono infction
VCA/Viral capsid Ag: Cytoplasmic -> *anti-VCA IgM is transient ; anti-VCA IgG persistent
MA/Membrane: Ag cell surface ( envelope glycoproteins) -> same as VCA

POS for MA & VCA -> dev @ same time during the course of dz. IgM -> VCA may also POS, However the Ab to EBNAs^ ↑ during convalescence.

So cardio, the IgM anti- VCA will be negative in this patient?...thats very difficult to swallow........