Infective Endocarditis study notes Flashcards
What are HACEK organisms
A group of gram negative fastidious bacilli that require prolonged culture in 10% CO2 Haemophilus species (not influenza) Actinobacillus Cardiobacterium hominis Eikenella corrodens Kingella
What are commonest organisms in patients with native valve infective endocarditis
Streptococcus (45%) Viridans (including milleri, oralis, mitis, mutans, salivarius) or bovis
Staphylococcus aureus or epidermidis (35%)
Enterococcus Faecalis (10%)
Diptheroid bacillis and micro-aerophilic streptococci
HACEK
Anaerobic gram negative bacilli
Listeria, Bacteroides, fusobacterium, Legionella, Propionibacterium acnes, brucella abortus
Coxiella Burnetii (Q fever)
Chlamydia psittaci or trachomatis
Fungal
Candida
Aspergillus
Histoplasma
What are commonest organisms in patients with prosthetic valve infective endocarditis < 2months
Staphylococcus aureus and epidermidis (45-50%)
Gram negative bacilli
Fungi
Streptococcus and Entercoccus (<10%)
What are commonest organsims of prosthetic IE > 2months
Streptococcus viridans (45%) Staphyloccus aureus and epidermidis (35%) Enterococcus faecalis (10%)
What are causes of non-infective endocarditis
Anti-phospholipid syndrome (Hughes syndrome)
Acute rheumatic fever (Lancefield group A Streptococcus)
Libman-sacks endocarditis (SLE and scleroderma)
Mucinous adenocarcinoma (pancrease, lung, GI tract)
Other malignant disease–lymphoma, bladder CA
What are Dukes Minor criteria
Predisposing factors (IV drug use, cardiac lesion)
Fever > 38 degree C
Embolic or vascular phenomena
Immunological phenomena
Serology consistent with IE
Blood cultures compatable but not typical of IE
What are major criteria for Dukes Classification
1) Three positive Blood cultures (12 hours apart)
showing typical organisms (Strep bovis or viridans, Staph aureus, entercocci, or HACEK
2) Evidence of endocardial infection
vegetation, abscess, prosthetic valve dehiscence , new regurgitation
What is significance of Dukes Criteria
Definite endocarditis (Specificity 99% and sensitivity 80%)
Clinical diagnosis
1) 2 major criteria
2) 1 major and 3 minor criteria
3) five minor criteria
4) pathological diganosis by histological evidence of active infective endocarditis (post op specimen).
Graft selection for aortic root replacement in complex active endocarditis
UPenn from 2000 to 2010 in 134 patients
32.1 +/- 29.4 months follow up and showed 5 year survival rates betweem mechanical, bioprosthetic, and homograft of similar results (58% each)
What is rate of prosthetic valve endocarditis
0.5 to 1% per year following valve surgery
What valve are most likely to be infected
Left sided valves (mitral is more common then aortic)
5% involving the tricuspid and very rare for pulmonary
What is brief pathophysiology of infective endocarditis
platelet-fibrin thrombus formation with subsequent bacterial colonisation resulting in vegetation formation and spread into the surronding tissues
What is Roth spot
Retinal boat-shaped hemoorage with a pale center
What are splinter hemorrhages
thin reddish-brown lines in the nail bed
What are Osler’s nodes
painful pulp infarcts on fingers, toes, palms or soles
What are Janeway lesions
painless flat palmar and plantar erythema
What are most common organisms in early PVIE
Staph aureus and Stah epi (50%)
Gram negative
Fungi
Strep and Enterococcus (< 10%)
What antibiotics should be used for the common organisms in IE
Penicillin and gentamicin can be started
if you suspect stap then you need to start vanco
If enterococcus start amoxycillin and gentamicin
What is suggested treatment for HACEK
Start ceftriaxone
usually beta-lactam resistant
What are causes of non-infective (marantic) IE
musconous adenocarciumoa (pancreas, lung, upper GI tract)
other malignant disease –lymphoma, bladder carcinomoa
Anti-phospodlipid syndrome (hughes syndrome)
Acute rheumatic fever (GAP strep)
Libman-sacks endocarditis (SLE)
What is significance of Dukes Criteria
Specificitiy 99%
Sensitivity 80%
What are empiric antiobiotic treatments for acute IE
Empiric antibiotic therapy is chosen based on the most likely infecting organisms.
Native valve endocarditis (NVE) has often been treated with penicillin G and gentamicin for synergistic coverage of streptococci.
List coverage for IV drug users
Have been treated with nafcillin and gentamicin to cover for methicillin-sensitive staphylococci.
emergence of methicillin-resistant S aureus (MRSA) and penicillin-resistant streptococci has led to a change in empiric treatment with liberal substitution of vancomycin in lieu of a penicillin antibiotic
What is treatment regimen for prosthetic IE
Prosthetic valve endocarditis (PVE) may be caused by MRSA or coagulase-negative staphylococci (CoNS)
thus, vancomycin and gentamicin may be used for treatment, despite the risk of renal insufficiency.
Rifampin is necessary in treating individuals with infection of prosthetic valves or other foreign bodies because it can penetrate the biofilm of most of the pathogens that infect these devices.
What is dose of pen g
Endocarditis: 12-20 million units/day IV divided q4-6hr x4-6 weeks
What are rates of recurrence post IE
“Recurrence rates are approximately 5% to 12%.”
What are clinical features of infective endocarditis
Clinical features of infection: fever, night sweats, rigors, weight loss, malaise,
Immune complex depositions are:
Roth spots–retinal boat shaped hemorrhage with a pale center
Splinter hemorrhages–thin reddish-brown lines in the nail bed
Oslers Nodes—painful pulp infarcts on the fingers, toes, palms and soles
Janeway lesions–painless flat palmar or plantar erythema
vassulitis (brain, skin, kidney) and arthalgia
clinical features of cardiac lesion
clinical features of emboli
