Infectious Endocarditis Flashcards
Definition
infection of the heart valves by various microorganisms
Acute bacterial endocarditis
High fevers
Systemic toxicity
Leukocytosis
Death possible within days if left untreated
Subacute bacterial endocarditis
Slow, indolent course associated with low-grade fevers
Night sweats
Weight loss
Vague systemic complaints
Usually in setting of previous valvular damage
Risk factors for Endocarditis
Presence of prosthetic valve Previous endocarditis DM Health-care related exposure Congenital heart disease with cyanosis Acquired valvular dysfunction Hypertrophic cardiomyopathy Mitral valve prolapse with regurgitation Chronic IV access IV drug abuse
Common organisms in endocarditis
Staphylococcus
Streptococcus
Enterococci
HACEK organisms
slow growing, fastidious G- bacilli Haemophilus parainfluenzae/aphrophilus Actinobacillus actubinycetemcomitans Cardiobacterium hominis Eikenella coroodens Kingella kingae
Pathogenesis for endocarditis
Hematogenous spread via:
Endothelial surface damaged
Sterile platelet-fibrin thrombi form on surface
Bactermia gives organisms access to and results in colonization of the endocardial surface
After colonization of endothelial surface, a “vegetation” of fibrin, platelets, and bacteria forms
Complications secondary to vegetation formation
HF
Septic emboli
Antibody complexes can form and deposit in organs
Endocarditis sx
Fever Schills, night sweats Weight loss Weakness Malaise
Endocarditis signs
Fever
Heart murmur
Embolic phenomenon
Skin manifestations: osler nodes, splinter hemorrhages, Janeway lesions
Endocarditis lab findings
Positive blood cultures
Nonspecific: anemia, normal/slightly elevated WBC with a mild left shift, elevated ESR or CRP
Diagnostic tests for endocarditis
Transesophageal echocardiogram (TEE) is preferred Transthoracic echocardiogram (TTE) may also be performed
Osler’s nodes
Purplish or erythematous subcutaneous papules or nodules on the pads of the fingers and toesl These lesions are 2-15 mm in size and are painful and tender. These nodes are not specific for infective endocarditis.
Janeway’s lesions
Hemorrhagic, painless plaques on the palms of the hands or soles of the feet. Likely embolic in origin.
Splinter hemorrhages
Thin, linear hemorrhages found under the nail beds of the fingers or toes; not specific for infective endocarditis
Petechiae
Small, erythrematous, painless, hemorrhagic lesions
Clubbing of the fingers
Proliferative changes in the soft tissues about the terminal phalanges observed in long-standing endocarditis
Roth’s spots
Retinal infarct with central pallor and surrounding hemorrhage
Peripheral manifestations of endocarditis
Osler's nodes Janeway's lesions Splinter hemorrhages Petechiae Clubbing of the fingers Roth's spots
Major Duke criteria
Positive blood culture (at least 2 separate)
Evidence of endocardial involvement (via diagnostic test)
Minor Duke Criteria
Predisposition, predisposing heart condition or IVDU Fever (>100.4) Vascular phenomena Immunologic phenomena Microbiologic evidence
Vascular phenomena
Major arterial emboli, septic pulmonary infarcts, mycotic aneurysm, intracranial hemorrhage, conjunctival hemorrhages, Janeway’s lesions
Immunologic phenomena
Glomerulonephritis
Osler’s nodes
Roth’s spots
Rheumatic factor
Microbiologic evidence
Positive blood culture or serologic evidence of active infection with organism consitent with IE
Definitive IE
2 major criteria OR 1 major criteria + 3 minor criteria OR 5 minor criteria
Possible IE
1 major criteria + 1 minor criteria
OR
3 minor criteria
Veridans Group Streptococci, Native valve, IE therapy: PCN susceptible
Aqueous crystalline PCN G (12-18 mU/d) or ceftriaxone - 4 weeks OR same + gentamicin - 2 weeks OR Vancomycin - 4 weeks
Veridans Group Streptococci, Native valve, IE therapy: relative resistance to PCN
Aqueous crystalline PCN (24 mU/d) or ceftriaxone - 4 weeks + Gentamicin - 2 weeks
OR
Vancomycin - 4 weeks
Veridans Group Streptococci, Native valve, IE therapy: PCN resistant
Vancomycin + gentamicin - 6 weeks
Veridans Group Streptococci, Prosthetic valve, IE therapy: PCN-susceptible
Aqueous crystalline PCN (24 mU/d) or ceftriaxone - 6 weeks +/- gentamicin - 2 weeks
OR
Vancomycin - 6 weeks
Veridans Group Streptococci, Prosthetic valve, IE therapy: PCN relatively or fully resistant
Aqueous crystalline PCN G (24 mU/d) or ceftriaxone + gentamicin - 6 weeks
OR
Vancomycin - 6 weeks
Staphylococci Endocarditis, Native valve, IE therapy: MSSA
6 weeks
Nafcillin/oxacillin
OR
If PCN allergic: cefazolin
Staphylococci Endocarditis, Native valve, IE therapy: MRSA
6 weeks
Vancomycin/Daptomycin
Staphylococci Endocarditis, Prosthetic valve, IE therapy: MRSA
Vaconmycin > 6 weeks
Rifampin > 6 weeks
Gentamicin - 2 weeks
Staphylococci Endocarditis, Prosthetic valve, IE therapy: MSSA
Nafcillin/oxacillin > 6 weeks
Rifampin > 6 weeks
Gentamicin - 2 weeks
Enterococcal endocarditis, strains susceptible to PCN, gentamicin, and vancomycin
Ampicillin or aqueous crystalline PCN G + Gentamicin (4-6 weeks)
If CrCl < 50: ampicillin + ceftriaxone - 6 weeks
Vancomycin + gentamicin - 6 weeks
Enterococcal endocarditis strains susceptible to PCN, but resistant to aminoglycosides
Ampicillin + ceftriaxone - 6 weeks
Enterococcal endocarditis, strains susceptible to vancomycin and aminoglycosides, but resistant to PCN
Vancomycin + gentamicin - 6 weeks
Enterococcal endocarditis, strains resistant to PCN, vancomycin and aminoglycosides
Linezolid or daptomycin > 6 weeks
Therapy for HACEK endocarditis
Native valves - 4 weeks Prosthetic valves - 6 weeks Ceftriaxone Ampicillin/sulbactam If pt unable to tolerate a beta-lactam: Cipro
Surgery and endocarditis
- Important adjunt to antibiotic management in certain patients
- Valve removed and replaced: removes infected tissue and restores hemodynamic function
- Indications: HF, persistent fever, recurrent embolic events, prosthetic valves, abscesses, ineffective abx therapy, fungal IE
Procedures and prophylaxis recommendations
Dental - all procedures invlolving manipulation of gingival tissue or priapical region of teeth or perforation of the oral mucosa
Respiratory tract - no prophylaxis
GI or GU tract - no prophylaxis
Take 30-60 minutes before procedure
Prophylactic regimens: oral
Amoxicillin 2g
Prophylactic regimens: unable to take oral
Ampicillin 2g IM/IV
Cefazolin 1g IM/IV
Ceftriaxone 1g IM/IV
Prophylactic regimens: allergy to PCN - oral
Keflex 2g
Clinda 600mg
Azithromycin/Clarithromycin 500mg
Prophylactic regimens: allergy to PCN - unable to take oral
Cefazolin 1g IM/IV
Ceftriaxone 1g IM/IV
Clindamycin 600mg IM/IV
