Infective Endocarditis Flashcards
Baumgarn
What is infective endocarditis (IE)?
Conditions that involve the inflammation of the endocardium and the valves that separate the heart chamber
Caused by bacteria and can have a variety of different sx and complications
Early identification & tx are crucial to prevent a wide range of complications, both w/in and outside the heart
What bacteria/pathogens are associated w IE?
Streptococci, staphylococcus, enterococci
Virdans group strep
E faecalis
Staph aureus
Strep gallolyticus: colon cancer indicator
HACEK pathogens: fastidious oropharyngeal gram negative bacteria (slow growers)
Haemophilus spp.
Aggregatibacter spp
Cardiobacterium hominis
Eikenella corrodens
Kingella kingae
What are some risk factors for IE?
Prosthetic heart valve*
Previous infective endocarditis *
Healthcare-related exposure (dental surgery)*
Congenital heart disease
Invasive medical device: chronic IV access/cardiac implantable device
Diabetes mellitus
Acquired valvular dysfunction (rheumatic heart disease)
HF
Mitral valve prolapse/regurgitation
IV drug abuse /persons who inject drugs (PWID)*
What is the pathophysiology of IE?
Bacterial Vegetation
High-inoculum bacterial aggregate on heart valves
Vary in size: millimeters to centimeters
May form a biofilm*
Mitral and aortic valves (most often affected)*
Tricuspid valve (right side endocarditis)*
- IV drug abuse
What are the clinical presentations of IE?
Sx: fever, heart murmur, peripheral manifestations
Subacute: weakness/malaise, dyspnea, night sweats, chills, chest pain, fatigue
Acute: sepsis
What are some peripheral manifestations of IE?
Osler’s Nodes: painful subcutaneous erythematous papules/nodules on pads of fingers and toes
Janeway’s Lesions: painless hemorrhagic plaques on palms of hands or soles of feet
Splinter Hemorrhages: linear hemorrhages under nail beds of fingers or toes
Roth Spots: retinal infarct w central pallor and surrounding hemorrhage
What are some diagnostic tests of ?
Blood cultures: three separate sets
- Continuous bacteremia: bacteria shedding from vegetation
- Positive blood cultures: 90-85% of most cases
- Culture-negative: no growth after 48-72 hours
- Retain blood bultures to detect growth of fastidious organisms
Chest X Ray
Pulmonary septic emboli
Echocardiogram (ECG)
Performed for all patients w suspected infective endocarditis
What are the two methods of ECG?
Transthoracic echocardiography (TTE)
Transesophageal echocardiography (TEE)
Detects valvular vegetations
TTE: 58-75% sensitivity
TEE: 85-90% sensitivity, 90% specificity
Which method of ECG (TTE vs TEE) is used when more definitive dx is needed?
TEE
TTE first before TEE bc it’s less invasive, unless you need a more definitive dx bc more specific
How is IE dx? the criteria
Definite Dx: 2 major criteria, 1 major and 3 minor criteria, or 5 minor criteria
Possible Dx: 1 major and 1 minor criteria or 3 minor criteria
What is considered a major criteria for dx of IE?
Blood culture positive for IE
Evidence of endocardial involvement
What is considered a minor criteria for dx of IE?
Predisposing factors
Ex: IV Drug use
Fever ( > 100.4 F)
Vascular phenomena
Immunologic phenomena
Microbiological evidence
What is the general tx for IE?
Nonpharmacological interventions:
Surgery: valvectomy/valve replacement
Required in 50% cases
Indications: HF, persistent bacteremia/vegetation, valve dysfunction, resistant organisms
Concerns: appropriate timing of surgery or duration of postoperative antimicrobial therapy
Antimicrobial therapy
Bactericidal antimicrobial agents: high dose parenteral therapy
Extended duration (4-6 weeks)
What is the empiric tx recommendations of IE?
IE caused by S. aureus with awaiting susceptibility results: Vancomycin plus cefazolin is appropriate for empirical coverage
Empirical therapy is generally required during the period between blood culture collections and the determination of pathogen
Acute clinical presentations of NVE, coverage for S. aureus, β-hemolytic streptococci, and aerobic Gram-negative bacilli: vancomycin and cefepime
Subacute presentation of NVE, empirical coverage of S. aureus, VGS, HACEK, and enterococci: vancomycin and ampicillin-sulbactam
Empirical antimicrobial therapy for suspected infection should be avoided unless the patient’s clinical condition (eg, sepsis) warrants it.
What lab value is more sensitive? CRP vs ESR
CRP
