Infective Endocarditis

Question 1

Ms AC, a 32 y.o. woman who is known to misuse alcohol and IV drugs present to A+E complaining of gradual onset of malaise, fever, wt loss and night sweats.

she is pyrexial (38.5˚C). she has a pansystolic murmur which is thought to be a new finding and you suspect she has infective endocarditis.

Answer 1

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Question 2

a) other than IV drug abuse, name 4 other risk factors than could result in this condition.

Answer 2

1) pathogen introduction
- dental surgery
- thoracotomy
- catheterisation
- peripheral/central lines
- immunosuppression

2) abnormal cardiac endothelium
- prosthetic heart valve
- pre-existing valvular disease i.e. rheumatic, congenital, acquired

Question 3

b) list 4 additional clinical signs that may be found on examination to confirm this dx.

Answer 3

• murmur
• anaemia
• abscess
• clubbing
• Roth spots
• Osler’s nodes
• splinter haemorrhages
• splenomegaly
• Janeway’s lesions
• haematuria
• petechiae

Question 4

c) name the 2 most likely organisms to be implicated in infective endocarditis.

Answer 4

• streptococcus viridans

- staphylococcus aureus

Question 5

d) name 2 ix that are mandatory to confirm your dx.

Answer 5

1) blood cultures - 3 sets taken at different times and from different places
2) trans-thoracic ECHO - detect vegetation

• TOE better than TTE but TTE done first
• others: FBC, U+E, CRP

Question 6

e) your FY2 asks you to test the urine. what would you expect to find and what is the pathology that leads to this abnormality in the urine?

Answer 6

microscopic haematuria due to GN (immune complex deposition) or renal infarct (septic emboli)

Question 7

f) on further examination, you can also hear another PSM. this is the loudest at the left sternal edge and and you demonstrate their JVP is elevated with giant ‘v’ waves. in addition, Ms AC also has tender pulsatile hepatomegaly. what is the most likely cardiac lesion to be responsible for this, given the hx and ex?

Answer 7

tricuspid regurgitation