Infective endocarditis Flashcards
How is IE diagnosed
Dukes criteria - pathologicla or clinical
What is endocarditis
Infection and inflammation of endothelial surface of heart by microorganism
Pathogenesis of endocarditis
Tubulent blood flow -> dmaage smooth surfaces - accumulation of platelets/fibrin/leucocytes -> infected by any circulating microorganisms and form vegetation
What is vegetation
Infected mass attached to endocardial structure or on implanted intracardiac material
Vegetation on ECHO
Oscillating or non oscillating Intracardiac mass or other endocardial structures
Abscess appearance on ECHO
Thickened, non homogenous pervalvular area w echodense or echolucent appearance
What is a pseudoaneurysm and how does it look on ECHO
Perivalvular cavity communicating within cardiovascular lumen
Pulsatile perivalvular echo-free space with colour doppler flow detected
What is a perforation and how does it look on ECHO
Interruption of endocardial tissue continuity traversed by colour doppler flow
Can create a fistula
Valve aneurysm what is
Saccular outpuching (bulging on ECHO) of valvular tissue
How does dehiscence of prosthesis appear on ECHO
Paravalvular regugitation identified by TTE/TOE with or without rocking motion of prosthesis
Risk factors for IE
Any type of structural HD
RHD, mitral valve
Prosthetic valves, cardiac devices
Congenital HD
IVDUs
HIV
Extensive health care system contacts eg hospital interventions and time spent in hosptial
Bacterial causes of IE most common
Staoh ir strep 80% time
S.aureus, coagulase engative staph - rising due to hospital related infection
Enterococci - 3rd highest cause, related to healthcare contact
Gram negative and fungal pathogens rare but v severe and poor outcomes
Why cant always trust blood cultures in IE
10% patients have negative blood culture - either given antibiotics before or fastridious microorgansisms difficulty to isolate
List of causes of IE negative blood culture
Coxiella burnetti (livestocl, Q fever cause)
Bartonella spp (alcohol, homeless)
Brucella spp (livestock or abbattoirs)
Tropheryma whipplei
Brucella spp (middle east, unpasteurised diary)
Bartonella henseale (cats)
Aspergillus spp (healthcare contact w prosthetic valve)
Clinical history of IE why varies
Dependent on causative oraganism, cardiac disease etc -> varying presentation
Most common features of IE
Malaise, fever, cardiac murumurs
Symptoms that can signify endocarditis
Malaise, fever, new murmurs
Haematuria, Splenomegaly,
HF, petechiae ,arthralgia, cerbral emboli, mycotic aneurysm, clubbinng, oslers nodes, splinter haemorrhages, janeway lesions, Roth spots, conjunctival haemorrhages,
What does L sided IE cause
Infected emboli travelling through arteries systemically except lungs
What does R sided IE cause
Infected emboli -> lungs
Immunological manifestations of IE
Oslers nodes
Immune complex deposition glomerulonephitis
Systemic - Rf raised
What are oslers nodes
Arteriolar intimal proliferation w extension to venules and capillaries and may be accompanied by thrombosis and necrosis
Immune complexes within lesions
Investigation for IE
Bloods - inflam markers - CRP, ESR, WCC, Plts, U+Es, LFTs
Blood cultures
ECHO - TTE or TOE (more sensitive, can ick up emboli <5mm)
Blood cultures required for IE
3 sets within a period of time each 1-6 hrs apart
2 sets within 1 hr if septic patient from different sites
Why dont wait for temperature spike in IE
Bactaraemia is constant in IE
Treating endocarditis
National guidelines
4-6 weeks (L side longer) in hosptial - Outpatient when available
2 weeks if v sensitive
IV fo duration
Indicaitons for surgery with IE
Heart failure
Uncontrolled infection
Prevention of embolism
What is counted as uncontrolled infection in IE?
