Endocarditis: bacterial

Buy now to access the full article, existing subscribers login

Sections available in full article Introduction, Presenting signs, Acute presentation, Sex predisposition, Breed predisposition, Cost considerations, Special risks (e.g. anesthetic), Pathogenesis, Etiology, Predisposing factors, Pathophysiology, Timecourse (incubation, duration), Diagnosis, Presenting problems, Client history, Clinical signs, Diagnostic investigation, Confirmation of diagnosis, Gross autopsy findings, Histopathology findings, Differential diagnosis, Treatment, Initial symptomatic treatment, Standard treatment, Subsequent management, Sequelae, Prognosis, Expected response to treatment, Reasons for treatment failure, Sources, Publications, Vetstream contributor(s),
Contributors Dr Serena Brownlie BVM&S PhD CertSAC MRCVS
Mr Mark Rishniw BVSc MS DipACVIM

Introduction

  • Rare.
  • Valvular (usually mitral and aortic valves). Less commonly mural.
  • Cause : usually history of previous septic focus or febrile illness (but not always).
  • Signs : episodic illness with pyrexia, multi-system involvement, and variable heart murmurs.
  • Diagnosis : history, signs, ultrasonography.
  • Treatment : antibiotic.
  • Prognosis : guarded.

Diagnosis

Clinical signs

  • Pyrexia (may be intermittent).
  • Heart murmur - systolic or diastolic, variable, may be intermittent, not always present.
  • Focus of infection may be evident.
  • Joint heat, pain, effusions apparent.
  • Signs of involvement of more than one body system.

Diagnosis

Differential diagnosis



Pyrexia of unknown origin
  • No major differentials for the typical presentation of coordination of clinical signs:
    • AlI disease secondary to endocarditis.
    • Neoplasia Pericardium: neoplasia (heartbase tumor).


For 2-D echocardiographic abnormality
  • Valvular endocardiosis Heart: mitral valve degenerative diseaseEndocardiosis: tricuspid valve.
  • Aortic stenosis Aortic stenosis.

Sequelae

Prognosis



Small valvular vegetations or non-vegetative endocarditis
  • Respond well to appropriate long-term therapy (>6 weeks).
Large and long-standing valvular vegetations
  • A constant source of seeding bacteremia.
  • Rarely rendered sterile even with continued antibiosis.
  • Likely to be hemodynamically significant → aortic insufficiency → volume overloaded left ventricle → myocardial failure.
  • Eventually lesion → stenosis → pressure overload on failing left ventricle → myocardial failure.

Expected response to treatment

  • Control of pyrexia and clinical status. If achieved, same antibiotic should be continued despite the absence of large vegetations.
    Change antibiotic or add another antibiotic if pyrexia continues and/or clinical status deteriorates beyond first 24 hours of initial antibiotic.

Reasons for treatment failure

  • Long-standing lesion.
  • Large vegetation.
  • Septic emboli elsewhere of clinical significance.
  • Non-specific diagnosis and only short-term antibiotic treatment given.
  • Indiscriminate use of glucocorticoids in bacteremic patients.

Sources

Publications

Refereed papers

  • Recent references from PubMed.
  • Peddle G & Sleeper M M (2007) Canine bacterial endocarditis: a review. JAAHA 43 (5), 258-263 PubMed.
  • Sykes J E, Kittleson M D, Pesavento P A, Bryne B A, MacDonald K A & Chomel B B (2006) Evaluation of the relationship between causative organisms and clinical characteristics of infective endocarditis in dogs: 71 cases (1992-2005). JAVMA 228 (11), 1723-1734 PubMed.
  • Boswood A (1996) Resolution of dysrhythmias and conduction abnormalities following treatment for bacterial endocarditis in a dog. JSAP 37 , 327-332.
  • Bennett D, Taylor D J (1988) Bacterial infective arthritis in the dog. JSAP 29 , 207-230.
  • Ellison G W, King R R, Calderwood-Mays M (1988) Medical and surgical management of multiple organ infarts, secondary to bacterial endocarditis in a dog. JAVMA 193 , 1289-1291.

Sample content only, to unlock the full article login or buy now

Loading...