Endocarditis Flashcards
(29 cards)
What is meant by bacteraemia?
Presence of bacteria in the bloodstream
What temperature are blood cultures kept at?
37’C
The presence of bacteraemia is diagnostic of endocarditis. True/False?
False
Just indicates that there is infection somewhere in the body, or that samples may be contaminated
What is the commonest coagulase -ve Staph organism?
Staph epidermidis
What does Staph epidermidis commonly contaminate?
Skin
Prosthetic material
What is infective endocarditis?
Infection of the heart valves
What are the commonest factors that predispose to endocarditis?
Rheumatic disease Congenital abnormalities IV drug users Calcification/sclerosis Prosthesis/intravascular lines
What is the general pathogenesis of endocarditis?
Damaged heart valves produce turbulent flow over irritated endothelium, causing platelet/fibrin deposition upon which bacteria settle, producing vegetation over the valve
Which organism is the most common cause of native valve endocarditis?
Staph aureus
Which organism is the 2nd commonest cause of native valve endocarditis?
Strep viridans
Name some atypical organisms that cause endocarditis
Coxiella burnetti
Brucella
Gram -ve organisms
Fungi
What are some symptoms of acute endocarditis?
Breathlessness Fever Tiredness Malaise Weight loss
What are some signs of endocarditis?
New/louder murmur Clubbing Splinter haemorrhage Splenomegaly Roth spots, Janeway lesions, Osler nodes Night sweats
What are roth spots?
Retinal haemorrhages
What are Janeway lesions?
Nodular haemorrhagic lesions on palms and soles
What are Osler nodes?
Painful red lesions on palms and soles
How many blood cultures are taken for diagnosis of endocarditis? What criteria is used?
3 sets (2 positive) Dukes criteria
If 3 blood cultures are taken and only 1 comes back positive, what might have been the cause?
Contamination
Transthoracic echo is more effective than transoesophageal echo. True/False?
False
What organisms are usually responsible for prosthetic valve endocarditis?
Staph aureus
Staph epidermidis
Endocarditis in IV drug users predominately affects which side of the heart? What organism typically?
Right side (tricuspid valve) Staph aureus
How does Staph aureus endocarditis produce pneumonia?
Vegetation lodges in pulmonary circulation, causing inflammation, infection and abscess
Which antibiotics are given for native valve endocarditis?
Amoxicillin IV
Gentamicin IV
Which antibiotics are given for prosthetic valve endocarditis?
Vancomycin IV
Gentamicin IV
Rifampicin oral
