CVS infection Flashcards
ENDOCARDITIS - BACKGROUND
“Infection of the — surface of the heart”
* Uncommon: <0.1% of hospital admissions
* Important:
–significant complications + potentially — ;
– — missed; need a high index of —
* Risk factors vary:
– — important in resource-poor countries;
– — often the risk factor in well-resourced countries
* Clinical microbiology role in – & —
* Preventable in some instances with –
endocardial
fatal
easily
ssupecison
Rheumatic fever
iv device
diagnosis and treatment
prophylactic antibiotics
CATEGORIES OF INFECTIVE ENDOCARDITIS:
* — valve endocarditis
* — valve endocarditis:
–> No — contact
–> — endocarditis
–> Healthcare-related endocarditis resulting from — procedures
Endocarditis in persons who inject drugs: often — sided ( — valve)
Other categorisation by
* Causative organism:
* — , — ,—, etc.
* Onset: “ —”, “—” - terms are rarely used now
native
prosthetic
health care
nosocomial
invasive
right sided ( tricuspid valve)
Staphylococcal, streptococcal, fungal
subacute and acute
WHY IS THE INCIDENCE OF
ENDOCARDITIS INCREASING?
* Prosthetic valve —
* — use (persons who inject drugs)
* — rich countries: the mean age of patients with endocarditis has increased
–Why?
▪population has —
▪ —- has declined in incidence
BUT
▪increasing use of — and 00
surgery
IV drug
resource
aged
rheumatic fever
implantable cardiac devices
and heart valves
risk factors:
1- —
* Investigations of, or procedures
(e.g. surgery) involving, the
gastrointestinal, genitourinary or
upper respiratory tracts
* Indwelling devices (IV lines,
pacemakers)
* Dental, e.g. tooth extraction
* Tonsillectomy
Other:
* — use
* — exposure/—
Patient factors:
* Heart lesion
– Prosthetic valve
– Previous endocarditis
– Patent ductus arteriosus
– Aortic +/or mitral regurgitation
or stenosis
* Chronic diseases
– particularly dialysis patients
– chronic liver disease
– malignancy
* Advanced age
* — use
* Poorly controlled diabetes
* Immunocompromised state
(including HIV infection).
procedures
intravenous drug
animal / pet
Corticosteroid
PATHOGENESIS:
* Usually there is a defect/lesion causing — in blood flow resulting in – to the— surface with —/— aggregated on the surface
* — infection following — or other procedure (large numbers of bacteria in the — )
* Platelets/fibrin on the surface act as a — for bacteria
* Bacteria adhere to clot/aggregate & a — develops: layers of platelets/fibrin, bacteria,
platelets/fibrin/bacteria etc.
*—, — & — complications follow
turbulence
damage
endocardial
platelets/fibrin
blood stream
dental
blood
nidys
vegetation
infective, immunological,embolic
summary:
so basically bloodstream infection + valve lesion+ platelets/fibrin lead to damaged endocardium which cause vegetation. this vegetation leafs to emboli as gangrene , tissue damage as valve rupture , Immune activation
vasculitis, acute glomerulonephritis , Bloodstream infection
fevers, rigors,
check slide12 for pic
AETIOLOGY - APPROXIMATE:
1- — (increasing) —
— 25%
— 15%
2- — (decreasing) —
‘viridans’ (oralis, mutans, mitis, bovis) 20-25%
enterococci 10%
other 5%
3-Others 4%
* Chlamydia, Q fever, brucella, legionella, mycoplasma, bartonella
(diagnosis using serology or PCR)
* — organisms - fastidious ~2%
require — incubation (grow slowly on culture plates)
* — 1-2%
No organism identified
stapglycocci
>40
s. aeurus
streptoccoci
<40
( so staph ad strep make up 80%)
HACEK
prolonged
fungi
clinical features , often non specific and needs high index of suspicion:
HISTORY
Non-specific symptoms: Malaise, fatigue, weight loss, arthralgia/ myalgia
EXAMINATION:
Fever: often — grade; chills, rigors, night sweats
Heart: new or changing —; +/- other cardiac signs
Abdomen: —
Immunological phenomena:
Hands + feet: — nodes (painful red raised lesions)
Eyes: – Spots (—-)
Unexplained embolic phenomenon:
Hands: —-
Arterial emboli (—), ‘stroke’, pulmonary infarcts (—)
low
murmur
splenomegaly
oslers node
roth spotrs ( retinal haemorrhages )
splinter haemorrhages
white leg
drug users
right sided endocarditis:
* Occurs in a —, — % of cases
* Associated with:
– Persons who —
– Cardiac —
– Central venous —
– — &— disease
* The —- is often affected
* There may be signs of — , — symptoms (—), — abscess(es)
* The outcome is generally good however there may be poor compliance amongst persons who inject —
minority
5-10%
inject drugs
device infections
venous catheters
HIV and congenital heart disease
tricuspid valve
sepsis , respiratory ( emboli) , lung
inject drugs
diagnosis of endocarditis:
1- — Ideally — sets taken before
starting – at least — apart
2- — (+other imaging)
transoesophageal (TOE) if available, superior to transthoracic (TTE)
3- Other investigations include serology (e.g. Q
fever), PCR, ESR/CRP (non-specific), urinalysis,
FBC
Culture/PCR of excised valves after —
The Modified Duke criteria are predictive of —
blood culture
3 sets
antibiotics
30 min
echocardiography
surgery
IE ( infective endocarditis)
modified duke criteria for infective endocarditis:
* Criteria are based on
– —
– — and
– — findings
– as well as the results of — and — results
* Criteria divided into – vs –
* Sensitivity of approximately —
* — diagnostic accuracy for early diagnosis
– especially in the case of — endocarditis (PVE) and — or — lead IE
