6 - Endocarditis Flashcards
Where is endocarditis the most common?
- Mitral valve (need some damage to the valve that causes it to repair, giving a predisposition to endocarditis)
- Second most common is tricuspid (most common in IVDU)
Risk factors for endocarditis?
- Over 60 y/o
- Male
- Intravascular catheter, chronic hemodialysis, IVDU
- Oral hygiene/ dental pathology
- Immunocompromised
- Prosthetic valve
- Prior infective endocarditis
- Congenital or valvular heart disease
Signs and symptoms of endocarditis?
- Fever (can be low grade)
- New or worsening murmur
- Hematuria (RBCs in the urine)
- Vascular embolic events, splenomegaly, skin/ mucosal lesions
- Malaise, anorexia, weight loss
- Lab signs = leukocytosis, anemia, elevated ESR and CRP
What are the common pathogens for subacute, indolent endocarditis?
- Viridans strep
- HACEK (Haemophilus, aggregatibacter, cardiobacterium, eikenella, kingella)
- S. epidermidis
- Enterococcus
- Strep gallolyticus
What are the common pathogens of acute, invasive endocarditis?
- Group A, B, C, and G strep
- Staph aureus
What is the most likely pathogen of PVE w/in 2 months of surgery?
CoNS and staph aureus
What is the most likely pathogen of endocarditis w/ a negative blood culture?
Zoonotic (coxiella burnetiid, bartonella, brucella)
Complications of endocarditis?
- Embolization including stroke
- New or worsening heart failure
- Intracardiac abscess
- Arrhythmias
- Mortality rate 15-25% (40% at 5 years)
What causes the majority of complications of endocarditis?
- Poor prognosis in prosthetic valves
- Advanced age
- Co-morbidities
- Heart failure
- Embolic events
- Fungal, gram neg, and left-sided staph aureus endocarditis
What is required w/ gram neg and fungal endocarditis?
Valve replacement b/c these infections are very hard to treat w/ antibiotics
What are the “major” Duke’s criteria for diagnosis of endocarditis?
- Positive IE blood culture of staph aureus, viridans strep, S. gallolyticus, community-acquired enterococcus, or HACEK (2 draws > 12 h apart or 3 draws > 1 h apart)
- Positive zoonotic serology
- Echocardiogram for vegetation, pseudoaneurysm, or abscess
Which streptococci are associated w/ endocarditis?
- 75% viridans group strep (comes from the mouth); 15-20% pyogenic strep
- From viridans group (from most to least common) - S. mitis, S. sanguinis, S. gallolyticus, and S. mutans
What are the principles of endocarditis antibiotic therapy?
- High-dose IV therapy for plasma concentrations that penetrate the vegetation
- Bactericidal against high density bacteria w/ low metabolic, stationary growth phase
- Duration that sterilizes the vegetation
Antimicrobial options for NVE caused by Viridans group strep, S. gallolyticus (Pen-S, MIC < 0.1)
- 4 w penicillin 12-18 MU/d CI or dosed q4h
- 4 w ceftriaxone 2g q24h
- [4 w vanco 15 mg/kg q12h] for allergy
Antimicrobial options for uncomplicated NVE caused by Viridans group strep, S. gallolyticus (Pen-S, MIC < 0.1)? What is considered uncomplicated NVE?
- <5 mm, no CV risks or embolic events, good tx response
- 2 w penicillin 12-18 MU/d CI or q4h + gentamicin 3 mg/kg q24h
- 2 w ceftriaxone 2g q24h + gentamicin 3 mg/kg q24h
- [4 w vanco 15 mg/kg q12h] for allergy