G GM试验 真菌检测ppt课件

G试验和GM试验-真菌检测,马桂伶2011-3-16,1,真菌感染会带来怎样的后果呢？,Mortality,lengthofhospitalization,andcostsassociatedwithinvasivefungalinfectionsinhigh-riskpatients.MenzinJ,MeyersJL,FriedmanM,PerfectJR,LangstonAA,DannaRP,PapadopoulosG.AmJHealthSystPharm.2009Oct1;66(19):1711-7.,3,4,5,6,7,8,9,G试验和GM试验-真菌检测,马桂伶2011-3-16,10,深部真菌,白色念珠菌新型隐球菌曲霉菌毛霉菌,11,传统的检测方法主要为血培养和组织活检，但血培养历时太长，且阳性率较低。近年来，用于检则真菌的抗原、抗体及代谢产物的血清学检查已用于深部真菌感染的实验室检测。目前的血清学检查主要针对真菌胞壁或胞内成分beta-葡聚糖、甘露糖、烯醇化酶和Cand-Tec抗原等。,12,G试验-（1，3）-D葡聚糖试验,G试验检测的是真菌细胞壁成分(1，3)-D葡聚糖，由于(1，3)-D-葡聚糖仅广泛存在于真菌的细胞壁中，当真菌进入人体血液或深部组织后，经吞噬细胞的吞噬、消化等处理后，(1，3)-D-葡聚糖可从胞壁中释放出来，从而使血液及其它体液中(1，3)-D-葡聚糖含量增高。当真菌在体内含量减少时，机体免疫可迅速清除(1，3)-D-葡聚糖。在浅部真菌感染中，(1，3)-D-葡聚糖未被释放出来，故其在体液中的量不增高。,13,20世纪90年代初发现,(1-3)-beta-D-葡聚糖可特异性激活自鲎变形细胞溶解产物提取的G因子,从而旁路激活鲎试验,此过程称为G试验。临床上,由于深部真菌感染的严重程度常常与血浆多糖的升高水平一致,故G试验可协助深部真菌感染的诊断(包括念珠菌感染和曲霉菌感染等)。,14,GM实验-半乳甘露聚糖试验,甘露糖是目前研究最为广泛的一种抗原,广泛存在于真菌胞壁中,是真菌胞壁的重要组成成分.,15,Plasma(1-3)-beta-Dglucanmeasurementindiagnosisofinvasivedeepmycosisandfungalfebileepisodes,目的：探讨(1-3)-beta-Dglucan在筛查侵袭性真菌感染及真菌性发热中的价值。方法：检测了202例病员标本，以(1-3)-beta-D-葡聚糖的血浆浓度20pg/ml为界值,41例确诊病员(以活检和培养阳性为标准)，37例为阳性,阳性率为90%;59例其他原因所致发热者全部阴性,阴性率为100%结论：(1-3)-beta-D-葡聚糖可用于早期诊断深部真菌感染,其缺点是不能定性,且此法不能检测出隐球菌感染,可能是因为隐球菌具有厚壁胞膜。,ObayashiT,YoshidaM,MoriT,etal.Plasma(1，3)-beta-DglucanmeasurementindiagnosisofinvasivedeepmycosisandfungalfebileepisodesJ.Lancet,1995,345(1):17-20.,16,17,KarageorgopoulosDM,b-D-GlucanAssayfortheDiagnosisofInvasiveFungalInfections:AMeta-analysis,ClinicalInfectiousDiseases.2011;52(6):75077,18,76.8%,85.3%,19,conclusion,BDGhasgooddiagnosticaccuracyfordistinguishingprovenorprobableIFIsfromnoIFIs.Itcanbeusefulinclinicalpractice,ifimplementedinthepropersetting.,20,Toupdatethecase-fatalityrate(CFR)associatedwithinvasiveaspergillosisaccordingtounderlyingconditions,siteofinfection,andantifungaltherapy,dataweresystematicallyreviewedandpooledfromclinicaltrials,cohortorcase-controlstudies,andcaseseriesof10patientswithdefiniteorprobableaspergillosis.Subjectswere1941patientsdescribedinstudiespublishedafter1995thatprovidedsufficientoutcomedata;casesincludedwereidentifiedbyMEDLINEandEMBASEsearches.ThemainoutcomemeasurewastheCFR.Fiftyof222studiesmettheinclusioncriteria.TheoverallCFRwas58%,andtheCFRwashighestforbonemarrowtransplantrecipients(86.7%).AmphotericinBdeoxycholateandlipidformulationsofamphotericinBfailedtopreventdeathinone-halftotwo-thirdsofpatients.MortalityishighdespiteimprovementsindiagnosisanddespitetheadventofnewerformulationsofamphotericinB.Underlyingpatientconditionsandthesiteofinfectionremainimportantprognosticfactors.,LinSJ,SchranzJ,TeutschSM.Aspergillosiscase-fatalityrate:systematicreviewoftheliterature.ClinInfectDis.2001;32:358366.,21,ChristopherD,DiagnosisofInvasiveAspergillosisUsingaGalactomannanAssay:AMeta-Analysis,ClinicalInfectiousDiseases2006;42:141727,22,23,0,0.93,0.0.71,0.61,00.89,24,Conclusions,GMtesthasmoderateaccuracyfordiagnosisofinvasiveaspergillosisinimmunocompromisedpatients.Thetestismoreusefulinpatientswhohavehematologicalmalignancyorwhohaveundergonehematopoieticcelltransplantation,25,GM试验在非血液病患者真菌检测中的应用,26,27,28,29,conclusion,1TheprevalenceofinvasiveaspergillosisinthegroupofpatientswithCOPDwas16.13%。2The1ng/mlcut-offshowedahigherpositivepredictivevalue(100%)andcomparablenegativepredictivevaluetothe0.5ng/mlcut-off.ThevalueofthetestinCOPDpatientsyieldedsimilarresults.,30,COPDpatientsmayhaveincreasedsusceptibilitytofungalinvasiveinfectionforseveralreasons,(1)structuralchangesinlungarchitecturerelatedtothepulmonarydisease;(2)thecommonuseoflong-termorrepeatedshort-termsteroidtreatmentsasanadditionalimmunosuppressivefactor;(3)frequenthospitalisationandantibiotictreatment,leadingtoexposuretoselectedfungalpathogens;(4)co-morbidityfactorssuchasalcoholism,diabetesmellitusormalnutrition.,F.Ader.Invasivepulmonaryaspergillosisinchronicobstructivepulmonarydisease:anemergingfungalpathogen.ClinMicrobiolInfect,2005;11:427429,31,GM试验在COPD合并真菌感染诊断中的应用,32,33,34,conclusion,InCOPDpatients,invasivepulmonaryaspergillosiscurrentlycarriesaverypoorprognosis.Outcomecouldperhapsbeimprovedbymorerapiddiagnosisandprompttherapywithvoriconazole.,35,重度COPD患者合并侵袭性曲霉菌病的结果？,36,37,38,E,39,GMtestresult,40,GMtestandmortality,41,GroupMortality,AllpatientsIPAgroupnon-IPAgroupAspergillusisolated,33.3%(30/90),73.7%(14/19),22.5%(16/71),70.0%(14/20).,42,conclusion,1TheincidenceofIPAintheCOPDpatientsadmittedtotheICUwas11.1%(19/171)2serumGMshouldbetestedatleasttwiceaweektoachieveearlydiagnosisofaspergillosis.3atleastonepositiveresultoftwoconsecutiveGMtestsappearstobeusefulinthediagnosisofIPAincriticallyillCOPDpatientsinanICU.4positiveserumGMresultscombinedwiththeisolationofAspergillusfromrespiratorysamplesmaybeapotentialmarkerofhighmortality.,43,GGM试验的联合应用,44,45,RepresentativekineticsofBG()andGM()indifferentpatients.