Infective endocarditis patterns vs Sterile endocarditis patterns
How to tell Infective endocarditis patterns and Sterile endocarditis patterns apart when a board question makes them look alike.
Fever/positive cultures point to infective endocarditis; cancer/SLE with sterile culture-negative vegetations points to marantic or Libman-Sacks.
Side by side
Acute S. aureus endocarditis is aggressive and can affect normal valves, often with IVDU/tricuspid disease; subacute viridans endocarditis affects damaged valves after dental/oral bacteremia; HACEK, Bartonella, and Coxiella can be culture-negative or slow-growing.
Marantic/nonbacterial thrombotic endocarditis has sterile platelet-fibrin vegetations with malignancy or hypercoagulability; Libman-Sacks has sterile verrucous vegetations with SLE/antiphospholipid syndrome.
Infective endocarditis is microbial colonization of valve endocardium with bacteremia, vegetations, emboli, and immune phenomena.
Sterile endocarditis reflects thrombotic or immune-mediated vegetations without active valve infection.
Fever, positive blood cultures, new murmur, echo vegetation, septic emboli, Janeway lesions, Osler nodes, and Duke criteria support infective endocarditis.
Negative cultures, embolic phenomena, adenocarcinoma or SLE/APS background, and sterile vegetations support marantic or Libman-Sacks endocarditis.
The trap
Culture-negative endocarditis can still be infectious, especially after antibiotics or with HACEK, Bartonella, or Coxiella, so clinical context matters.
The repair move
For valve vegetations, separate infected bacteremic vegetations from sterile thrombotic or autoimmune vegetations.
Try a free question
CoreA person who injects drugs has fever, new tricuspid murmur, positive blood cultures for S. aureus, and septic pulmonary emboli. Which pattern is most likely?
Show answer and explanation
Answer: A. Acute infective endocarditis. IV drug use with acute fever, tricuspid involvement, S. aureus bacteremia, and septic pulmonary emboli supports acute infective endocarditis.
Why the other choices are tempting
- B. Subacute viridans endocarditis classically follows oral bacteremia on damaged valves.
- C. Marantic endocarditis is sterile and linked to malignancy/hypercoagulability.
- D. Libman-Sacks endocarditis is sterile and linked to SLE/APS.
- E. Rheumatic valvulitis follows group A strep immune disease.
Flashcards
Tap a card to flip it.
What organism causes acute aggressive endocarditis on normal valves?
Staphylococcus aureus can cause acute aggressive endocarditis on normal valves.
What organism classically causes subacute endocarditis after dental bacteremia?
Viridans streptococci classically cause subacute endocarditis on damaged valves after dental/oral bacteremia.
Quick answers
What is the fastest way to tell Infective endocarditis patterns from Sterile endocarditis patterns?
Fever/positive cultures point to infective endocarditis; cancer/SLE with sterile culture-negative vegetations points to marantic or Libman-Sacks.
What is the key clue for Infective endocarditis patterns?
Acute S. aureus endocarditis is aggressive and can affect normal valves, often with IVDU/tricuspid disease; subacute viridans endocarditis affects damaged valves after dental/oral bacteremia; HACEK, Bartonella, and Coxiella can be culture-negative or slow-growing.
What is the key clue for Sterile endocarditis patterns?
Marantic/nonbacterial thrombotic endocarditis has sterile platelet-fibrin vegetations with malignancy or hypercoagulability; Libman-Sacks has sterile verrucous vegetations with SLE/antiphospholipid syndrome.
What is the common trap with Infective endocarditis patterns vs Sterile endocarditis patterns?
Culture-negative endocarditis can still be infectious, especially after antibiotics or with HACEK, Bartonella, or Coxiella, so clinical context matters.