Highlighter is on. Drag to highlight text. Click a highlight to remove it.
ALL / Cardiology
Infective endocarditis: aetiology
Infective endocarditis: aetiology
The strongest risk factor for developing infective endocarditis is a previous episode of endocarditis. The following types of patients are affected:- previously normal valves (50%, typically acute presentation)
- the mitral valve is most commonly affected
- rheumatic valve disease (30%)
- prosthetic valves
- congenital heart defects
- intravenous drug users (IVDUs)
- e.g. typically causing tricuspid lesion)
- others: recent piercings
Causes
- Staphylococcus aureus
- now the most common cause of infective endocarditis
- particularly common in acute presentation and IVDUs
- Streptococcus viridans
- historically Streptococcus viridans was the most common cause of infective endocarditis. This is no longer the case, except in developing countries
- technically Streptococcus viridans is a pseudotaxonomic term, referring to viridans streptococci, rather than a particular organism. The two most notable viridans streptococci are Streptococcus mitis and Streptococcus sanguinis
- they are both commonly found in the mouth and in particular dental plaque so endocarditis caused by these organisms is linked with poor dental hygiene or following a dental procedure
- coagulase-negative Staphylococci such as Staphylococcus epidermidis
- commonly colonize indwelling lines and are the most cause of endocarditis in patients following prosthetic valve surgery, usually the result of perioperative contamination.
- after 2 months the spectrum of organisms which cause endocarditis return to normal (i.e. Staphylococcus aureus is the most common cause)
- Streptococcus bovis
- associated with colorectal cancer
- the subtype Streptococcus gallolyticus is most linked with colorectal cancer
- non-infective
- systemic lupus erythematosus (Libman-Sacks)
- malignancy: marantic endocarditis
Culture negative causes
- prior antibiotic therapy
- Coxiella burnetii
- Bartonella
- Brucella
- HACEK: Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, Kingella)
+PassMedicine Notes
The strongest risk factor for developing infective endocarditis is a previous episode of endocarditis. The following types of patients are affected:
- previously normal valves (50%, typically acute presentation)
- the mitral valve is most commonly affected
- rheumatic valve disease (30%)
- prosthetic valves
- congenital heart defects
- intravenous drug users (IVDUs)
- e.g. typically causing tricuspid lesion)
- others: recent piercings
- Staphylococcus aureus
- now the most common cause of infective endocarditis
- particularly common in acute presentation and IVDUs
- Streptococcus viridans
- historically Streptococcus viridans was the most common cause of infective endocarditis. This is no longer the case, except in developing countries
- technically Streptococcus viridans is a pseudotaxonomic term, referring to viridans streptococci, rather than a particular organism. The two most notable viridans streptococci are Streptococcus mitis and Streptococcus sanguinis
- they are both commonly found in the mouth and in particular dental plaque so endocarditis caused by these organisms is linked with poor dental hygiene or following a dental procedure
- coagulase-negative Staphylococci such as Staphylococcus epidermidis
- commonly colonize indwelling lines and are the most cause of endocarditis in patients following prosthetic valve surgery, usually the result of perioperative contamination.
- after 2 months the spectrum of organisms which cause endocarditis return to normal (i.e. Staphylococcus aureus is the most common cause)
- Streptococcus bovis
- associated with colorectal cancer
- the subtype Streptococcus gallolyticus is most linked with colorectal cancer
- non-infective
- systemic lupus erythematosus (Libman-Sacks)
- malignancy: marantic endocarditis
- prior antibiotic therapy
- Coxiella burnetii
- Bartonella
- Brucella
- HACEK: Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, Kingella)
