HaemophilusinfluenzaetypeB(HiB)isaverycommoncauseofinvasivecriticalinfectiousdiseasesinchildrenuptotheageofsix.Followinginfectionthesymptomsofthediseaseinclude:Pericarditis,osteomyelitis,meningitis,encephalitis,pneumonia,sinusitisandotitis.Inmanycasesthediseaseislethalorleadstoneurologicaldamage,whichcannotalwaysbepreventedbyrapidantibiotictherapy.Theunderlyingreasonforthediseaseisveryoftenalatentimmunodeficiencywithaspecificallyreducedhumoralimmuneresponsetothepolyribosylribitolphosphate(PRP)inthepolysaccharideencapsulationofthebacterium.Inchildrenanotherreasonistheimmaturityoftheimmunesystem.Todayoftentheterm"immunocompromisedpatients"isused,comprisingallacquiredandinnatespecificandunspecificimmunodeficiencies.
Asaresult,inchildrenof3monthsofageorolderavaccinationwithdifferentsortsofPRP-containingvaccinesisrecommended.ThiscanleadtoaclearreductioninthenumberofinfectionswithHaemophilusinfluenzaetypeB.
Thetiterofantibodiesproducedbyvaccinationcanbeusedtoconfirmwhetherthevaccinationhasbeensuccessful.TheHiBIgGisusedtomeasurethelevelofPRP-specificIgG-antibodiesfollowinga46weekperiodaftercompleteimmunizationtomonitorthehumoralimmunestatusofchildrenorotherindividualsatrisk.
Monitoringofthehumoralimmunostatusaftervaccination.VerificationofthediagnosisHaemophilusinfluenzaetypeBinfectionbyrepeatedmonitoringofantibodyconcentrations.RiskassessmentinimmunocompromisedpatientsleADIngtoafailureofvaccinationwithaPRP-containingvaccine.
Thisgroupcomprises:
Childrenunder2yearshavinghadaninfectionwithHaemophilusinfluenzaetypeB,
Childrenwithchronic,recurringbacterialinfectionsoftherespiratorytract,
Childrenwithchronicotitis,
Patientswithconfirmedhumoralimmuno-deficiencies(IgG-2-deficiency,IgA-deficiency),
Patientswithconfirmedgranulocytedeficiencies,
Patientsunderchemoorcytostatictherapy,
Childrenaftersplenectomy,
Patientswithsickle-cellanaemia,
Patientswithtrisomy21(Down)syndrome,andcertainethnicgroups.