* echocardiography is normal or inconclusive in up to 30% of cases
* Now 2023 ESC Modified Diagnostic Criteria
clinical
echocardiographic
biological findings
blood cultures and serology
major vs minor
80%
prosthetic valve , pacemaker , debrillator
classification :
1- definite: either 5 minor or 1 major +3 minor or 2 major
2- possible: 2 major + 1-2 minor or 3-4 minor
MANAGEMENT - 1
1. Unless the patient is very ill, confirm the — first before starting –
2. Liaise with clinical microbiology regarding diagnosis, optimal therapy & follow-up
3. Combination — therapy is usually required for — ; — courses are now increasingly being considered
4. Early consultation with a cardiac surgeon if complications (e.g. recurrent emboli) occur or if
there is failure to respond to treatment: up to 40%
require surgery
aetiology
antibiotics
antibiotic therapy
4-6 weeks
shorter
management -2:
What we can do for you:
* Confirm the —
–e.g. Str. mitis from repeat blood cultures – continuous
bloodstream infection
–Arrange other diagnostics – serology, PCR etc.
* — concentrations (MICs)
–i.e. how susceptible the organism is to —
* Advise on:
–the choice of —
–Regular — of aminoglycosides
(gentamicin) & glycopeptide (vancomycin) to
avoid/minimise the risk of toxicity
diagnosis
minimum inhibitory
choice of antibiotic
antibiotic assay
Suggested Empiric Treatment of Infective Endocarditis:
1- clinical condition:
Community Acquired
Native Valve
or
Late Prosthetic valve
(> 12 months post-surgery)
Early Prosthetic valve
(< 12 months post-surgery)
or
Hospital acquired
(Nosocomial)
2- likely organisms:
* Staphylococcus aureus
* Streptococcus species
* Enterococcus species
Those above plus
* Coagulase negative
staphylococci
* Resistant Gram-positive
organisms e.g. MRSA
3- empiric antimicrobial combonation:
Amoxicillin
Plus either
* Ceftriaxone
* Flucloxacillin & gentamicin
Vancomycin or Daptomycin
Plus Gentamicin +/-
Rifampicin
( Empirical treatment should be changed to targeted therapy once theorganism is identified within – )
24-48 hours
culture -ve endocarditis:
* Prior — treatment
* —- organisms:
– Nutritionally variant —
– — group
(Haemophilus species, Aggregatibacter species, Cardiobacterium
hominis, Eikenella corrodens and Kingella species)
* Uncommon – or — requirements
Examples Bartonella spp.
Chlamydia spp.
Coxiella burnetti (Q fever)
Brucella abortus
Legionella spp.
Tropheryma whipplei
Non-Candida fungi
antibiotic
fastidious
streptococci
HACEK group
bacteria or special growth
complications while on therapy:
* Worsening of —: valve rupture,
perforation, abscess, emboli
* Ineffective — – valve —
required
* — , e.g. Clostridioides difficile or
other infection, e.g. IV catheter infection
* Drug reaction may be mistaken for – to
respond
outmodes of IE:
Untreated:—% mortality
Treated: — % mortality (decreasing)
—% if prosthetic valve
Poor prognosis is associated with:
* elderly patients
* delay in treatment
* particular organisms
– Gram negative bacilli (e.g. E. coli)
– Fungal
– Q fever
* >1 valve involved
* valve destruction
* congestive cardiac failure
infection
antibiotic
valve replacement
superinfection
failure
100%
20%
40%
prevention of endocarditis:
1. Reduction of — :
– optimisation of the use and care of central venous
catheters, including use of aseptic techniques, early line removal, and avoidance of femoral access
2. Reduce rates of — :
– Treat — and — promptly
3. Improved — in at risk individuals
– Poor oral hygiene is associated with — after
tooth brushing
4. Patients undergoing cardiac—-
– — has been demonstrated to reduce
the risk of subsequent infection in this patient group
5. — in high-risk
individuals
– Next slides
bactereamia
rheumatic fever
Streptococcal pharyngitis and scarlet fever
dental hygiene
bacteraemia
cardiac device implantation
Antibiotic prophylaxis
Antibiotic prophylaxis
oral Antibiotic prophylaxis to reduce the incidence of bacterimia:
* Routinely practiced for many years in patients at risk of infective endocarditis undergoing an — (dental or other)
* The National Institute for Health and Clinical Excellence (NICE UK)
advised (in 2008) cessation of this practice
– absence of a strong evidence base, the overall risk of infective
endocarditis arising from dental procedures is — , indiscriminate antibiotic use is potentially hazardous
* In contrast, the European Society of Cardiology, the American
College of Cardiology, and the American Heart Association have
recommended ongoing use of antibiotic prophylaxis for patients at
highest risk
* New 2023 ESC guidelines advise prophylaxis in high-risk
individuals
invasive procedure
dental
low
prevention - antibiotic prophylaxis:
High Risk Groups
1. — infective endocarditis
2. prosthetic valve or prosthetic material used for cardiac –
3. — disease
4. Ventricular assist devices in –
Intermediate risk
1. — heart disease
2. – degenerative
valve disease
3. — abnormalities
including bicuspid aortic valve
disease
4. Cardiovascular —
5. —
Procedures:
Those that may cause bloodstream
infection/large inoculum of organisms
* Dental extractions or periodontal
surgery
* Instrumentation/surgery of URT,
GIT, GUT etc. usually when the
procedure is on an infected site
Which Antibiotics?