Abscess, aneurysms, fistula, enlarging vegetation despite antibiotics (risk of infected emboli high)
Persisting + blood cultures despite appropriate antibiotic
PVE caused by staph or non-HACEK gram - bacteria
Infection caused by fungi or multiresistant organisms
What surgical criteria for preventing embolism in IE
Aortic or mitral valve NVR or PVE w persitent vegetations >10mm after one or more embolic episode despite antibioticsn
Aortic or mitral NVE w vegetations >10mm ass w severe valve stenosis or regurg and low operative risk
Aortic or mitral NVE or PVE w isolated large vegetations >15mm
Aortic or mitral NVE or PVE w isolated v large vegetations >30mm
HF signs in IE
Aortic or mitral NVE/PVE
Severe acute regurgutatuon, obstruction or situal -> refractory pulmonary oedema or cardiogenic shock OR symptoms of HF, ECHO signs of poor haemodynamic tolerance
Prognosis for IE
100% death if no treatment
optimal treamtnet 20-25% die of IE
Predictors of poor otuomes IE
Older, prosthetic valve, diabetes, comorbiditiy
Clinical comps - HF, rneal failure, >moderate area ischaemic stroke, brain haemorrhaege, septic shcok Micororgansism - staph aureus, fungi, non-HCAEK gram negative bacteria
ECHO findings
ECHO findings that suggest poor prognosis
Periannular comps, severe L sided valve regurgitiation
Low left ventricular ejection fraction
Pulm HPTN
Large vegetations
Sev prosthetic valve dysfunction
Premature mitral valve closure or other signs of elevated diastolic pressure
Pathological criteria for IE
Micororganisms demostrated by culture or histology
Need a biopsy of vegetation
Clinical criteria for IE how many need confirmed vs possible
Confirmed:
2 major criteria
1 major criteria and 3 minor criteria
5 minor criteria
Possible:
1 major criteria and 1 minor criteria
3 minor criteria
Rejected IE diagnosis criteria
Alternate diagnosis
Resolution with anitbitoic therapy <4 days
No pathologic evidence of IE at surgery or autopsy w antibiotics <4 days
What is the new criteria for IE
ESC 2023
Major criteria for endocarditis Dukes
+ blood culture for IE
Evidence of endocardial involvement
Evidence of endocardial involvement DUKES criteria
+ ECHO for IE
New valvular regurgitation
Vegetation
abscess
new partial dehiscence of prosthetic valve
What need for + blood culture IE major criteria
typical microorganism from two separate cultures >12hrs apart OR 3 or 4 cultures of blood - first and last 1 hr apart
Eg separated in time and space
Must be one of:
Viridans strep, strep bovis (ganolyticus - ass bowel cancer) or HACEK group OR CAP S.aureus, enterococci without obvious primary source infection
Single positive culture for C.burnettu or antiphase 1 IgG antibody titre >1:800
mINOR dUKES CRITERIA FOR ie
Predisposition
Fever >38.0
Vascular phneomena
Immunological phenomena
Microbiological phenomena
PCR - broad range of 165
ECHO findings - consistent w IE but not major criterion
What are predispositions in DUKES
Predisposing heart condition or IVDU
Vascular phenomena counting as minor dukes criteria for IE
Major arterial emboli, septic pulmonary infarcts CXR, mycotic aneurysm, IC haemorrhage, conjunctival haemorrhage, janeways lesions
Immunological phenomena minor dukes criteria IE
Glomerulonephritis, oselers nodes, roth spots, Rf
Microbiological phenomena minor dukes criteria IE
+ blood culture but doesnt meet major criterion or serologuical evidence of activa=e infection with organism consitent with IE
Dukes criteria vs ESC 2023 xriteria
Imaging in major criteria
Dukes - ECHO
ESC - Cardiac CTs or nuclear imaging
Removed ECHO findings from minor criteria
Removed broad range PCR from minor criteria
What bacteria causing IE blood culture sample only need one for
C burnetti
What are oslers nodes
Red v painful spots on pulps of fingers and toes pale in middle
Cardiac risk factors for endocarditis
Prev IE
Valvular HD stenosis or regurg
Hypertrophic CM
Prosthetic heart valve
Central venous catheter or arterial catheter
Transvenous cardiac implantable electronicdevice
Congnital HD
Non cardiac risk factors for IE
Central venous catherer
IVDU
Immunosupression
Recent dental or surgical procedures
Recent hospitalisation
Haemodilaysis
What are janeway lesions
maculopapular on palms or soles non painful few mms
What organisms can mean no blood culture +
Fastidious gram negative bascilli - HACEK group eg aggregatibacter aphrophilus
