ABSTRACT
PatientswithWAIHAusuallyhaveimmunoglobulinsand/orcomplementdetectableontheir redbloodcells(RBCs)bythedirectantiglobulintest(DAT).Upto10%mayhaveaweakly positiveoranegativeDAT,andmoresensitivemethodsmaybeneededtodetectthecell-bound immunoglobulins(seebelow).Table3showstheresultsoftestingRBCsfrom104patients withanti-immunoglobulins(lg)anti-IgG,anti-IgM,anti-IgA,andanti-C3(containingantiC3dg).Mostlaboratoriesuseonlyanti-lgGandanti-C3.Usingtheseantiglobulinsera(AGS) totesttheRBCsof244patientswithWAIHA,wefound67%hadRBC-boundlgGandC3; 20%hadRBC-boundIgGbutnoC3;and13%hadRBC-boundC3butnolgG(3).Sokolet al.(5)foundreversedfindingstousinthelgG+C3(24%)andIgGalone(61%)groups.This mightreflectontheamountofanti-C3dgintheanti-C3usedfortheDAT.
