InfectiousmononucleosisisanacutelymphoproliferativediseasethatiscommoninchildrenandyoungadultsandiscausedbytheEpstein-Barrvirus.TheEBVisoneoftheherpesviruses4(gamma).
Characteristicclinicalfeaturesinclude:
1.fever,sorethroat,andlymhadenopathy,
2.anassociatedabsolutelymphocytosisgreaterthan50%containingatleast10%ofatypicallymphocytesintheperipheralblood,
3.developmentoftransientheterophilandpersistentantibodyresponsesagainstEBV,
4.andabnormalliverfunctiontests.
4%ofinfectedyoungadultsshowanictericmanifestationand50%havesplenomegaly.Inaddition,EBVisimplicatedinBurkittlymphoma,nasopharyngealcarcinomaandHodgkin´sdisease.
Asyndromesimilartoinfectiousmononucleosiscanbecausedbycytomegalovirus,toxoplasmosisandotherviralinfections.Thereforethedifferentialdiagnosisisofmajorimportance.SEROlogicaltestslikeEIAareveryusefulforthedetectionofanti-EBVIgGandIgMantibodies,especiallyincaseswhereheterophilantibodiesareabsent.InafreshinfectionIgMantibodiesagainstVCAandEAaredeterminedbyimmunofluorescenceorELISA.LateronVCAIgGappearfollowedbyEBNA-1IgGantibodies.CorrespondinglythesimultaneousactivationofVCAIgMandEBNA-1IgGindicatesareactivationofanEBVinfection.TheIBLEBV(EA)IgGELISAishelpfultomonitorconvalescenceandreactivatedinfectionsaswellasthedetectionofthenasopharynxcarcinomaandBurkittLymphoma.ImmuneresponsestothenasopharynxcarcinomaandchronicreactivatedEBVinfectionscanbecharacterizedwiththehelpoftheIBLEBV(EA)IgAELISA.