April 19,2007. Introduction Infective endocarditis ; uncommon but life- threatening condition High...
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Transcript of April 19,2007. Introduction Infective endocarditis ; uncommon but life- threatening condition High...
April 19,2007
IntroductionIntroduction
Infective endocarditis ; uncommon but life-threatening condition
High morbidity and mortality despite advance medical strategies
Many questions about IE prophylaxis efficacy from 1997 AHA guidelines
Classification of Classification of recommendationsrecommendations
Level of evidenceLevel of evidence
1997 document notable1997 document notable
Most case of IE attribute to daily activities bacteremias than invasive procedure
Acknowledgment of possible IE prophylaxis failures
Not well evidence-based(class2b, LOE C) Complicating
New IE prophylaxis guidelines from British Society for Antimicrobial Chemotherapy
Potential consequences of Potential consequences of changeschanges in recommendationsin recommendations
Violate long-standing expectations and practice pattern
Fewer patients eligible for IE prophylaxis Reduce malpractice claims related to IE
prophylaxis Stimulate prospective studies on IE
prophylaxis
Pathogenesis of IEPathogenesis of IE Formation of nonbacterial thrombotic endocarditis
(NBTE) ; turbulence flow Flow from high to low chamber Flow through narrow orifice
Bacteremia Mucosal injury
Bacterial adherence to NBTE FimA protein of viridans streptococci Staphylococcal adhesins of staphylococcus
Proliferation of bacteria within vegetation Rapidly multiply ; left > right More than 90% of mature organisms : inactive ; less response to
ATB
Host’s immune response contribute to clinical manifestations
Historical backgroundHistorical background Bacteremia causes endocarditis Viridans streptococci and enterococci are part of normal flora of oral
cavity and GI,GU tract respectively Susceptible to ATB ATB prophylaxis prevent endocarditis due to streptococci and
enterococci in animal models Large number, poorly documented case report of dental procedure
and IE Temporally relationship between dental procedure and onset of IE Evidence of viridans streptococci bacteremia after dental procedure Low risk of ATB adverse reaction High morbidity and mortality for IE patients
Lack of published data demonstrate prophylactic benefit
Rationale for or against Rationale for or against prophylaxis of IEprophylaxis of IE
Bacteremia-producing dental procedures Frequency, nature, magnitude and duration of bacteremia associated
with dental procedure Impact of dental disease, oral hygiene and type of dental procedure on
bacteremia Impact of ATB prophylaxid on bacteremia from dental procedure Exposure over time of bacteremia from daily activities compare with
dental procedures Results of clinical studies of IE prophylaxis for dental procedure Absolute risk of IE resulting from dental procedure Risk of adverse reactions and cost-effectiveness of prophylactic
therapy Cardiac conditions and endocarditis
Highest predisposition of IE Highest risk of adverse outcome from IE
Bacteremia-producing dental Bacteremia-producing dental proceduresprocedures
Frequency, nature, magnitude and duration of bacteremia associated with a dental procedure Wide variation of frequencies of bacteremia from dental procedure ; tooth
extraction, periodontal surgery, scaling and root planing, teeth cleaning, rubber dam matrix/wedge placement, endodontic procedure
Transient bacteremia occurs frequently in daily activities ; tooth brushing, flossing, wooden toothpicks, water irrigation devices, chewing food
Bacteremia from daily activities >>>> dental procedures Few published data exist on the magnitude of bacteremia from dental procedure
or daily activities life Relatively low bacteremia from dental procedure and daily activities, < 104
CFU/ml, less than experimental IE in animals, 106 to 109 CFU/ml Majority of IE patients had no dental procedure in 2 weeks before onset of
symptom No certain role of bacteremia duration and risk of IE No clinically significant different between dental procedure and daily activities
Bacteremia-producing dental Bacteremia-producing dental proceduresprocedures
Impact of dental disease, oral hygiene and type of dental procedure on bacteremia Controversial relationship between poor oral hygiene, extent of
