Infective Endocarditis Flashcards
What is infective Endocarditis
Infection of heart valves and other endocardial lined structures within the heart
How do people catch infective endocarditis
- Regurgitant or prosthetic valves infected
2. Introduce infectious material into the blood stream or directly onto the heart during surgery
Clinical presentation of infective endocarditis
- Depends on site
- Signs of systemic infection (fever, sweats)
- Embolisation (stroke, bone infections, MI)
- Valve dysfunction (heart failure, arrhythmias)
What is the modified Dukes Criterion for diagnosis
2 Major:
- Bugs grown from blood cultures
- Evidence of endocarditis on echo or new valve leaks
5 Minor:
- Predisposing factors
- Fever
- Vascular Phenomena
- Immune Phenomena
- Equivocal blood cultures
Definite: 2 major, 1 major + 3 minor, 5 minors
Pros of Transthoracic echo
Safe, non invasive
no discomfort
Cons of TTE
Poor images so lower sensitivity
Transoesophageal Echo pros
Clearer pictures
Cons of Transoesophageal echo
Tube pushed down throat
Risk of perforation or aspiration
What is peripheral stigmata
Splinter haemorrhages
What are sober nodes
Tender nodules in the digits of a patient
What are laneway lesions
Haemorrhages and nodules in the fingers of patients with infective endocarditis
Characteristics of streptococci that cause infective endocarditis
Gram positive cocci in chains
How do we identify Strep. viridian’s
Optochin resistant
Types of colony made by strep. viridian’s
Alpha-haemolytic colonies
Characteristics of Staphylococci that cause infective endocarditis
Gram positive
Cocci
clusters
What test is performed on the Staphylococci being cultured overnight
- Coagulase test - shows a positive result for staph. aureus
How should staph. aureus respond to cefoxitin and penicillin
Resistance
How should staph. aureus respond to vancomycin
Sensitivity
What antibiotic is staph. aureus resistant to
cefoxitin - change to vancomycin
What test is performed to confirm staphylococcus is present
Coagulase test
Negative - staphylococcus
