Rev. Bras. Hematol. Hemoter. vol.37 número4

rev bras hematol hemoter. 2015;37(4):215–216

w w w . r b h h . o r g

Revista

Brasileira

de

Hematologia

e

Hemoterapia

Brazilian

Journal

of

Hematology

and

Hemotherapy

Scientific

Comment

ABO

isohemagglutinin

titration

or

hemolysin

test:

what

should

we

do

to

reduce

the

risk

of

passive

hemolysis?

夽

Lilian

Castilho

UniversidadeEstadualdeCampinas(Unicamp),Campinas,SP,Brazil

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Articlehistory: Received14April2015 Accepted14April2015 Availableonline18May2015

PlateletconcentratesfromABO-identicaldonorsarethe com-ponentsofchoicefortransfusions.Sinceplateletinventories aregenerallyinsufficientandbecausethereisusuallyahigher frequencyofgroupOdonors,perfectmatchesarenotalways possible and therefore ABO-incompatible platelet transfu-sionsareanacceptedpracticewhenABO-identicalplatelets are unavailable.1 _{However, an acute hemolytic transfusion}

reaction(HTR)canbeaseverecomplicationafterthis type oftransfusiondue tothe passivetransfusion ofantibodies fromdonorspossessingunusuallyhigh-titersofanti-Aand/or anti-Bantibodies.2

Reducing the risk of HTRs due to plasma-incompatible platelet transfusions hasbeen generatinginterest and dis-cussions.Strategiestoreducetheriskofplatelet-associated HTRs includevolume reduction of platelets and screening donorplasmaforhightitersofantibodiesbyperforming anti-Aand/oranti-Btitrationorassaysforinvitrohemolysis.1

Methodscurrentlyemployedtoidentifyhightitersof anti-A and/or anti-B antibodies include titration by the saline agglutination test, with and without incubation, gel test,

DOIoforiginalarticle:http://dx.doi.org/10.1016/j.bjhh.2015.05.001. 夽

SeepaperbyLandimetal.onpages217–22.

∗ _{Correspondenceto:CentrodeHematologiaeHemoterapia,UniversidadeEstadualdeCampinas(Unicamp),RuaCarlosChagas480,Barão}

Geraldo,13081-970Campinas,SP,Brazil. E-mailaddress:[email protected]

solid-phasetest,flowcytometry,automatedtechnologiesand a qualitativehemolysintest. Many countries haveadopted universal screeningwhereacriticalIgMtiterisbetween64 and100intubeorgeltests,andacriticalIgGtiterisbetween 200and512.3,4_{However,non-standardizedmethodsofIgMor}

IgGisohemagglutinintitrationandthelackofagreementof a‘criticaltiter’thatwillpredictinvivohemolysishavemade thedeterminationofABOantibodytitersdifficultandlimited toafewbloodbanks.5_{Additionally,documentationthattiter}

methodspreventHTRsisnotclear.Basedonthis,itremains unclear whethertitration isthebest ormostcost–effective approach. Currently, the use of the hemolysintest for the identificationofhemolyticanti-Aandanti-Bantibodieshas emergedasausefulscreeningtesttoidentifyhighlevelsof anti-Aand/or anti-Bantibodies andhasrecentlybeen sug-gested bythe Brazilianlegislation asprophylaxis foracute HTRs.

Regulatoryagenciesrequirethatbloodbankshaveapolicy topreventHTRsduetoplasma-incompatibleplatelet trans-fusionsbutthechoiceofthebestapproachtopredictHTRs

http://dx.doi.org/10.1016/j.bjhh.2015.04.002

216

isstillabigchallengeaslittleisknownaboutthecorrelation betweenisohemagglutinintitrationandthe hemolysintest, andtheimpactofeachtestonthepreventionofhemolysis andonplateletinventorymanagement.

Inthisissue,thereisanimportantstudyonthe correla-tionbetweenisohemagglutinintitrationandthe qualitative hemolysintestasprophylactictests topreventHTRs.6 _The

authorsevaluatedtheimpactofeachprophylaxisonplatelet inventorymanagementandtheabilityofthehemolysintest toavoidredbloodcell(RBC)sensitizationafterthetransfusion ofincompatibleunits.6 _{Inthisstudy,theydemonstratethat}

theresultsofisohemagglutinintitrationarenotrelatedtothe resultsofthehemolysinqualitativetestandtheabsenceof hemolysisdoesnotpreventRBCsensitization.Theyalso con-cludethattheimplementationofthehemolysintestasthe prophylaxisofchoiceforhemolysissignificantlyaffectsthe plateletinventorymanagement.Therefore,accordingtothe authors,isohemagglutinintitrationusingawell-standardized methoddeterminingacut-offforlabelingaproductas high-titerisstillthebestapproach.

This paper represents an additional contribution for designingand implementingpoliciestoimprove thesafety ofABO-incompatibleplatelettransfusions.Theresultsofthe studiesbyLandimetal.6_{alsoshowthatnostandardstrategy}

existstomitigateinvivohemolysisandservetostimulatea reviewofBrazilianpracticesandpoliciesfortheadvancement ofplatelettransfusionsafety.

Thefindingthatnoneofthemethods(isohemagglutinin titrationandthehemolysintest)isguaranteedtoeliminate theriskofpassivehemolysissupportstheconceptthatthere are combinations of factors influencing hemolysis due to plasma-incompatibleplatelets.3

Although HTR after ABO-incompatible platelet transfu-sionsisarare eventwewillhavetolooktofuture studies tobetterunderstandotherriskfactorsinadditiontothebest cut-offforABOplasma-incompatibletiters.

Conflicts

of

interest

Theauthordeclaresnoconflictsofinterest.

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1.QuillenK,SheldonSL,Daniel-JohnsonJA,Lee-StrokaAH,

FlegelWA.Apracticalstrategytoreducetheriskofpassive

hemolysisbyscreeningplateletpheresisdonorsforhigh-titer

ABOantibodies.Transfusion.2011;51(1):92–6.

2.JosephsonCD,MullisNC,vanDemarkC,HillyerCD.Significant

numbersofapheresis-derivedgroupOplateletunitshave

high-titeranti-A/A,B:implicationsfortransfusionpolicy.

Transfusion.2004;44(6):805–8.

3.KarafinMS,BlaggL,TobianAA,KingKE,NessPM,SavageWJ.

ABOantibodytitersarenotpredictiveofhemolyticreactions

duetoplasma-incompatibleplatelettransfusions.

Transfusion.2012;52(10):2087–93.

4.KangSJK,LimYA,BaikSY.ComparisonofABOantibodytiters

onthebasisoftheantibodydetectionmethodused.AnnLab

Med.2014;34(4):300–6.

5.CoolingLL,DownsTA,ButchSH,DavenportRD.Anti-Aand

anti-BtitersinpooledgroupOplateletsarecomparableto

apheresisplatelets.Transfusion.2008;48(10):2106–13.

6.LandimCS,GomesFC,ZezaBM,MendroneAJr,DinardoCL.

Prophylaticstrategiesforacutehemolysissecondaryto

ABO-minorincompatibleplatelets:correlationbetween

hemolysinqualitativetestandisohemagglutinintitration.Rev