Lymphoproliferative DisordersEpstein-Barr Virus InfectionsHerpesvirus 4, HumanOrgan TransplantationKidney TransplantationAutoimmune Lymphoproliferative SyndromeImmunosuppressive AgentsTransplantationTransplantation, HomologousLymphomaHematopoietic Stem Cell TransplantationLymphoma, B-CellB-LymphocytesGraft SurvivalBone Marrow TransplantationLeukemia, Hairy CellHerpesviridae InfectionsGraft RejectionPostoperative ComplicationsLymphomatoid GranulomatosisGiant Lymph Node HyperplasiaLeukemia, Lymphocytic, Chronic, B-CellImmunosuppressionTransplantsLiver TransplantationGraft vs Host DiseaseLymphoma, T-CellT-LymphocytesImmunophenotypingTime FactorsRetrospective StudiesTransplantation ConditioningAntibodies, Monoclonal, Murine-DerivedTreatment OutcomeLymphocytosisImmunocompromised HostHistocompatibility TestingHematologic NeoplasmsLymphomatoid PapulosisInfectious MononucleosisTumor Virus InfectionsTissue DonorsAntigens, CD30Leukemia, ProlymphocyticLeukemia, Large Granular LymphocyticLymphoma, Non-HodgkinLung TransplantationHodgkin DiseaseFatal OutcomeHeart TransplantationLeukemia, LymphoidLymphatic DiseasesTransplantation, AutologousPseudolymphomaEpstein-Barr Virus Nuclear AntigensLymphocytesWaldenstrom MacroglobulinemiaLymphoma, T-Cell, CutaneousAntibodies, MonoclonalAutoimmune DiseasesSplenomegalyLymph NodesBurkitt LymphomaAntigens, CDLeukemia, B-CellFlow CytometryGammaherpesvirinaeLymphocyte ActivationAllograftsDNA, ViralImmunologic Deficiency SyndromesCladribinePolymerase Chain ReactionCryoglobulinemiaLeukemia, T-CellParaproteinemiasViral Matrix ProteinsAntigens, CD20Lymphocyte TransfusionClone CellsMycosis FungoidesImmunoglobulinsRecurrenceAntigens, CD95Immunoblastic LymphadenopathyLeukemiaHerpesvirus 8, HumanIntracellular Signaling Peptides and ProteinsViral LoadAntigens, CD3Killer Cells, NaturalGenetic Diseases, X-LinkedLymphohistiocytosis, HemophagocyticHeart-Lung TransplantationFollow-Up StudiesPancreas TransplantationAntigens, CD5BiopsyVirus ActivationAngioedema