What are the major criteria for diagnosing infective endocarditis according to the modified Duke criteria?
Positive blood cultures with a typical organism and evidence of endocardial involvement
Endocardial involvement may include vegetations seen on echocardiogram.
How many major criteria are needed for a diagnosis of infective endocarditis?
Two major criteria, one major and three minor criteria, or five minor criteria.
What is a minor criterion that supports the diagnosis of infective endocarditis?
History of intravenous drug use.
Minor Criteria
* Fever
* Risk factors
* Roth spots, Osler nodes, Janeway lesions, splinters
What are Janeway lesions?
Non-tender vascular lesions on the palms and soles.
What are Osler nodes?
Painful, violaceous nodules usually found on the fingers or toes.
What are Roth spots?
Pale-centered retinal hemorrhages seen in some cases of endocarditis.
What is the significance of Roth spots in infective endocarditis?
They represent a minor criterion and are immunologic phenomena resulting from immune complex deposition.
What type of bacteria is Streptococcus gallolyticus?
A group D streptococcus that can cause subacute bacterial endocarditis.
What is Enterococcus faecalis known for in the context of endocarditis?
It can cause endocarditis particularly after genitourinary or gastrointestinal procedures.
What is the common cause of prosthetic valve endocarditis?
Staphylococcus epidermidis.
What is the main distinguishing feature of Staphylococcus aureus?
It is coagulase-positive.
What is nonbacterial thrombotic endocarditis (NBTE)?
A condition where vegetations develop on cardiac valves consisting mostly of platelets and fibrin, without bacteria.
What are the common locations for vegetations in NBTE?
Mitral and aortic valves.
What is the typical presentation of subacute bacterial endocarditis?
Heart murmur, fevers, joint pains, and elevated erythrocyte sedimentation rate.
How does acute bacterial endocarditis differ from subacute endocarditis?
Acute endocarditis has a rapid onset and is associated with more severe symptoms.
What is culture-negative endocarditis?
Endocarditis where echocardiographic evidence is present but blood cultures are negative.
What bacteria is commonly associated with culture-negative endocarditis in patients exposed to farm animals?
Coxiella burnetii.
What is the main manifestation of chronic Q fever?
Endocarditis.
What is the most common cause of fungal endocarditis?
Candida albicans.
What distinguishes the vegetations in Libman Sacks endocarditis?
They do not contain bacteria and are non-infectious.
What is the primary vector for Bartonella quintana, which can cause culture-negative endocarditis?
Lice.
What are the symptoms of body louse infestation?
Itching.
What type of hemolysis is characteristic of Enterococcus?
Gamma hemolysis.
Fill in the blank: Staphylococcus aureus is __________ positive.
coagulase
