Endocarditis

Question 1

Definition/ Classification

Answer 1

Infection of the endocardium most commonly caused by Strepococci or Staphylococci

Acute

• Develops days-weeks
• Tends to happen to normal valves

Subacute

• Develops weeks-months
• Tends to happen to abnormal valves

Question 2

Aetiology of Endocarditis

Answer 2

Bacteriaemia caused by

• Dental work
• UTI/ Urinary catheterisation
• Resp/ GI infection

Most common bacteria

• Strep Viridians
• Enterococcus
• S. aureus/ epidermis

Fungi

• Candida
• Aspergillus

SLE

Question 3

Risk factors for Endocarditis

Answer 3

History of IE

Artificial prosthetic valves

Congenital heart disease

Post-heart transplant

IVDU

Implanted cardiac devices

Question 4

Signs and symptoms of Endocarditis

Answer 4

Symptoms

• Malaise
• Fever
• Rigors/ sweats

Signs
- NEW murmur
- Weight loss
- Spilinter haemorrhages
- Janeway nodes (painless)
- Osler's nodes (painful)
- Roth spots
-

Question 5

Diagnosis of endocarditis

- Duke criteria

Answer 5

Criteria to diagnose endocarditis is

• 2 major
• 1 major and 3 minors
• all 5 minors

Major

• Positive blood culture (typical organism, persistently positive), at least 3 samples taking >12 hours apart.
• Endocardium is involved: valvular regurg, positive echo showing abnormality

Minor

• Predisposition (IVDU, cardiac lesion)
• Fever >38
• Vascular/ immunological signs
• Positive blood culture not meeting major criteria
• Positive echo not meeting major criteria

Question 6

Investigations for endocarditis (5)

Answer 6

Blood culture
- At least 3 sets, taken at different time, from different sites at peak fever.

Echocardiogram (transoesophageal more sensitive)
- Can reveal vegetation, degraded valves

Blood tests

• FBC, CRP, U+Es, LFTs, Mg2+
• Anaemia, leucocytosis, raised CRP?

Urinanalysis

• Rule out UTI
• Microhaematuria

CXR
- Cardiomegaly

Question 7

Management of endocarditis

Answer 7

Make haemodynamically stable

• Fluids, oxygen if septic
• Correct anaemia

Antibiotics- dependant on causative agent

Severe sepsis/ prosthetic valve/ IVDU

• Vancomycin IV
• Gentamicin BD
• Rifampicin PO BD

Native valve/ indolent
- Amoxicillin IV
+ Gentamicin BD

Penicillin allergy

• Vancomycin IV
• Gentamicin

Question 8

Common causative agent of infective endocarditis

Answer 8

IV drug users/ Most common
- Staph aureus

Developing world, no risk factors
- Strep. viridans

Prosthetic valves
- Staph epidermis (coagulase negtive)