Infective Endocarditis Flashcards
What is the definition of endocarditis?
Infection of the endocardium with formation of a vegetation resulting in damage to the cusps of valves
What are the risk factors for endocarditits?
- Previously normal valves,
- Rheumatic valve disease,
- Prosthetic valves,
- Congenital heart disease
- IVDU,
- Recent piercings,
- Age > 60,
- Male sex,
- Poor dentition
What are the different causes of IE?
- S.aureus (most common cause, especially in IVDU)
- S.viridans (found in mouth, commonly found in native valve endocarditis)
- Coagulase negative staph, eg, staph epidermidis (most common in prosthetic valve patients)
- Streptococcus bovis (associated with colorectal cancer)
- Non infective: SLE or malignancy
What are culture negative causes of IE?
HACEK: haemophilus, actinobacillus, cardiobacterium
Brucella
Bartonella
Coxiella burnetii
What are the symptoms of IE?
- Fever (If fever and new murmur then IE until proven otherwise)
- Night sweats,
- Anorexia,
- Weight loss
- Myalgia
- Less common: headaches, arthralgia, abdominal pain, cough, pleuritic pain
What are the signs of IE?
Systemic - Febrile, cachectic, clubbing, splenomegaly
Cardiac - Murmur, bradycardia (aortic root abscess tracks down AVN)
Vascular - septic emboli (splenic infarct, stroke), Janeway lesions (painless haemorrhagic lesions)
Immunological phenomena - Splinter haemorrhages, olser’s nodes (painful pulp infarcts), roth spots, glomerulonephritis
What is rheumatic fever?
Autoimmune response triggered by group A strep infection. It presents with fever, heart murmur and joint pain.
What is the Modified Dukes Criteria?
Used for diagnosis of IE. IE diagnosed if:
- Pathological criteria positive,
- 2 Major criteria,
- 1 major and 3 minor criteria,
- 5 minor criteria
BE FIVE PM
What is the pathological criteria
Positive histology or microbiology of pathological material obtained via autopsy or surgery.
What is the Modified dukes criteria major criteria?
- Two positive blood cultures showing typical microorganisms or three blood cultures showing less specific microorganisms or single positive blood culture for coxiella burnetti
- Positive ECHO (vegitations) or new valvular regurgitiation
What is the minor criteria in the modified dukes criteria?
- Fever > 38,
- Immunological phenomena (Roth spots, splinter haemorrhages or osler nodes)
- Vascular phenomena (septic embolis or janeway lesions.
- ECHO criteria which doesn’t meet major criteria
- Predisposing features eg, valvular disease, known IVDU.
- Microbiology evidence which doesn’t meet criteria for major criteria
How can IE be classified?
Acute - symptoms for less than 6 weeks.
Subacute - symptoms lasting from 6 weeks to 3 months.
Chronic - Symptoms lasting > 3 months.
What are the investigations for infective endocarditis?
Bedside - ECG, urine dip.
Bloods - routine and cultures
Imaging - ECHO, CT CAP to look for evidence of septic emboli
What is the blind management of infective endocarditits?
Native valve - amoxicillin +/- gent.
Prosthetic valve - vanc, gent and rifampicin
What is the management for S.aureus IE?
Native valve - Flucloxacillin. Second line is vanc and rifampicin. 4 weeks of treatment.
Prosthetic valve - Flucloxacillin, rifampicin and gentamicin. 6 weeks of treatment because of prosthesis