Infective Endocarditis Flashcards
What is infective endocarditis. (2)
Infection of the endothelium.
Usually involves the valves.
What are the vegetations found in infective endocarditis composed of. (3)
They are a mixtures of bacteria, fibrin and platelets.
What are the causes of infective endocarditis. (3)
Bacteria.
Fungi.
Other.
What is the most common bacteria involved in IE in IVDU.
Streptococcus viridans.
What percentage of IE have no identified causative organism.
Approximately 10%.
What bacteria are involved in IE. (5)
Staphylococcus aureus/epidermidis. Streptococci viridans. Enterococci. Chlamydia. Gram negative bacteria (rarely: haemophilus, actnobacillus, cardiobacterium, eikenella, kingella).
What two categories is IE divided into.
Acute endocarditis.
Subacute endocarditis.
What is the difference between acute endocarditis and subacute endocarditis. (2)
Acute endocarditis is a rapidly progressive illness.
Subacute endocarditis is a slowly progressive condition.
What are the symptoms of IE. (4)
Fever.
Anorexia.
Weight loss.
Myalgia.
What is Duke’s criteria for IE.
It is a way of diagnosis IE.
What aspects of Duke’s criteria are needed to positively diagnose IE. (3)
2 major criteria.
1 major criteria and 3 minor criteria.
5 minor criteria.
What are the major criteria of Duke’s criteria for IE. (2)
Blood culture positive for typical organism or persistently positive.
Evidence of endocardial involvement.
What are the minor criteria of Duke’s criteria for IE. (5)
Fever.
Previous heart condition or IVDU.
Immunological phenomena: osler’s nodes, roth spots, glomerulonephritis, clubbing, petechia, arthralgia.
Vascular phenomena: mocotic aneurysms, Janeway lesions, septic emboli, intracranial haemorrhage, visceral infarct, splinter haemorrhages.
Positive blood culture with atypical bacteria.
What are osler’s nodes.
Raised tender nodules on finger pulps.
What are roth spots.
Small boat shaped retinal haemorrhages with a pale centre.
What are Janeway lesions.
Painless macules on the palm or sole of feet.
What is fever+new murmur until proven otherwise.
Infective endocarditis.
When should you take blood cultures in a patient presenting with a fever.
Any fever lasting >1week in those known to be at risk of developing IE.
Where do 50% of all endocarditis occur.
In normal valves.
How does infective endocarditis typically present. (3)
It follows an acute course.
Presents with acute heart failure and emboli.
What are the risk factors for developing acute IE. (6)
Dermatitis. IV injections. Renal failure. Organ transplantation. DM. Post-op wounds.
What is the usual via of entry for acute IE.
Via the skin.
What is the mortality rate for acute presentations of endocarditis.
5-50%.
What is the mortality rate for acute endocarditis related to. (2)
Age and embolic events.
Where does subacute endocarditis tend to occur.
On abnormal valves.
What are the risk factors for developing subacute endocarditis. (6)
Aortic or mitral valve disease. Tricuspid valves in IVDU. Coarctation. Patent ductus arteriosus. VSD. Prosthetic valves.
What are the two aetiologies of IE on prosthetic valves. (2)
Early (during surgery).
Late (haematogenous).
What are some fungal causes of IE. (3)
Candida.
Aspergillus.
Histoplasma.
What are the other causes of IE. (2)
SLE.
Malignancy.
What are the clinical signs of IE due to. (4)
Septic signs.
Cardiac lesions.
Immune complex deposition.
Embolic phenomena.
What are the septic signs of IE. (8)
Fever. Rigors. Night sweats. Malaise. Weight loss. Anaemia. Splenomegaly. Clubbing.
What are the cardiac lesion signs of IE. (2)
Any new murmur.
Any change in a pre-existing murmur.
What is a common cause of death in IE.
Left ventricular failure.
What are the immune complex deposition signs of IE. (7)
Vasculitis. Acute renal failure. Roth spots. Slinter haemorrhages. Osler's nodes. Glomerulonephritis. Microscopic haematuria.
What are the embolic signs of IE.
Emboli may cause abscesses in the relevant organ (brain, heart, kidney, spleen, gut, lung, skin - Janeway lesions).
What is the mortality rate of IE. (3)
30% with staphs.
14% if bowel organisms.
6% if sensitive streptococci.
What are the ECG changes associated with IE.
long PR interval at regular intervals.
What may be seen on the blood tests of a patient with IE. (3)
Normocytic normochromic anaemia.
High ESR/CRP.
Neutrophilia.
