Lecture 22: Fever and a new Murmur

Question 1

Endocarditis pathogenesis?

Answer 1

1. Turbulent flow through the abnormal valves (normally arotic or mitral), due to congenital abormality, nodules from rheumatic heart disease etc.
2. Platelts and fibrin attach to damaged valvular epithelium forming sterile vegetations
3. Transient bacteria arising from mouth, skin, gut, urinary tract, ect, seeds bacteria onto sterile vegetations
4. Infected vegetation enlarges and sheds infected emboli and leads to vascular destruction

Question 2

Organisms that cause endocarditis?

Answer 2

These will get into the blood of normal people quite often but will be destroyed by neutrophils within minutes. It is when there is already an abnormal valve of somekind that they can attach onto.

Question 3

Diagnostic methods for endocarditis?

Answer 3

CONSTANT BACTERAEMIA

• High conc of bacterian in and on the vegetation, with bacteria continually shed from vegetation into blood.
• Culture the blood on 3 occassions at least 20min apart
• Be aware of contaminant or transient bacteraemia

LISTEN FOR MURMUR

PERFORM ECHOCARDIOGRAM

LOOK FOR EVIDENCE OF EMDOLI (transient ischaemia, vision loss, loss of muscle control)

Question 4

Things to think about when deciding on an antimicrobial treatment?

Answer 4

Antimicrobial agent: (against just the single organism)

• sensitive or resistant
• exquisitely sensitive or just sensitive
• bactericidal (kill) or bacteristatic (just stops growth - not useful here)

Dose and method of administration

Duration of treatment for cure and prevention of relapse

Question 5

Differences between RF and Endocarditis

Answer 5