LuminescenceImmunoassayforthein-vitro-diagnosticquantitativedeterminationofimmunoreactivetrypsin
(IRT)inhumannewbornbloodspotsamples.
Forneonatalscreeningofcysticfibrosis(CF).

Cysticfibrosis(CF)isoneofthemostcommonautosomalrecessivediseasescausedbymutationsintheCFtransmembraneconductanceregulatorgene(CFTR).CFcanresultindeathatanearlyage,primarilyfromprogressivelungdisease,althoughanumberoforgansareofteninvolved.CFoccursatanincidenceofapproximately1:2000-1:5000livebirthsinEuropeandNorthAmerica.ThefirstEuropeanexperiencesincysticfibrosis(CF)newbornscreening(NBS)datebacktotheearlynineteenseventies,withpioneeringprogrammesexaminingthealbumincontentofmeconium.TheelevationofImmunoreactiveTrypsin(IRT)inthebloodofneonateswithCFanditsmeasurementindriedbloodspotswasfirstdescribedin1979.Duringthefollowingdecade,thedeterminationofIRTlevelsinheelbloodwasintroducedinseveralcountries.FurtherimprovementwaspossIBLeaftercloningoftheCFTRgenein1989andsubsequentidentificationofcommonpopulationspecificCFTRgenemutationsallowedinclusionofDNAtestingintoscreeningprotocols.StudieshaveshownthatearlydiagnosisofCFthroughneonatalscreening,combinedwithaggressivenutritionaltherapy,cansignificantlyenhancelong-termnutritionalstatus.ThetwomostcommonprotocolsforCFscreeningare(a)measuringIRTononesampleandthenonasecondsample,and(b)IRTtestingfollowedbyDNAmutationanalysisonthesamesample.