侵袭性深部真菌病的实验室诊断课件

侵袭性深部真菌病的实验室诊断临床微生物科侵袭性真菌病的致病菌—条件致病菌—致病性双相真菌念珠菌组织胞浆菌曲霉球孢子菌隐球菌芽生菌接合菌马内菲青霉镰刀菌孢子丝菌暗色真菌酵母菌毛孢子菌枝顶孢霉侵袭性真菌病(IFD)主要包括：念珠菌病隐球菌病侵袭性曲霉病IFD的高危人群和高危因素广谱抗生素应用入住ICU血液系统肿瘤病人（粒缺、骨髓移植）器官移植HIV感染应用皮质激素糖尿病静脉插管尸体解剖中侵袭性真菌感染的发生率78798081828384858687888990919202468Aspergillusspp.Candida

spp.AllotherPrevalenceatAutopsy[%]PrevalenceofinvasiveaspergillosisatnecropsyatJWGeotheUniversityHospital,Frankfurt,Germany(Lancet,2000;335:2076)54.84%12.9%3.23%9.68%19.35%国内西南医院尸解资料，(1971-2000)，郝飞教授提供AspergillusCryptococcusMucorCandidaAllothers真菌感染的实验诊断方法及问题形态学检查：经验？阳性率？培养+鉴定：时间长，敏感性？血清学检查：敏感性？特异性？分子生物学检查：标准化？新生隐球菌乳胶凝集试验在BAL中检测GM作为早期诊断标志Musheretal.JClinMicrobiol2004:42(12):5517-22敏感性(%)特异性(%)阳性预测(%)阴性预测(%)血清47937382BAL8510010088Beckeretal.BrJHaematol2003;121:448关于GM试验与G试验可作为推定诊断的标准;GM:

检测半乳甘露聚糖，对曲霉感染诊断特异性强，假阳性反应可以在青霉菌属中出现；部分含青霉烷砜衍生物的抗菌药物可以诱发阳性反应；G试验:

检测(1,3)-ß-D-葡聚糖，在很多真菌中都可以出现阳性反应，但在隐球菌、接合菌、毛霉、根霉呈阴性反应；Prospectiveutilityof(1-3)-B-D-Glucan(BG),galactomannan(GM)andanti-Candidaalbicansgermtubeantibodies(CAGT)forthediagnosisofinvasivefungaldisease(IFD)inhaemato-oncologyadultpatientsA.Alhambra1,M.S.Cuétara2,J.M.Moreno1,A.DelPalcioPerez-Medel1,I.Moragues3,J.Pontón3,A.DelPalacio11HospitalUniversitarioDocedeOctubre,MADRID,Spain2HospitalUniversitarioSeveroOchoa,LEGANES,Spain3UniversidaddelPaisVasco,BILBAO,SpainInvasiveCandidiasisSSPPPVNPVCAGT(%)57934496BG(%)77863997InvasiveAspergillosisSSPPPVNPVGM(%)92947398BG(%)57844291CONCLUSIONSTheincidenceofIFDcorrelateddirectlyandsignificantly(x2p=0.0005)withriskstratificationgroup:highestproportioninthehigh-riskgroup.Sinceallthebiomarkershaveinherentlimitations,abetterdiagnosisyieldisachievedcombiningthebiomarkers.AllthreebiomarkerssharehighnegativepredictivevalueandcanexcludereasonablyIFDinhaematologyadultpatientstreatedwithwidespectrumantifungals.Atotalof236serafrom51patientsinriskofIAweretestedforGMusingPlatelia

Aspergilluskit(BioRad,France)which36sera(10patients)weretestedforBGalsousingFungitellkit(AssociatesofCapeCod.,USA).PatientswereattendedattheUniversityHospitalofValmefromSevillefromJanuaryof2008toDecember2008.PatientswithGMindex≥0.5intwoconsecutivesampleshavebeenmarkedasGMpositiveandsampleswithresults≥80pg/mlweremarkedasBGpositive.AllGMpositivepatientswereclassifiedaccordingtoEORTC/MSGcriteria(2008)forprobabilityofIA.GMtestFrom51patientstudied,16ofthemshowedatleastonepositivespecimen(33sera).Only6patientsshowedtwoconsecutivepositiveresults(≥0.5GMtest)andtheyshowclinicalsignsormicrobiologicalcriteriaforAIproven(3patients)andprobable(3patients).ConclusionCalculatingsignificantsensitivityforbothdetectionmethodswasnotfeasibleduetoalownumberofproven/probableAI.BGdetectionshowedpositiveresultsbeforeGMtestandpresentthegreatadvantagetobea“panfungal”antigen.BGdetectionshouldbeusedwithothertechniquesfordetectionofinvasiveAspergillosisinfections.真菌细胞壁结构示意图检测结果正常对照组血浆1-3-β-D葡聚糖含量最高为7.29pg/ml，最低为0.45pg/ml，平均值为2.83±2.57pg/ml；深部真菌感染组血浆1-3-β-D葡聚糖含量最高为168.9pg/ml，最低为14.93pg/ml，平均值为54.06±36.13pg/ml。经SPSS统计软件T-检验分析，对照组与深部真菌感染组1-3-β-D葡聚糖平均值差异非常显著（t=7.741,P＜0.001）。讨论入选的深部真菌感染患者均经细菌培养证实为念珠菌感染，包括白色念珠菌23株、热带念珠菌8株、季也蒙念珠菌1株、克柔念珠菌1株和光滑球拟假丝酵母菌2株，无隐球菌感染。如以10pg/ml为cutoff值，则阳性率为100%;以20pg/ml为cutoff值，则阳性率为91.4％。葡聚糖检测可在拟诊早期为临床医生提供机体是否感染真菌的可靠信息，因此葡聚糖含量检测不失为一种实用的真菌感染早期诊断方法。注意使用青霉素类加酶抑制剂香菇多糖等会引起假阳性！122patients–323samples–33provencasesTimeAxisofMethodsforDetectionofPulmonaryAspergillosisCTpositive123456789101112131415chestX-rayantigenß-glucanculturehistologyPCRKamiMetal,ClinI