Endocarditis

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Introduction

 

 

The Case of...

a simple case introducing clincial presentation and calling for a differential diagnosis to get students thinking.

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Causes and Risk Factors

Rheumatic fever used to be most common cause.

Congenital heart disease is now the most common.

 

 IVDU:

  • S aureus
  • S viridans
  • GNR

nonIVDU:

  • S viridans
  • S aureus
  • enterococcus

prosthetic (< 6 mo) - acquired at time of surgery

  • S epidermidis
  • S aureus
  • GNR

prosthetic (> 6 mo):

  • S epidermidis
  • Streptococcus
  • S aureus
  • Enterococcus

HACEK

  • Hemophilus
  • Actinobacillus
  • Cardiobacterium
  • Eikenella
  • Kingella

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Pathophysiology

 

 

used with permission, wikimedia

Grow in eddies; these are most commonly near the valves.

 

 

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Signs and Symptoms

A low-grade fever is the most common symptom, often on its own.

Janeway lesions and splinter hemorrhages.

Duke's Criteria - 2 major, or 1 major and 3 minor, or 5 major

Major

  1. Bacteremia with a pathogen known to cause IE
  2. vegetations on echo and new regurgitant murmur

Minor

  1. septic emboli: Janeway lesions, infarcts
  2. immune manifestations
  3. previous IE
  4. risk factors

 

  • history
  • physical exam

History

 

Physical Exam

 

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Investigations

  • lab investigations
  • diagnostic imaging

Lab Investigations

Bloodwork includes:

  • CBC
  • ESR, CRP

Do at least three sets of blood cultures, separated by time.

 

Urinalysis, as IE can often cause renal involvement. Look for signs of glomerulonephritis or emboli.

Diagnostic Imaging

Echocardiography can be done transthoracically or transesophageallu

 

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Differential Diagnosis

 

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Treatments

Antibiotic treatment will depend on the source, identified via culture.

Vancomycin + gentamycin are appropriate for emperic therapy.

Valve replacement may be indicated in patients with substantial, intractable growth of vegetation.

 

 

 

 

Consequences and Course

The most serious complications include emboli and mycotic aneurysms, leading to cerebral, splenic, or bowel infarction.

Valvular regurgitation can lead to congestive heart failure. Abscess can lead to electrical deregulation and arrhythmia.

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The Case of...

Case #2 - a small story wrapping it all up and asking especially about management.

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Additional Resources

 

 

 

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Topic Development

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