(a)ProvenIAinapatientwithacutemyeloidleukemiawhorespondedtotreatmentwithamphotericinBandcaspofungin.,46,(b)ProvenIAinapatientwithchroniclymphocyticleukemiawhodidnotrespondtotreatmentwithamphotericinB.,47,(c)False-positiveBGresultsinapatientwithmultiplemyelomaandnoIA.,48,(d)False-positiveGMresultsinapatientwithnon-HodgkinslymphomaandnoIA.,49,(e)NegativeBGandGMresultsinapatientwithacutemyeloidleukemiaandnoIAwhowascolonizedbyC.albicansandC.glabrata.,50,(f)NegativeBGandGMresultsinapatientwithchroniclymphocyticleukemiaandnoIAwhowascolonizedbyC.albicans,51,conclusion,1Thesensitivity,specicity,andpositiveandnegativepredictivevaluesforGMandBGwereidentical,87.5,89.6,70,and96.3%2False-positivereactionsoccurredatarateof10.3%inbothtests,butthepatientsshowingfalse-positiveresultsweredifferentineachtest.Bothtestsanticipatedtheclinicaldiagnosis,computedtomographyabnormalities,andtheinitiationofantifungaltherapyinmostpatients,butBGtendedtobecomepositiveearlierthanGM.3Acombinationofthetwotestsimprovedthespecicity(to100%)andpositivepredictivevalue(to100%)ofeachindividualtestwithoutaffectingthesensitivityandnegativepredictivevalues.BGandGMdetectionareusefultestsforthediagnosisofIAinhigh-riskhematologicalpatients,andthecombinationofthetwotestswasveryusefultoidentifyfalse-positivereactionsbyeachtest.,52,总之：G、GM试验都可用于侵袭性真菌感染的检测，G试验对念珠菌及曲霉菌都有较好的敏感度，但不能区分出是念珠菌还是曲霉菌感染；GM试验对曲霉菌感染有较好的特异度。联合GGM试验对临床诊断侵袭性曲霉菌病有较好的价值，但这两个试验用于隐球菌检测，缺乏临床证据，GM试验能否用于念珠菌的检测仍不明确。,53,感谢聆听不妥之处，望批评指正,54,55,Diagnosis,ProveninvasiveFIProbableinvasiveFIPossibleinvasiveFI,Histopathologicorcytopathologicexaminationshowinghyphaefromneedleaspirationorbiopsyspecimenwithevidenceofassociatedtissuedamage;orpositivecultureresultforasampleobtainedbysterileprocedurefromnormallysterileandclinicallyorradiologicallyabnormalsiteconsistentwithinfectionAtleast1hostfactorcriterion;1microbiologicalcriterion;and1major(or2minor)clinicalcriteriafromabnormalsiteconsistentwithinfectionAtleast1hostfactorcriterionand1microbiologicalor1major(or2minor)clinicalcriteriafromabnormalsiteconsistent,56,Typeofdiagnosticcriteria-hostfactors,1Neutropenia(96hrefractorytoappropriatebroad-spectrumantibacterialtreatmentinhigh-riskpatients;3bodytemperatureeither38Cor36Candanyofthefollowingpredisposingconditions:prolongedneutropenia(110days)inprevious60days,recentorcurrentuseofsignicantimmunosuppressiveagentsinprevious30days,provenorprobableinvasiveFIduringpreviousepisodeofneutropenia,coexistenceofsymptomaticAIDS;signsandsymptomsindicatinggraft-versus-hostdisease,particularlysevere(grade2)orchronicextensivedisease;prolonged(13weeks)useofcorticosteroidsinprevious60days.,57,Typeofdiagnosticcriteria-Microbiologicalcriterion,1Po