Infective Endocarditis Flashcards
Pathophysiology
Infection of the endocardium
Risk factors
Previous infective endocarditis Prosthetic heart valves Rheumatic valve disease Congenital heart defects IVDU Dentures Immunocompromised
Symptoms
Fatigue Malaise Fever Night sweats HF symptoms
Signs
Osler’s nodes Janeway lesions Splinter haemorrhages Clubbing Roth spots HF signs New murmur
Consequences
Can cause stroke from septic emboli
Fever and new murmur
IE till proven otherwise
Causative organisms
Staph aureus - most common
Staph epidermidis - indwelling lines or recent cardiac surgery
Viridans streptococci - dental abscess/ procedures
Streptococcus bovis - colorectal cancer
Duke’s criteria
Definite diagnosis:
- Microorganisms in a vegetation
- Pathologic lesions
Major criteria:
- positive blood cultures
- endocardial involvement
Minor criteria: FEVER
- fever - 38+ Celsius
- emboli- Osler’s nodes and Roth’s spots
- vascular phenomena - arterial emboli, septic infarcts, conjunctival haemorrhage, janeway lesions
- evidence of active infection - +ve blood culture
- risk factors
When to suspect IE
2 major
1 major + 3 minor
All 5 minor
IE management
- antibiotics
- repeat echo
Antibiotic blind therapy
Native valve: amoxicillin + gentamicin IV
Allergy: vancomycin
Prosthetic valve: vancomycin, rifampicin + low dose gentamicin
Indications for surgery
- severe valvular incompetence
- aortic abscess
- abx resistance
- cardiac failure
- recurrent emboli after abx
Investigations
Blood culture x3 - 12hrs apart
TOE - vegetation
Roth’s spots
boat-shaped retinal haemorrhages with pale centre
Diagnostic criteria
Duke Criteria