dental and periodontal disease, type of dental procedure and the frequency, nature, magnitude, duration of bacteremia
Available evidences support : good oral hygiene and eradicating dental disease to decrease the frequency of bacteremia from routine daily activities
Numerous dental procedure associated with bacteremia similar to tooth extraction
Bleeding procedure? Lastest guidline : overemphasis ATB prophylaxis and
underemphasis good oral hygiene and routine dental care
Bacteremia-producing dental Bacteremia-producing dental proceduresprocedures
Impact of antibiotic therapy on bacteremia from a dental procedure Controversial of ability of ATB to prevent or reduce
frequency, magnitude, duration of bacteremia associated with dental procedure
Amoxicillin ; reduce but not eliminate bacteremia No data of amoxicillin for reduce or prevent IE Contradictory of efficacy of antiseptic
Bacteremia-producing dental Bacteremia-producing dental proceduresprocedures
Cumulative risk over time of bacteremias from routine daily activities compared with the bacteremia from a dental procedureCumulative exposure during 1 year to
bacteremia from routine daily activities may be as high as 5.6 million times greater than that resulting from a single tooth extraction
Result of clinical studies of IE Result of clinical studies of IE prophylaxis for dental proceduresprophylaxis for dental procedures
No prospective, randomized, placebo-controlled studies about efficacy of ATB prophylaxis to prevent IE in patients who undergo a dental procedure
Some retrospective studies : suggest a prophylactic benefit but a small in size and insufficient clinical data and prolonged onset of symptoms
Van der Meer ; dental procedure probably caused only a small fraction of cases of IE and prophylaxis ATB would prevent a small number of cases
Strom : dental treatment was not a risk factor for IE even in patients with valvular heart disease
Huge number of prophylaxis doses would be necessary to prevent a very low number of IE cases
Absolute risk of IE resulting from Absolute risk of IE resulting from a dental procedurea dental procedure
No published data accurately determine the absolute risk of EI that result from a dental procedure.
Time frame between bacteremia and the onset of symptoms of IE is usually 7-14 days
Many cases report and reviews included cases with a remote preceding events ; 3 to 6 months
Undetermined whether the bacteremia result from dental procedure or routine daily activities
Exceeding small amount of calculated cases of dental procedure-related IE
Risk of adverse reactions and cost-Risk of adverse reactions and cost-effectiveness of prophylactic therapyeffectiveness of prophylactic therapy
Nonfatal adverse reaction (rash, diarrhea, GI upset) commonly occur, not severe and self limited
In penicillin use and anaphylactic fatalities 36% in known allergy to penicillin 64% in no history of allergy
Fatal anaphylaxis in cephalosporin : less common
Fatal reaction to single dose of macrolide or clindamycin : extremely rare
Summary of bacteremia factorsSummary of bacteremia factors
Lacking of scientific proof for IE due to dental procedure and efficacy of prophylaxis ATB in cardiac risk factors patients
Extremely small number of IE caused by bacteremia-producing dental procedure
Extremely small number of IE cases might be prevented by ATB prophylaxis even 100% effective
Majority of IE : caused by oral microflora and random bacteremia caused by routine daily activites
Dental disease may increase risk of bacteremia associated with routines activities
Emphasis shift from previous dental procedure-related bacteremia and prophylacxis ATB to dental care and oral health
Cardiac conditions and Cardiac conditions and endocarditisendocarditis
Underlying conditions over a lifetime that have the highest predispositon to the acquisition of endocarditis Most common underlying condition for IE
Developing countries : RHD Developed countries : MVP
Steckelberg and Wilson report risk of IE per 100,000 patient-year
MVP without murmur 4.6 MVP with MR murmur 52 RHD 380 – 440 Mechanical or bioprosthetic valve 308 – 383 Valve replacement for native IE 630 Previous IE 740 Valve replacement for prosthetic IE 2160
