Endocarditis Flashcards
Define Infective Endocarditis?
Infection of the heart material. Can include endocaridum/valves/septa/chordae tendinae/intra-cardiac devices
What is non-infective Endocarditis and what causes it?
Non-Bacterial Thrombotic Endocarditis
The formation of a sterile Fibrin-platelet vegetation due to some disruption of the valve endothelium.
Turbulent Flow - Electrodes/Catheters - Rheumatic Carditis - Degenerative Disease - Local inflammation (~25% of cases)
How do we classify cases of endocarditis
Acute/Subacute/Chronic pattern
Also which side theyre on, what structure, if a valve is it native or prosthetic, if prosthetic is it early or late? (<1yr or >1yr)
How can Infective endocarditis be acquired?
- Via IVDA
- Community Acquired
- Nosocomial
- Healthcare Related but Non-Nosocomial
How do the IE organisms reach the circulation?
From:
Extra Cardiac Infection - Invasive Procedures - Gingival Disease - Daily livinig (e.g. brushing teeth & defecating)
What are the risk factors for IE?
Male (though women have worse prognosis Elderly Invasive Procedures recently IVDA Prosthetic Valves Any Heart Defect/Disease Diabetes AIDS Burns Immunocompromised
What are the symptoms of IE?
FEVER - MALAISE - FATIGUE
also chills - arthralgia - weight loss - headache
What are the clinical signs of IE?
General:
Pyrexia - CHF - New Murmur - Splenomegaly - Emboli - Anaemia
Vascular: Janeway Lesions (blood seeped into palms/soles) Splinter Haemorrhages Vasculitic Rash (feet, purple/red spots from burst capillaries)
Immunological:
Roth Spots (Retinal Haemorrhage)
Osler’s Nodes (Red raised painful spots of fingers, palms & soles)
Nephritis
When could the clinical signs be absent from IE?
In the elderly, immunocompromised or post antibiotic treatment
What does the mnemonic FROM JANE stand for?
Fever - Roth Spots - Oslers Nodes - Malaise - Janeway Lesions - Anaemia - Nephritis & Nail haemorrhages - Emboli
What details about a patient would give a high suspicion of IE?
Any of:
Unexplained fever - New Murmur - Known IE causin organism detected - New conduction disorder.
Also we suspect anyone with Prosthetic valves - Previous IE - CHD - New conduction Disorder - IVDA - Immunocompromised
What investigations are done on a suspected IE case?
FBC(neutrophilia)/CRP/ESR U + Es Blood Cultures Urinalysis ECG CXR ECHO
What are we lookin for with a FBC, CRP & ESR>
Any markers of infection/inflammation.
E.g. neutrophilia, a high CRP and high ESR
What are we looking for in the Urea + Electrolytes?
Analyse kidney function for nephritis & sepsis
What are we looking for in urinalysis?
Blood
What are we looking for an ECG?
A conduction delay caused by IE forming an abscess over part of the bundle of his or purkinje fibres.
Wide QRS
What shows up on a CXR in IE?
Heart Failure and Pulmonary Abscesses
What kind of ECHO do we use for Infective Endocarditis?
A Trans-Thoracic Echo (TTE) is 1st line
TOE is used if TTE is -ve but your still suspicious OR if TTE is +ve for a better view of abscess/vegetation/complications
What do we do if both TTE & TOE are -ve but were still suspicious of IE?
Repeat them 7-10 days later or earlier if theres a new complication
How many blood cultures do we take for IE?
3 from different sites with 6 hours between them.
Or if they’re in septic shock then just 2 from different sites with 1 hour between them.
Other than not having IE what else could cause -ve blood cultures?
Recent antibiotics
Fastidious Organisms have different diets so wont grow on blood culture (Nutritionally varied Strep - HACEK gram -ve bacilli - Brucella - Fungi)
Nor would Intracellular Bacteria (Coxiella Burnetii - Bartonella - Chlamydia)
What are the common complications of IE?
Heart Failure - Fistula Formation - Leaflet Perforation - Uncontrolled Infection - Abscess Formation - Atrioventricular Heart Block - Embolism - PVE & PV dysfunction
What criteria are needed to have a sure diagnosis of IE?
Either 2 Major, 1M & 3m or 5minor of the Modified Duke Criteria for a firm diagnosis
What are the Major Duke criteria?
- IE causing organisms in 2 seperate blood cultures
- IE organisms found in persistant blood cultures
- +ve blood culture for Coxiella Burnetii
- +ve ECHO
- New Murmur
What are the minor Duke Criteria?
- Predisposition (IVDA or Heart Condition)
- Fever
- Vascular Signs
- Immunologic Signs
- Microbiological evidence that doesnt meet the major duke critera (serology or blood culture)
What IE organisms show up in +ve blood culture?
Strep: Oral Viridans group - Miller/Aginosus Group - Bovis/Equinus complex (Group D Strep)
Staph: Aureus (Makes up most HCA IE) - Coagulase -ve stpah (CNS) epidermis
Enterococci - Faecalis/Faecium/Durans
How do we empirically treat IE? (I.e. before the blood cultures come back)
We use 2 IV antibiotics at once, AFTER the bloods are taken.
Standard is Gentamicin + Amoxicillin
What do we use to empirically treat IE if the patient is severely septic, allergic to penicillin or infected with MRSA?
Gentamicin + Vancomycin (replacing the amoxicillin)
What Antibiotic do we add if the patient has infected prosthetic valves?
Rifampicin
When do we use surgery as well as antibiotics?
The complications are indicators surgery is now necessary
How do we treat fungal IE?
With dual antifungals, often for life. And usually valve replacement too.
In what patients does Fungal IE occur?
In PVE/IVDA/immunocompromised patients.
FROM JANE?
Fever - Roth Spots - Oslers Nodes - Malaise - Janeway Spots - Anaemia - Nephritis (Nail haemorrhages) - Emboli
What are the vascular signs of IE?
Janeway Lesions
Splinter Haemorrhages
Vasculitis Rash
What are the immunological signs of IE?
Roth spots
Oslers Nodes
Nephritis
When is amoxicillin replaced with vancomicin in empirical IE treatment?
If the patient has severe sepsis, is allergic to penicillin or has MRSA