* — PO or IV ( — dose
before the procedure).
* Penicillin allergic = Cephalexin or
azithromycin or ceftriaxone
previous
repair
congenital heart
in sity
rheumatic
non-rheumatic
congenital valve
implanted electronic devices
hypertrophic cardiomyopathy
amoxicillin
single
pericarditis:
“Inflammation of the — , often with — ”
INFECTIOUS CAUSES:
* Viral: Coxsackie, influenza, adenovirus,
* Bacteria: Staphylococci/Streptococci, Chlamydia, TB (especially where
endemic)
CLINICAL FEATURES:
* May be preceded by “— “ or — symptoms if–causes.
* Signs and symptoms of — e.g., fever
* — pain: sharp and pleuritic, improved by — and leaning —
* Pericardial friction —
* ECG changes: New widespread ST — or PR —
pericardium
pericardial effusion
flu like
gastrointestinal symptoms
viral causes
systemic infection
fever
chest pain
sitting up and leaning forward
rub
ST elevation
PR depression
pericarditis:
DIAGNOSIS:
* — features
* —
* —
* Lab diagnosis:
– —
– — when indicated
TREATMENT:
* General measures
– — activity
* — +/- — or —
* Drainage of —
* — if bacterial pathogen
identified
clinical
ecg
radiology
serology
culture
restrict
NSAIDS
colchicine or steroids
pericardial effusion
antimicrobial
myocarditis:
“Inflammation of the — due to — , usually –”
INFECTIOUS CAUSES:
* Viral: Coxsackie, influenza
* Bacteria: Multiple gram positive and gram negative bacteria
Corynebacterium diphtheriae (unusual in the industrialised world)
* Parasites: Toxoplasma
CLINICAL FEATURES:
Suspect: — in cardiac biomarker(eg, troponin), ECG changes
particularly if the clinical findings are new and unexplained
* — pain
* New/worsening SOB at rest or exercise, and/or fatigue,
* Palpitation, and/or unexplained arrhythmia symptoms
heart muscle
infection
viral
rise
acute chest pain
myocarditis:
DIAGNOSIS:
* clinical features
* ECG
* radiology
* serology
TREATMENT
* Management of sequelae
– Heart failure, arrhythmias etc.
– Transplant, circulatory support
* Avoiding exacerbating activities
– Exercise, NSAIDs, alcohol
* — or — therapy not routinely used
* Antimicrobials if bacterial infection identified
sequelae
Antiviral or immunosuppressant
cardiac device infections:
* Cardiac devices: Pacemaker, implantable defibrillator
* Increasingly important as population ages
* 2% get infected in first 5 years
* INFECTIOUS CAUSES
– —- , e.g. S. epidermidis, S. aureus
* CLINICAL FEATURES:
– — with — & —
– — infection
– +/- —
* DIAGNOSIS:
– Clinical
– Blood cultures
– Culture of — or excised device
* TREATMENT:
– — control & — of — as for endocarditis
* PREVENTION:
– Surgical Site Infection prevention bundle
* Aseptic technique
* Antimicrobial prophylaxis
* Postop wound care
skin flora
local cellulitis
discharge & pain
bloodstream
endocarditis
pus
source control
weeks of antibiotic
vascular infections:
* Consider in the context of post-operative
infections
* presence of a — , e.g. aortic aneurysm
repair, renders diagnosis & treatment more
challenging
* Patients are often— with underlying — (e.g. ischaemic heart disease)or — diseases (e.g. diabetes mellitus
graft
cardiovascular
systemic
