G试验和GM试验真菌检测PPT课件.ppt

G试验和GM试验 真菌检测 1 真菌感染会带来怎样的后果呢 2 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 Dglucanmeasurementindiagnosisofinvasivedeepmycosisandfungalfebileepisodes J Lancet 1995 345 1 17 20 16 17 KarageorgopoulosDM b D GlucanAssayfortheDiagnosisofInvasiveFungalInfections AMeta analysis ClinicalInfectiousDiseases 2011 52 6 750 77 18 76 8 85 3 19 conclusion BDGhasgooddiagnosticaccuracyfordistinguishingprovenorprobableIFIsfromnoIFIs Itcanbeusefulinclinicalpractice ifimplementedinthepropersetting 20 Toupdatethecase fatalityrate CFR associatedwithinvasiveaspergillosisaccordingtounderlyingconditions siteofinfection andantifungaltherapy dataweresystematicallyreviewedandpooledfromclinicaltrials cohortorcase controlstudies andcaseseriesof 10patientswithdefiniteorprobableaspergillosis Subjectswere1941patientsdescribedinstudiespublishedafter1995thatprovidedsufficientoutcomedata casesincludedwereidentifiedbyMEDLINEandEMBASEsearches ThemainoutcomemeasurewastheCFR Fiftyof222studiesmettheinclusioncriteria TheoverallCFRwas58 andtheCFRwashighestforbonemarrowtransplantrecipients 86 7 AmphotericinBdeoxycholateandlipidformulationsofamphotericinBfailedtopreventdeathinone halftotwo thirdsofpatients MortalityishighdespiteimprovementsindiagnosisanddespitetheadventofnewerformulationsofamphotericinB Underlyingpatientconditionsandthesiteofinfectionremainimportantprognosticfactors LinSJ SchranzJ TeutschSM Aspergillosiscase fatalityrate systematicreviewoftheliterature ClinInfectDis 2001 32 358 366 21 ChristopherD DiagnosisofInvasiveAspergillosisUsingaGalactomannanAssay AMeta Analysis ClinicalInfectiousDiseases2006 42 1417 27 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 11 427 429 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 Hodgkin slymphomaandnoIA 49 e NegativeBGandGMresultsinapatientwithacutemyeloidleukemiaandnoIAwhowascolonizedbyC albicansandC glabrata 50 f NegativeBGandGMresultsinapatientwithchroniclymphocyticleukemiaandnoIAwhowascolonizedbyC albicans 51 conclusion 1Thesensitivity speci city andpositiveandnegativepredictivevaluesforGMandBGwereidentical 87 5 89 6 70 and96 3 2False positivereactionsoccurredatarateof10 3 inbothtests butthepatientsshowingfalse positiveresultsweredifferentineachtest Bothtestsanticipatedtheclinicaldiagnosis computedtomographyabnormalities andtheinitiationofantifungaltherapyinmostpatients butBGtendedtobecomepositiveearlierthanGM 3Acombinationofthetwotestsimprovedthespeci city 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 3bodytemperatureeither 38Cor 36Candanyofthefollowingpredisposingconditions prolongedneutropenia 110days inprevious60days recentorcurrentuseofsigni cantimmunosuppressiveagentsinprevious30days provenorprobableinvasiveFIduringpreviousepisodeofneutropenia coexistenceofsymptomaticAIDS signsandsymptomsindicatinggraft versus hostdisease particularlysevere grade2 orchronicextensivedisease prolonged 13weeks useofcorticosteroidsinprevious60days 57 Typeofdiagnosticcriteria Microbiologicalcriterion 1Positiveresultofcu