Infective Endocarditis

Question 1

What are the culture positive causes of Infective Endocarditis?

Answer 1

• Staphylococcus aureus (most common cause)
• Coagulase-negative Staphylococci such as Staphylococcus epidermidis (indwelling lines and most common cause of endocarditis in patients following prosthetic valve surgery). After 2 months, Staph aureus is the most common cause
• Streptococcus viridans (Streptococcus mitis and Streptococcus sanguinis in poor dental hygiene or following a dental procedure)
• Streptococcus bovis (colorectal cancer)
• Non-infective: systemic lupus erythematosus (Libman-Sacks), malignancy: marantic endocarditis

Question 2

What are culture negative causes of Infective Endocarditis?

Answer 2

• Prior antibiotic therapy
• Coxiella burnetiid
• Bartonella
• Brucella
• HACEK (Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, Kingella)
• Native valve endocarditis (NVE): amoxicillin + gentamicin
• NVE with severe sepsis, penicillin allergy or suspected methicillin-resistent staphylococcus aureus (MRSA) (vancomycin + gentamicin)
• NVE with severe sepsis and risk factors gram negative infection (Vancomycin + meropenem)
• Prosthetic valve endocarditis (vancomycin, gentamicin + rifampicin)

Question 3

What is the strongest risk factor for infective endocarditis?

Answer 3

Strongest risk factor for developing infective endocarditis is a previous episode of endocarditis.

Question 4

Which patients are affected in infective endocarditis?

Answer 4

• Previously normal valves (50%, typically acute presentation)
• Rheumatic valve disease (30%)
• Prosthetic valves
• Congenital heart defects
• Intravenous drug users (IVDUs, e.g. typically causing tricuspid lesion)

Question 5

What are the examination findings on the hand for Infective Endocarditis?

Answer 5

Hands

• Clubbing
• Splinter haemorrhages
• Osler’s nodes - in the pulp of the finger caused by inflammation around the site of the infected emboli lodged in distal arterioles.
• Janeway lesions - Flat, Non-tender red spots found on the palms and soles that blanche with pressure

Question 6

What are the investigations taken for infective endocarditis?

Answer 6

• Take a full blood count to show normocytic, normochromic anaemia with raised white cell count
• Test for Erythrocyte Sedimentation rate
• Take blood cultures
• Echocardiography may show vegetations

Question 7

What is the management of Infective Endocarditis?

Answer 7

• Intravenous benzylpeniccilin and Gentamicin.
• If seriously unwell, cloxacillin is added
• Surgery for prosthetic valves

Question 8

What are the examination findings on the face and neck for Infective Endocarditis?

Answer 8

• Petechiae which are found in conjunctiva, palate and skin
• Anaemia
• Examine the fundus for Roth Spots

Question 9

What are the examination findings on the Auscultation for Infective Endocarditis?

Answer 9

Listen to the heart for murmurs

• Common in Tricuspid and Aortic valves (aortic regurgitation),
• Look for signs of cardiac failure

Question 10

How is the abdomen examined in infective endocarditis?

Answer 10

• Examine the abdomen for Splenomegaly
• Test urine for Haematuria