Fever and a new murmur

Question 1

Features clinically of endocarditis

Answer 1

Symptoms of infection: fever, lethargy, gradual?
Embolic phenomena: Splinter haemorrhages, sometimes conjunctival
Valve abnormal: Early diastolic murmur (aortic regurgitation)

Question 2

Mitral stenosis

Aortic stenosis

Aortic regurg

Answer 2

Mitral stenosis: A soft, long diastolic murmur

Aortic stenosis: High pitched cresendo-decresecendo systolic murmur

Aortic regurg; A soft, early diastolic murmur

Question 3

Endocarditis pathogenesis

note can not be cured by host defences due to no neutrophil invasion. (viridans streptococci, staph aureus, enterococcus faecalis)

Answer 3

• Generally occurs to people with congenitally abnormal heart valves. Turbulent flow
• Platelets and fibrin attach to damaged valvular epithelium forming sterile vegetations
• Transient bacteraemia arising form mouth, skin etc onto these sterile vegetations
• Infected vegetation enlarges and sheds infected emboli, valvular destruction
• Heart failure through impaired valvular function or emboli causing infarct

Question 4

Continuous bacteraemia and endocarditis

Answer 4

With typical infections, times of transient bacteraemia
Bacteria always shed, so all blood cultures positive with an organism.
Culture blood on 3 occasions at least 20 mins apart, 90/100% +ve (so next few hours, or days) with an organism that can cause endocarditis

Question 5

Treatment for endocarditis

Answer 5

Bactericidal antibiotic for weeks
Dependent on organisms
IV, high dose, 2-4 weeks. 
70-90% cure rate
Strep viridans: penicillin + gentamicin 
Staph: flucloxacillin
Enterococcus: amoxycillin + gentamicin

Question 6

Endocarditis microbial aetiology

Answer 6

MOSTLY viridans streptococci, which are alpha haemolytic. Resident in mouth, gut etc
Then staph aureus, then enterococcus faecalis, HACEK

Question 7

Rheumatic fever versus endocarditits

Answer 7

Strep pyogenes pharyngitis ONLY, immune response to GAS leading to inflammation of joints, valves, heart, skin, brain. INFLAMMATION, not infection. Immunologic damage to valves. Oral penicillin 10 days, prophylaxis IM penicillin for many years. May however be a damaged heart valve eg in childhood

Endocarditis: Viridans step + others, mouth commensals, valve INFECTION, vegetation, treat IV penicillin for one month, prophylaxis with oral penicillin when dental work