Viva - Infective Endocarditis Flashcards
Define Infective Endocarditis
Microbial infection of a native or prosthetic heart valve
OR the mural endocardium
This leads to formation of vegetations and tissue destruction
Has a propensity for haematogenous spread, therefore is a multi system disorder
How can IE be divided
Acute - fulminant course over days to weeks, due to S.aureus and results in spread
Subacute - slowly over weeks to months and less likely to cause metastatic infection
Risk factors for IE
Prosthetic valves IVDU Congenital heart disease Hx of endocarditis Damaged valves e.g rheumatic fever
Describe the clinical manifestation of IE
Non specific - weight loss, anorexia, neight sweats, malaise, nausea, vomiting.
Valvular involvement - murmur, failure due to valvular incompetencce
Bacteraemia - fever, CRP
Septic emboli - spleen, kidney, heart, brain
Immune complex formation
How do the septic emboli present
Splenic - LUQ pain, left side pleural effusion, rub
Renal - infarction, hametauria, flank pain
Coronary - MI / arrythmias
Cerebral - focal neurology, stroke
Pulmonary - breathlessness, RH involvements
Janeways lesions (macular plaques on palms
Splinter haemorrhages
How does immune complex formation present
Interstitial nephritis or glomerularnephritis due to deposition in the kidney
Immune mediated synovitis, MSK
Immune mediated myocarditis - palpitation
Oslers nodes - deposition in hands and feets
Roth spots - retinal haemorrahge
Causative organisms in native valves
Gram Pos bacterai - S.Aureas
Native valve;
Streptococci
Staph aureaus - MSSA in community IE
MRSA - nosocomial infection, wound infection, lines
Enterococci
HACEK
Haemophillus,
Actinobaccilus
Cardiobacterium hominis
Kingella
Rare
Q fever - rickettsia
Mycoplasma
Legionella
Fungal and pseudomonas in IVDU
causitive organisms in prosthetic valves
Early or late
Early - S.aureus
Enterococci
Fungi, candida, aspergillus
Coag neg staph
Late - s. aureus
Coag neg staph
Streptococci
Enterococci
How are is diagnosed
Modified duke criteria which are baed on micro/clinical or echo findings
Dukes clinical criteria
2 major
1 major 3 minor
5 minor
Dukes clinical criteria, Major
Blood culture positive for IE with 2 seperate blood cultures or a single positive culture for Coxiella burnetii or antiphase I IgG antibody titre > 1:800
Endocardial involvement:
Abscess, new partial dehiscience of a prosthetic valves
New valve regurgitation
Echo positive : oscilating intracardiac mass or valves
Dukes clinical criteria, minor
1) Predisposition or predisposing heart condition or IVDU
2) Fever, temp>38
3) Valve phenominae - Major arterial emboli
Septic pulmonary infarcts
Mycotic aneurysm
Intracranial haemorrhages
4) immune pnenomena
Oslers, Roth, Positive Rh Factor
5) Microbiology - blood culture not meeting major criteria
Dukes patholigcal criteria
Micro-organism - culture or histology in a vegetation or vegetation that embolised or intra-cardiac absess
Pathologic lesion - confirmed by histology
How to treat
Resus and supporitve care
Ix - TTE, TOE better image quality ECG, Bloods including inflam markers and renal Urinalysis CXR
3 Aggressive Abx AFTER blood cultures
3 sets of bloods of cultures from different sites
Micro advice
Empirical - fluclox and gent, adjust to sensitivity
Prolonged tx
Cardiac surgery
When to do heart surgery
Aortic stenosis or regurg leading to failure Valve dehiscience Myocardial abscess or fistula Fungal High risk of emboli (vegetation > 10mm) Persistant cultures despite tx