Others - Haemophilus, caerdiobacterium hominis, eikenella corrodens and kingella kingae
Why use oral antibiotics instead of IV endocarditis
Hospital stay - increased risk of hospital complications
After patient stable rare to get bad again
What is POET
Partial oral antibiotic endocarditis therapy
Stabilised endocarditis patietns treated initially with IV antibiotics
Then test continuing w oral or IV
Method of POET
Stable adults receiving IV antibiotics for L sided endocarditis, native or prosthetuic valves, fulfilled modified Duke critiera, + blood cultures for strep, enterococcus, staph aureus, coag negative staph
Antibiotics w moderate to high bioavailability
Put half on combined PO antibiotic therapy
What did POET record (events)
All cause mortality, unplanned cardiac surgery, embolic events, relapse of bactaraemia for 6 months A
POET study finding
No significant statistical differnece between oral and IV antibiotics
Side effects from PO
Allergy, bone marrow suppression, GI side effects
Conclusins of POET study
Efficacy and safety of shifting to oral antibiotic treatment was non inferior to continued IV antibitoic treatment
Oral antibiotics may safely be administered during half the recommended antibiotic treatment periods - can be oupatient - reduce hospital stays
May apply to >50% endocarditis patients in future
What cardiac conditions are not risk factors for IE
Isolated ASD
Fully healed VSD, PDA
Management of IE
Blood culture and ECHO/imaging -> empirical broad spec IV antibiotics
Adjust anitbiotics according to sensitivities and complications treating -> cardiac surgery or
Organisms would match with recent dental extraction IE
Viridans strep - mitis group
Organisms would match with recurrent UTIs IE
Enterococcus faecalis
Organisms would match with hickmans line IE
Candida albicans
Staph aureus, coag negative staph
Organisms would match with IVDU IE
Staphg aureus, candida albicans
Reasons for blood culture negative IE
Intracellular pathogens eg legionella, brusella, bartonella, mycoplasma
Specific culture needed eg mycobacteria
Long incubation periods - routine culture doesnt work
16s RNA PCR for bacteria, 18s RNA PCR for fungi
What imaging pathway do for endocarditis first
TTE
If +, poor quality or theres a prosthetic valve IC device -> TOE
If negative but high clinical sus -> TOE
Repeat TOE in 7-10 dyas if negative but still high clinical sus
What antibiotic can reduce duration of treamtnet for IE
Gentamicin increased bactericidal acitivity due to syndergism
When caused by penicllin sensitive strep
Why differnet treatment for prosthetic HV
Biofilm risk - need penetrating agents
6 weeks antibiotics vs 4 for native valves
MRSA IE treat
Vancomycin, dactomycin
HACEK group what stand for
Haemophilus
Aggregabactae
Cardiobacterium
Eikenella
Kingella
Fastidious gram negative
First line treatment for HACEK
Ceftriaxone
CAnt use amoxicillin as some produce beta lactamases
Septic/unstable patients with IE treatmet if risk factors for resistant bacteria
Vancomycin, meropenem
If none - vancomycin with gentomycin
Otherwise amoxicillin +/- gentomycin
Pending blood cultures or negative - vancomycin, gentamycin, rifampacin - for biofilm
Staph IE treat
Fluclox, vancomycin, gentomycin, rifmapacin
Strep IE treat
Benzylpenicillin, ceftriazone, gentamizin, vancomycin, teicoplanin
Enterococcal IE treat
Prolonged treat in combo
gentomycin or ceftriazone
Amoxicillin
Penicillina
Vancomycin, teicoplanin
Fungal IE treat
Low threshold for surgery
Look for complications
Fluconazole, variconazole, amphotericin, itaconazole
Remove lines
HACEK manageent IE
Cephalosporin or amoxicillin
Gentamicin
Ciprofloxacin
Complications of IE
Neurological
Infective aneurysms
Splenic complications
Myocarditis, pericarditis
Heart rhythm and conduction distubrances
Osteoarticular infection
Follow up for IE
Monitor for 1 year
Development HF
end treatment TTE
Recurrence
Rehabilitation, psych support
Ideal cultures for IE
three sets from peripheral sites >6 hours between them if chronic or subacute
If acute from different sites with as ling between as can leave clinicaly safely
When do you start antibiotics with IE
Chronic - wait for culture senstivities before commence
Septic/acute - commense broad spectrum while waiting cultures
FROM JANE signs/symptoms of IE
Fever
Roth spots
Oselers nodes
Murumur
Janeway lesion
Anaemia
Nail haemorrhage
Emboli
