【医学课件】感染性心内膜炎.ppt

Update onInfective EndocarditisLarry Baddour,MDUniversity of Tennessee天马行空官方博客：http:/ of the endocardial layer as a complication of abnormal blood flow associated with underlying cardiac defectBacterium-endothelium interaction with bacterial attachment and invasion of endothelial cells天马行空官方博客：http:/ valvular abnormality predisposing to infective endocarditisrheumatic fevera common cause in the pastmitral valve prolapsecurrently represents the most common underlying cardiac abnormality7/mitral valve prolapserisk for infective ednocarditis is 5x-8x mitral regurgitation increases the riskleaflet redundancy with myxomatous degeneration is a frequent findingage 20,male accounts for 60%age 50,male accounts for 68%7/Mitral Valve Prolapse and Infective EndocarditisMaleFemaleNumber of casesRev Infect Dis 1986;8:117-1377/Coagulase-negative Staphylococcican produce native-valve endocarditis in mitral valve prolapseusually subacute,difficult to diagnose,and disregarded as a contaminantdelay in diagnosis and treatment may account for the severe complicationsmyocardial abscess formationvalvular insufficiency requiring valve surgerydeath7/Prosthetic Heart Valvepositive blood culture in hospitalized patients with underlying prosthetic valves can be a harbinger of endocarditis 43%patients with nosocomial bacteremia or fungemia had prosthetic valve infectiona serious complication7/IV Drug UseRecurrentPolymicrobialStaph aureus accounts for the majority of cases of endocarditistricuspid valve,either alone or in combination,us most often infected7/Predisposing Factors Polymicrobial Infective Endocarditis 7/Polymicrobial Infective Endocarditisclinical featuresIV drug use is the predominant risk factoryounger age(mean 36.5 years)2/3 were maleright-sided cardiac involvement in 60%streptococci more frequent than S.aureus1/3 of patients died mortality rate is 4x higher for pure left-sides vs pure right-sided endocarditis7/Diagnostic(Duke)CriteriaDefinitive infective endocarditispathologic criteriamicroorganisms or pathologic lesions:demonstrated by culture or histology in a vegetation,or in a vegetation that has embolized,or in an intracardiac abscessclinical criteria(see below)two major criteria,or one major and three minor criteria,or five minor criteria7/Diagnostic(Duke)CriteriaPossible infective endocarditisfindings consistent of IE that fall short of“definite”,but not“rejected”Rejectedfirm alternate Dx for manifestation of IEresolution ofmanifestations of IE,with antibiotic therapy for 4 daysno pathologic evidence of IE at surgery or autopsy,after antibiotic therapy for 4 days 7/Diagnostic(Duke)CriteriaMajor criteriapositive blood culture for IEevidence of endocardial involvementMinor criteriapredisposition(heart condition or IV drug use)fever of 100.40F or highervascular or immunologic phenomenamicrobiologic or echocardiographic evidence not meeting major criteria7/Dukes Major Criteriapositive blood culture for IEtypical microorganism(strep viridans,strep bovis,HACEK group,staph aureus or enterococci in the absence of a primary locus)for endocarditis from two separate blood culturespersistently positive blood culture from:blood cultures drawn more than 12 hr apart,orall of 3 or a majority of 4 or more separate blood cultures,with first and last drqwn at least 1 hr apart7/Dukes Major CriteriaEvidence of endocardial involvementpositive echocardiogram for endocarditisoscillating intracardiac mass on valve or supporting structure,or in the path of regurgitant jets,or on implanted material,in the absence of an alternate anatomic explanationabscessnew partial dehiscence of prosthetic valvenew valvular regurgitation(increase or change in pre-existing murmur not sufficient)7/Dukes Minor Criteriapredisposition(predisposing heart condition or iv drug use)fever of 100.40F or highervascular phenomena(major arterial emboli,septic pulmonary infarcts,mycotic aneurysm,intracranial hemorrhage,conjunctive hemorrhages,Janeway lesions)7/Dukes Minor Criteriaimmunologic phenomena(glomerulonephritis,Oslers nodes,Roth spots,rheumatoid factor)microbiologic evidence(positive blood culture not meeting major criteria or serologic evidence of active infection with organism consistent with IE)echocardiogram(consistent with IE but not meeting major criteria)7/Risk for EndocarditisHigh riskprosthetic cardiac valveprior episodes of endocarditiscomplex congenital cardiac defectsurgically constructed systemic-pulmonary shunts or conduits7/Risk for EndocarditisModerate riskpatent ductus arteriosusVSD,primum ASDcoarctation of the aortabicuspid aortic valvehypertrophic cardiomyopathyacquired valvular dysfunctionMVP with mitral regurgitation7/Risk for EndocarditisLow riskisolated secundum atrial septal defectASD,VSD,or PDA 6 months past repair“innocent”heart murmur by auscultation in the pediatric population“innocent”heart murmur by echocardiography in adult patients7/TreatmentPre-antibiotic era-a death sentenceAntibiotic eramicrobiologic cure in majority of patients7/New TreatmentsRight-sided infective endocarditis due to methicillin-susceptible S aureus(MSSA)in IV drug users2-wk therapy with a penicillinase-resistant penicillin and an aminoglycoside2-wk monotherapy with IV cloxacillinshort-term therapy is inappropriate if complicated by ostomyelitis,meningitis,myocardial abscess,or concomitant left-sided involvement7/New TreatmentsHighly penicillin-susceptible Streptococcus viridans or bovisOnce-daily ceftriaxone for 4 wks cure rate 98%easily administered as outpatient,avoid hospitalization,offers significant cost savingsOnce-daily ceftriaxone 2 g for 2wks followed by oral amoxicillin qid for 2 wksOnce-daily ceftriazone and netilmicin for 2 wks7/New TreatmentsProsthetic valve endocarditis due to fluconazole-susceptible Candida speciesmany are due to bloodstream invasionchronic oral suppressive therapy with fluconazole for inoperable disease7/SBE ProphylaxisStandard general prophylaxisamoxicillinUnable to take oral medsampicillinAllergic to penicilinclindamycincephalexinazithromycinclarithromycinAllergic to penicillin and unableclindamycinto take oral medicationscefazolin7/ReferencesPrevention of bacterial endocarditis.Recommended by the American Heart Association.Dajani AS,Taubert KA,Wilson W,et al.Circulation 1997;96:358-366New Criteria for diagnosis of infective endocarditis:Utilization of specific echocardiographic findings.Durack DT,Lukes AS,Bright DK,et al.Am J Med 1994;96:200-209Antibiotic treatment of adults with infective endocarditis due to strptococci,enterococci,staphlococci,and HACEK microorganisms.Wilson WR,Karchmer AW,Dajani AS.JAMA 1995;274:1706-17137/