Infective Endocarditis Flashcards
What can be infected in IE
Endocardium Heart valve Septum Chordae tendinae Intra-cardiac devices
What are cardiac RF for IE
Intra-cardiac device / procedure Prosthetic valve Rheumatic HD Valve disease - AS, MVP, MR, MS Congenital - Biscuspid aortic valve / VSD - If have VSD and culture staph must screen for IE HCM Previous IE
What are non cardiac RF
Immunocompromised - DM - HIV IVDA Piecing Dental IV lines Haemodialysis Malignancy Chronic skin / dermatitis / wound Alcoholic cirrhosis Renal failure GI lesion Organ transplant
What are common organisms on blood culture
S.Aureus = most common
Strep viridans
Enterococci vaecalis - prostate / UTI - high mortality
S.epidermidis - common after surgery as contaminant
Strep bovis
- If found must screen for colorectal cancer
What are common organisms if blood culture -ve
Fungi - candidia / Aspergillis Gram -ve HACEK - H.influenza - EXAM Chlamydia Bartonella Coxiella burnetti Brucella
Non-infective
SLE
Malignancy
Hyper-coagulable
What are non-specific symptoms then signs of end organ damage
Fever - don't always have and may be low grade Rigors Malaise Fatique Weight loss Night sweats
Organ
- Anaemia
- Splenomegaly - may be painful if infarction
- Renal infarction / AKI
- Congestive CF - SOB / palpitations
What are immunological signs
GN - haematuria in 70%
Roth spots - retinal haemorrhage on fundoscopy (may need ophthalmology review)
Osler node - painful raised spots
Splinter haemorrhage
What are vascular signs
Emboli from vegetations Vasculitis rash Splenomegaly Clubbing Janeway lesion - flat non tender Petechiae or purpura
What does emboli cause
Focal neuro signs
PE
Peripheral emboli - renal failure
When can signs be absent
Elderly
Immunocompromised
Ax
What type of ECHO is done
TTE
If TTE -ve but high suspicion = TOE
If TTE +ve then TOE for complications
What is suggestive of IE
New murmur
- Typically pan systolic from mitral
Fever >1 week
When should you have a high degree of suspicion
PUO New murmur IE causative agent cultured Prosthetic Previous IE Congenital heart Immunocompromised IVDA
Who is more likely to have a fungal infection
Immunocompromised
IVDA
Prosthetic
How do you investigate IE
Blood culture - 3 sets in 24 hours from different spots 2 sets within 1 hour if severe sepsis Need to get one from line if in situ PCR / serology for culture -ve FBC, U+E, LFT, CRP, Mg
What does bloods show
Normocytic normochrmic anaemia Thrombocytopenia Raised WCC / CRP Raised Ig Decreased C3 Abnormal U+E / LFT
What are other tests
Urinanalysis / dip - Always look as emboli could cause NVH ECG CXR ECHO CT
What does urinalysis look for
Protein / haematuria
What does ECG look for
Conduction defects
Heart block
What does CXR look for
Signs of HF
Pulmonary abscess
Emboli
What type of ECHO is 1st line
TTE to visualise vegetations but normally TOE best
When do you use TOE
If TTE +Ve to look for complications, abscess and measure vegetations
If high clinical suspicion and TTE -ve
Repeat to asses Rx and look for complications
What do you do a CT for
Look for emboli
Where are the majority of vegetations found
Mitral valve
Aortic
Where in IVDA
Tricuspid so more common real life
What does everyone with a S.Aureus bacteraemia get
TTE ECHO
What do you need to Dx IE
2 major Duke criteria
1 major and 3 minor
5 minor
What is major Duke’s criteria
2 + specific blood culture
- S.aureus
- S.viridans
- S.bovis
- Enterococci
- HACEK group
Evidence of endocardial involvement on ECHO
- Vegetation
- Abscess
What are Duke’s minor criteria
Predisposing heart IVDA Fever >38 Vascular Immunological Microbiology that doesn't meet major Serology with organism consistent with IE that is culture -ve
How do you treat IE
IV antibiotics for 4-6 weeks after culture
What is blind treatment when no organism cultured
Gentamicin
Amoxicillin / flucloxacillin
What do you do if allergic / MRSA
Gent
Vanc
Rifampicin
What do you do for Staph
Flucloxacillin
Vanc + rifampicin if allergic / MRSA
What do you do if prosthetic Staph
Use all 3
How do you treat strep
Benzypenicillin
What do you do if allergic
Gentamicin
How do you treat enterococcus
Amoxicillin / Benzypenicillin
Gentamicin
Vancomycin if allergic
What do you do for HAEK gram -ve
Ceftriaxone
What do you do for prosthetic valve
Add rifampicin
What do you do for fungal infections
Dual anti-fungal for life
Valve replacement
How do you monitor
FBC, U+E, CRP daily
ECG 1-2 days
Weekly ECHO
When is urgent surgery indicated / valve replacement
Severe valve damage >10mm Large vegetations Early infection with prosthetic Aortic abscess lengthening PR Resistant infection / overwhelming sepsis CF - resistant oedema/. shock Recurrent emboli Fungal Pregnant
Who gets prophylaxis
Not recommended
What suggests poor outcome
S.Aureus Fungal Heart failure Co-morbid Prosthetic valve Low complement CAn't identify organism IDDM CVA
What are the complications of IE.
LVF = most common Mitral regurgitation Prosthetic valve dysfunction Emboli / stroke HF Uncontrolled infection / sepsis Fistula formation Abscess AV block AF Renal failure
What else may patient present with
OM SA Pneumonia Neuro GN Vasculitis Meningiitis
What does septic emboli suggest
IVDA
What needs to be +ve for definite Dx
All 3 blood cultures
DDX
TB
Malignancy
Vasculitis
When do you do TTE
All S.aureus bacteraemia
What do you do if TTE -ve but high suspicion
TOE
What are atypical presentation
Septic emboli
- Young IVDA who presents with Sx of stroke / spinal pain / renal failure
RF vs IE
IE = alpha haemolytic (Strep viridian) IE = mitral regurgitation RF = beta haemolytic RF = mitral stenosis common
