Infective endocarditis Flashcards
Define Infective Endocarditis
Infection involving the endocardial surface of the heart (valves, chordae tendinae, endocardium)
Clinically = fever + new murmur
Aetiology of Infective Endocarditis
Most common = staph aureus
Native valve = Strep. Viridans
Prosthetic valves = coagulase -ve staph e.g. S. epidermis
IVDU = S. aureus (R-sided more likely)
Colorectal cancer = strep. bovis
Others: HACEK, fungi, SLE (libman-Sacks), malignancy
Culture negative: haemophilus, actinobacillus, cardiobacterium, kingella
Risk factors for Infective Endocarditis
History of IE
Prosthetic valves
Congenital heart disease
Post-heart transplant
Mitral valve prolapse
Hypertrophic cardiomyopathy
IVDU
Coarctation
Skin breaches, renal failure, immunosuppression, DM
Symptoms of Infective Endocarditis
Subacute:
Fever
Night sweats, malaise, fatigue, anorexia/weight loss, myalgia
Acute:
HF: SOB, orthopnoea, PND
Septic emboli: chest pain, arthralgia, stroke symptoms (weakness)
Anaemia
Signs of Infective Endocarditis
Pallor (anaemia)
Clubbing
Splinter haemorrhages
Janeway lesions
Oslers nodes
Roth’s spots off fundoscopy
New cardiac murmur
Vasculitis (haematuria, glomerulonephritis, AKI)
What is the criteria for Infective Endocarditis
Duke’s modified criteria
2 major OR 1 major 3 minor OR 5 minor
Major
2 +ve cultures of typical organisms
2 +ve cultures taken >12h apart / 2 or more where pathogen is less specific e.g. Staph A/epidermidis
positive serology for Coxiella burnetii, Bartonella species or Chlamydia psittaci
+echo with specific features
New valvular regurgitation
Minor
Predisposition (heart condition, IVDU)
Fever
Vascular phenomena
Immunological phenomena
MIcro +ve cultures not meeting major
Echo +ve but not meeting criteria
Investigations for Infective Endocarditis
BLOOD CULTURES (3x from different sites) - +ve for cause
FBC - leucocytosis (neutrophilic), normocytic anaemia
Raised ESR/CRP
LFTs - may show evidence of septic emboli
TTE (ECHO) - positive for IE, vegetations, oscillating structure, abscess formation, new valvular regurg
CXR - cardiomegaly, pulmonary oedema
Management for Infective Endocarditis
Empirical broad spectrum antibiotics 4-6 weeks
Native valve: amoxicillin ± gentamicin
Penicillin allergic/MRSA/sepsis: vancomycin + rifampicin + gentamicin
strep. viridans: benzylpenicillin
Prosthetics: Flucloxacillin + rifampicin + gentamicin
S. aureus: Flucloxacillin
When is surgery indicated by Infective Endocarditis
Haemodynamically instable
Abscess
Recurrent emboli
Prosthetic valves
Fungal endocarditis
Severe valvular incompetence
Antibiotic resistance
Complications of Infective Endocarditis
Congestive HF
Embolisation
Mitral valve vegetation
Valvular dehiscence, rupture, fistula
Splenic abscess
Prognosis for Infective Endocarditis
Mortality 5-50%
50% require surgery
20% in-hospital mortality
15% recurrence in 2 years
What procedures do not require Abx prophylaxis for infective endocarditis
dental procedures
upper and lower gastrointestinal tract procedures
genitourinary tract; this includes urological, gynaecological and obstetric procedures and childbirth
upper and lower respiratory tract; this includes ear, nose and throat procedures and bronchoscopy
