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CC Sept 2015 Infective Endocarditis

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echoecho's version from 2015-10-29 02:29

Section

Question Answer
Define infective endocarditis (IE)?infection of the endocardium
IE often typically involves what part of the endocardium? it is caused by what?1) valves and adjacent structures 2) caused by bacteria and fungi
Prior to widespread of what therapy, endocarditis was almost universally fatal?antimicrobial
Even with adequate medical and surgical therapy, the mortality rate approaches ___%? Why?1) 20% 2) due to the difficulty in making the diagnosis
The incidence of IE is estimated to be 2-6 per 100,000 patients, although it thought to be higher among patients with what?IVDA (intravenous drug abuse)
Aoubt what % of patients undergoing valvular surgery develop IE?1-3%
List the risk factor categories for IE?1) patient factor 2) cardiac factor 3) comorbid conditions
List the specific risk factors for the patient factor category for IE?1) male sex 2) age > 60 y.o. 3) IVDA (intravenous drug abuse) 4) poor dentition
List the specific risk factors for the cardiac factor category for IE?1) previous endocarditis 2) structural heart disease like valvular disease and congenital heart disease 3) prosthetic heart valve - mechanical and bioprosthetic
List the specific risk factors for the comorbid conditions category for IE?1) presence of an intravascular device 2) chronic hemodialysis 3) HIV
In the past, what was the major cause of endocarditis? But with widespread treatment of strep pharyngitis, what are now the most common causes of IE?1) in the past the major cause was rheumatic valvular disease 2) currently causes are congenital changes like bicuspid aortic valve, aortic sclerosis and mitral valve prolapse
Which of the following are more likely to become infected versus the other (prosthetic vs native valves)? Prosthetic valves are more likely to become infected than native valves
List factors that do NOT increase risk for IE?1) autoimmune disease 2) alcoholism 3) cancer diagnosis 4) ischemic heart disease 5) cardiomyopathy 6) nonvalvular cardiac surgery
What are believed to be the typical source of infection?microemboli of bacteria or fungi in the bloodstream
What two things do these bacteria produce that allows for the organisms to attach to damaged endocardial surfaces?1) express an adhesive-producing virulence factor (Streptococcus mutans) OR 2) biofilm (coagulase-negative Staphylococcus)
What is the subsequent occurrence after the organisms attach to damaged endocardial surfaces?inflammation occurs that promotes formation of a thrombus (vegetation) that provides a relatively sheltered area for the infecting organisms to grow and shower the host with more microemboli
List the bacteria that do not produce adhesive factors, thus making them much less likely to cause IE?1) beta-hemolytic streptococci 2) enteric gram-negative bacteria
Starting from the most common bacterial cause of IE to the least common, list these bacterial causes?1) most common is Staphylococcus aureus 2) next common is Streptococcus viridans 3) next common is coagulase-negative Staphylococcus and Enterococcus.
Up to _____ of patients with IE may have negative blood cultures? Why?1/3; due to prior treatment with antibiotics
List the most common organisms that cause IE but have negative blood cultures?1) Coxiella burnetti 2) Bartonella 3) Legionella 4) Mycobacterium 5) Tropheryma whipplei 6) fungi
In 1908, Sir William Osler described the physical exam findings of classic IE. Name these?1) fever 2) positive blood cultures 3) presence of petechiae and embolic features 4) new murmur
List Sir Williams Osler peripheral findings?1) petechiae of the subconjunctiva and soft palate 2) linear hemorrhages w/in the nail beds (splinter hemorrhages) 3) painful subcutaneous nodules of palms and soles (Osler's nodes) 4) nonpainful macular lesions of the palms and soles (Janeway lesions)
What criteria currently is used as basis for current diagnosis of IE? Why?1) Duke Criteria 2) due to variability of presentation and seriousness of a missed diagnosis