Cardiac conditions and Cardiac conditions and endocarditisendocarditis
Underlying conditions over a lifetime that have the highest predispositon to the acquisition of endocarditisCHD
Minor to severe, complex cyanotic heart disease Increase various intracardiac valvular prosthesis,
graft, shunt and other devices Different level of risk for acquisition of IE
Cardiac conditions and Cardiac conditions and endocarditisendocarditis
Cardiac conditions associated with the highest risk of adverse outcome from endocarditis Viridans streptococcal IE mortality rate
Native valve : ≤ 5% Prosthetic valve : ≥ 20%
Enterococcal IE mortality rate : prosthetic valve > native valve Prosthetic IE take higher risk for : HF, cardiac valve replacement
surgery, perivalvular extension of infection and other complications Relapsing or recurrent IE : greater risk of CHF, cardiac valve
replacement surgery, higher mortality Multiple episodes of native or prosthetic valve IE : greater risk of
additional episodes of IE and more serious complications CHD : complex cyanotic heart disease and postoperative palliative
shunts, conduits or other prostheses have a high lifetime risk of acquiring IE and risk for morbidity and mortality
1997 risk classifications1997 risk classifications
Cardiac conditions and Cardiac conditions and endocarditisendocarditis
Should IE prophylaxis be recommended for patients with the highest risk of acquisition of IE or for patients with the highest risk of adverse outcome from IE? “In patients with underlying cardiac conditions
associated with the highest risk of adverse outcome from IE, IE prophylaxis for dental procedures may be reasonable, even though we acknowledge that its effectiveness is unknown (class 2b, LOE B)”
Regimens recommendedRegimens recommended
General principlesSingle dose before the procedureUp to 2 hours administration after procedure if
inadvertently not administrated before procedure
Beware IE in high risk patient who underwent the invasive procedure
Regimens for dental procedureRegimens for dental procedure
Class 2b, LOE C (unknown effectiveness)
Exists evidences of drug-resistance strains
Regimens for respiratory tract Regimens for respiratory tract proceduresprocedures
No published data conclusively demonstrate a link between RS procedure and IE
ATB prophylaxis was recommend in an invasive procedure involve incision of mucosa : tonsillectomy,
adenoidectomy Infection drainage : abscess, empyema
No role of ATB prophylaxis in bronchoscope without incision of mucosa
The same patient and regimen as dental procedure Beware staphylococcus
Recommendations for GI or GU Recommendations for GI or GU tract procedurestract procedures
Enterococci infection : GI and GU tract No published data link between IE and GI, GU tracts
procedures No studies exist demonstrate ATB prophylaxis prevent
IE in GI, GU procedures Increase frequency of enterococci resistant to penicillin,
vancomycin, aminoglycosides, but unknown significance about GI, GU tracts procedures IE prevention
Prophylaxis ATB solely to prevent IE is not recommend Diagnostic esophagogastroduodenoscopy colonoscopy
Recommendations for GI or GU Recommendations for GI or GU tract procedurestract procedures
Reasonable ATB prophylaxis in indicated patients with : Established GI or GU tract infection or Receive ATB to prevent wound infection or sepsis
associated with GI or GU tract procedure
ATB against entercocci : penicillin, ampicillin, piperacillin, vancomycin include in regimen
No published studies demonstrate efficacy
Class 2B, LOE B
Recommendations for GI or GU Recommendations for GI or GU tract procedurestract procedures
Reasonable ATB to eradicate enterococci in indicated patient with : Elective cystoscopy or Other urinary tract manipulation
Enterococcal urinary tract infection or colonization
Reasonable empiric or specific ATB against enterococci in non-elective procedure
Class 2B, LOE B
Recommendations for procedures Recommendations for procedures on infected skin, skin structure, on infected skin, skin structure,
musculoskeletal tissuemusculoskeletal tissue
Reasonable therapeutic regimen active against staphylococci and β-hemolytic streptococci in indicated patients with :Undergo surgical procedure that involves
infected skin, skin structure, musculoskeletal tissue
Class 2B, LOE C