*** Clinically DEFINITE dx of IE requires the presence of ____ major criteria OR ___ major plus ____ minor criteria OR ____ minor criteria?2; 1; 3; 5
*** Clinically POSSIBLE dx of IE requires ____ major and ____ minor criteria OR ____minor criteria?1; 1; 3
Define clinically rejected endocarditis?defined as a 1) firm alternative dx explaining the evidence of endocarditis 2) resolution of symptoms with 4 days or less of anttimicrobial therapy 3) no evidence of IE at surgery or autopsy 4)no criteria for endocarditis met
Using the Duke Criteria for the dx of IE, list the 2 MAJOR criteria? 1) blood culture positive for typical micrroorganisms that cause IE such as Streptococci viridans, Streptococci bovis, Staphylococcus aureus, Enterococcus, or HACEK bacteria [Haemophilus species, Aggregatibacter aphrophilus, Haemophilus paraphrophilus, Aggregatibacter actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, Kingella kingae]), from 2 separate blood cultures drawn at least 12 hours apart, or all of 3 blood cultures positive (with the first and last drawn at least 1 hour apart), or a majority of 4 blood cultures positive (with the first and last drawn at least 1 hour apart). 2) evidence of endocardial involvement on echocardiogram
Using the Duke Criteria for the dx of IE, list the 5 MINOR criteria?1) predisposition for IE (either valvular disease or IVDA) 2) temperature > 38 C 3) vascular phenomenon (major arterial emboli, septic pulmonary infarcts, mycotic aneurysm, intracranial hemorrhage, conjunctival hemorrhage, Janeway lesion) 4) immunologic phenomena (glomerulonephritis, Osler's nodes, Roth's spots, rheumatoid factor) 5) positive blood culture that does not meet a major criteria above
*** How many sets of blood cultures should be drawn prior to the initiation of antimicrobial therapy, ideally at least ___ hours apart?2; 12
List the patients that should have transesophageal echo (TEE) vs. transthoracic echo (TTE)?1) prosthetic valve patients 2) patients with "possible endocarditis" or higher based on clinical criteria 3) patients who are difficult candidates for imaging due to body habitus 4) patients w/ suspected complicated endocarditis
List the findings on echocardiogram that would be positive for IE?1) oscillating intracardiac mass on a valve or supporting structures in the path of regurgitant jets or on any implantable material 2) an abscess 3) a new partial dehiscence of a prosthetic valve 4) new valvular regurgitation
When is a repeat TEE after an initial negative TTE recommended?1) patients w/ high risk features on the TTE OR 2) increased suspicion of IE during the clinical course
List the 2 groups of antimicrobial therapy for IE?1) empiric therapy (before the final blood culture results are available) 2) specific therapy (once the organism is identified)
Recommended empiric therapy is chosen according to the underlying characteristics of the patient, list these?1) IVDA or native valve involved = use an anti-staphylococcal penicillin and gentamicin (substitute vancomycin if the patient is penicillin allergic) 2) prosthetic valve = use vancomycin and gentamicin and rifampin
List the definitive antimicrobal therapy and duration of therapy if the organism is a PENICILLIN- susceptible viridans strep or Strep bovis?may use either of the following = 1) PCN G / ceftriaxone x 4 weeks OR 2) PCN G plus gentamicin x 2 weeks OR 3) Ceftriaxone plus gentamicin x 2 weeks OR 4) Vancomycin x 4 weeks
List the definitive antimicrobal therapy and duration of therapy if the organism is a relatively PENICILLIN-resistant viridans strep or Strep bovis?may use either of the following = 1) PCN G / ceftriaxone plus gentamicin x 4 weeks (penicillin/ceftriaxone) 2 weeks (gentamicin) OR 2) Vancomycin x 4 weeks
List the definitive antimicrobial therapy and duration of therapy if the organism is a Penicillin-resistant viridans Strep or Strep bovis?may use either of the following = 1) Ampicillin plus gentamicin (4-6 weeks) OR 2) Penicillin G plus gentamicin (4-6 weeks) OR 3) Vancomycin (6 weeks)
List the definitive antimicrobial therapy and duration of therapy if the organism is a Oxacillin-susceptible staph? may use either of the following = 1) Nafcillin/oxacillin plus gentamicin (6 weeks (nafcillin/oxacillin) and 3-5 days (gentamicin) OR 2) Cefazolin plus gentamicin (6 weeks cefazolin and 3-5 days gentamicin)
List the definitive antimicrobial therapy and duration of therapy if the organism is Oxacillin-resistant staph?1) Vancomycin (6 weeks)
List the definitive antimicrobial therapy and duration of therapy if the organism is an Enterococcus sp. susceptible to PCN, gentamicin and vancomycin?may use any of the following= 1) Ampicillin plus gentamicin (4-6 weeks) OR 2) Penicillin plus gentamicin (4-6 weeks) OR 3) Vancomycin plus gentamicin (6 weeks)
List the definitive antimicrobial therapy and duration of therapy if the organism is Enterococcus sp. susceptible to penicillin, streptomycin, and vancomycin but resistant to gentamicin?may use any of the following= 1) Ampicillin/penicillin plus streptomycin (4-6 weeks) OR 2) Vancomycin plus streptomycin (6 weeks)
List the definitive antimicrobial therapy and duration of therapy if the organism is Enterococcus sp. susceptible to gentamycin and vancomycin but resistant to penicillin?may use any of the following= 1) Ampicillin-sulbactam plus gentamicin (6 weeks) OR 2) Vancomycin plu gentamicin (6 weeks)
List the definitive antimicrobial therapy and duration of therapy if the organism is HACEK organism ?may use any of the following = 1) Ampicillin plus gentamicin (4 weeks) OR 2) Ceftriaxone (4 weeks)
Valve replacement is recommended for what type of patient?1) pts w/ recurrent emboli 2) staphylococcus infection of a prosthetic valve 3) infection with gram-negative yeast (non-albicans Candida) 4) failure of medical therapy 5) refractory heart failure
In 2011, study of > 4,000 patients with IE and known heart failure showed that there was lower in-hospital and 1 year mortality if what was done? valvular surgery (suggesting that any pt w/ heart fialure may benefit from early surgical intervention
Larger vegetations (> 1 cm) are at higher risk for what?embolization and mortality
Is large vegetations an indication for valvular replacement?some experts think so
*** Pts admitted with IE whose _____ level is elevated have increased mortality and greater need for valve replacement than those with normal levels?troponin I
***Pts w/ high levels of _____ after 1 week of adequate medical therapy are also at high risk for poor outcomes defined as severe infectious complications or death?CRP (C-reactive protein)
IE with which organism is associated w/ poorer outcomes and mortality when compared to infection w/ other organisms?staphylococcus
***The chronic use of antiplatelet agents, primarily _____ (dose?), was associated with a trend to lower morality in pts diagnosed w/ IE although the rate of embolism was unchanged?ASA 80-325 mg/day
The use of ASA was felt to do what? Do beta-blockers, ACEI, or other antiarrhythmic agents or warfarin do what ASA dose?1) reduce the size and bacterial density in valvular vegetations. 2) no
Heart failure in patients with IE is associated with increased mortality due to what?valvular disease
The American Heart ASsociation (AHA) published guidelines on prevention of IE in 2007. Prophylaxis is recommended for eligible patients undergoing what procedures?1) dental procedure involving manipulation of gingival tissue 2) periapical region of the teeth 3) perforation of oral mucosa 4) invasive respiratory tract procedures (tonsillectomy) 5) surgical procedures on infected skin
Prophylaxis is not recommended for what 2 procedures?GU or GI procedures
*** List the names of the prophylactic antibiotics for IE?1) amoxicillin 2 grams 1 hour prior to procedures for nonallergic patients 1) Cephalexin, Clindamycin, or Azithromycin for pts who are allergic to PCN)
*** List the patient types that prophylactic antibiotics are only recommended for?1) prostehtic cardiac valve or prosthetic material used for cardiac valve repair 2) previous IE 3) congenital heart disease such as (a) unrepaired cyanotic congenital heart diseae, including palliative shunts and conduits (b) completely repaired congeital heart defect with prosthetic material or device within the first 6 months after the procedure (c) repaired congenital heart defect with residual defects at the site or adjacent to the site of a prosthetic patch or device 4) cardiac transplantation patients who develop valvulopathy
The AHA published guidelines for dx and mgmt of IE in 2005. Is this still endorced by the AHA? What is the website with these guidelines1) yes 2) http://circ.ahajournals.org/cgi/content/full/111/23/e394
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