INFECTIVE ENDOCARDITIS Flashcards
(26 cards)
INFECTIVE ENDOCARDITIS
• Definition: __________ of the heart’s __________ surface.
• Incidence: Commoner in the (developed or underdeveloped?) countries.
• Age: more in __________, but the incidence
increasing in children with ______ or central
indwelling ______________.
Infection ; endocardial
developed ; adults,
CHD ; venous catheters.
Common aetiology of IE
• _________________ group - common after
_________________.
• _________________ – common in patients
with _________________ disease.
• _________________ - common following _________________ manipulation.
• Streptococcus viridans ; dental extraction.
• Staphylococcal Aureus ; no underlying heart disease.
• Enterococcus ; GIT or GUT manipulation.
Others organisms that can cause IE besides the common 3
– __________________
– Fungi
– Enteric gram negative bacilli
HACEK (Haemophilus species, Aggregatibacter
species, Cardiobacterium hominis, Eikenella
corrodens, and Kingella species)
Predisposing Factors to IE
•Congenital heart disease – especially __________ CHD.
•_______________ disease
•Prosthetic _______
•Previous episode of ________________
•Surgical systemic to pulmonary shunts and conduits
•Cardiac ______________
•Central ______________
•_______ manipulations
•IV drug use
Cyanotic ; Acquired valve
valve; bacterial endocarditis
transplantation; venous catheters
Dental
Pathogenesis of IE
• Step 1: Formation of ______________ (_________)
– _____________ from acquired or congenital heart disease traumatizes __________
– which serves as a place for _________ and _________ ___________
• Step 2: Pathogen seeds blood
– Occurs via ________ to a mucosal surface from such daily activities as teeth brushing or chewing, or invasive activities like dental, GI, or GU procedures
non-bacterial thrombotic embolus (vegetation)
Turbulent flow; endothelium
fibrin ; platelet ; deposition
trauma
Pathogenesis of IE
• Step 3: Pathogen adheres to _________________ or ______
– Gram-positive cocci (Staph, Strep) most common pathogens
– Gram-negative bacteria (HACEK organisms) and fungi (Candida, Aspergillus) can also adhere
• Step 4: Pathogen promotes _____ deposition
– Micro-organism stimulates more fibrin deposition on pre-existing aseptic vegetation
– Creates secluded area within which pathogen can proliferate
fibrin-laden endothelium ; device
fibrin
Consequences of IE
• _______ damage
• ___________
•_________-mediated
Valvular
Emboli
Immune
Consequences of IE
• Valvular damage: Pathogen destroys _______ - cause _________ and possibly even ___________
• Emboli: ________ emboli travel to ______,_______ (CVA, mycotic aneurysm), kidney(microscopic hematuria & nephritis), or __________ and cause local infection and ischemia/infarction
• Immune-mediated: Circulating immune
complexes can possibly mediate __________,_________
valves; regurgitation; heart failure
Septic; lung ; brain; extremities
glomerulonephritis ; vasculitis
Clinical Findings of IE
• The presentation generally is indolent, with prolonged ____________ and a variety of non-specific somatic complaints - fatigue, weakness, arthralgia, myalgias, headache, anorexia, weight loss, rigors, and diaphoresis.
• Occasionally, presentation may be fulminant – acutely ill, rapidly changing symptoms and high, spiking fevers requiring urgent intervention.
Cause is most likely Streptococcus
pneumoniae or S aureus.
low-grade fever
Clinical findings of IE
• Valvulitis may result in changing cardiac auscultatory findings or CCF.
• Classic signs –
–____ spots
– _________ lesions
– _________ nodes
– _________ hemorrhage
Other features – skin petechiae, Splenomegaly, ±Underlying heart defect, ± Carious teeth or periodontal or gingival disease, ±Finger clubbing.
Roth; janeway; osler; splinter
Clinical findings of IE
• Classic signs –
– Roth spots (_________ hemorrhages with a _________ center)
– Janeway lesions (________________ on fingers and soles)
– Osler nodes (_________ lesions on _________ and _________)
– splinter hemorrhage – are (common or rare?) in children
retinal hemorrhages with a pale center
non tender macules on fingers and soles
painful lesions on hands and feet
rare in children
Clinical Findings in neonates
• Non-specific.
•_______ from IE are common, resulting in foci of infection outside the heart (e.g., __________,__________,____________).
•_________ difficulties
•______________
• Tachycardia
•______-tension.
• New or changing ___________.
• Neurological signs and symptoms (e.g ____________ , hemiparesis, or apnea).
Septic emboli; osteomyelitis, meningitis, or pneumonia
Feeding; Respiratory distress; Hypo
heart murmur; seizures
Investigations in IE
• Blood m/c/s-
–____ blood cultures at ____ separate venipuncture sites within 1st ________. If child is very ill, take all the samples within ___________. Do initial gram stain to guide Rx.
– Take _____ more on day 2 if no growth.
• If child is not acutely ill and blood culture still negative, __________ for 48hrs and repeat culture.
3; 3; 24hours
1-2hours; 2
Stop antibiotics
Investigations in IE
• _______________.
• ______ –Normocytic normochromic anaemia, hemolytic anemia. Leukocytosis- <50%.
• ESR , C reactive protein –
• Urinalysis/microscopy- haematuria, proteinuria
• ___________ factor
Echocardiography
CBC
Rheumatoid
Diagnosis of IE
Diagnosis: Requires a high index of suspicion when evaluating infection in a child with an underlying risk factor.
– Definitive diagnosis: _________________
– Conclusive anatomic diagnosis:
Demonstration of ___________ on _________
Positive blood culture.
vegetation on 2D.
Modified Dukes Criteria- Major criteria
- ——————— for IE
- Evidence of endocardial involvement
A. Positive ____________
B. New ___________________
Positive Blood culture
echocardiogram
valvular regurgitation
Modified Dukes Criteria
Minor criteria
1._____________
2. _____________
3. _____________ phenomena
4. _____________ phenomena
5. _____________ evidence
1.Predisposition
2. Fever
3. Vascular phenomena
4. Immunologic phenomena
5. Microbiological evidence
Diagnosis of Infective Endocarditis: Definite
• Clinical criteria
– _________ criteria
– _________ and _________ criteria
– _________ criteria
• Pathologic criteria:
– Microorganism demonstrated by culture or histologic examination of vegetation,
emboli, intracardiac abscess; or Active endocardial lesions on pathology examination.
– TWO major criteria
– ONE major and TWO minor
criteria
– FIVE minor criteria
Diagnosis of Infective Endocarditis:
Possible
•_________ criterion and ______ criterion
• ________ criteria
Rejected
• Probable alternative diagnosis
• Resolution of symptoms __________ after initiation of antibiotic Rx.
• No definitive histological or
bacteriological confirmation at surgery or autopsy.
I major ; 1 minor ; 3 minor
4 days
COMPLICATIONS of IE
• ________
•________
•_________ embolism
• Other infections e.g. meningitis, brain abscess, arthritis, osteomyelitis, pneumonia, renal abscess
• ___________ obstruction.
CCF
CVA
Pulmonary; Valvular
Treatment of IE
• Treatment is for __________.
• Consult with Microbiologist
• General – IV ( _________ or __________ or ___________) + ____________.
• Final selection of antibiotics depends on the organism isolated and the antibiotic sensitivity test.
•____________ for anaemia
• Nutrition
• Surgical: ___________, ____________ and replacement.
4-6weeks
Penicillin or ceftriaxone or vancomycin
Genticin; Blood transfusion
Vegectomy ; valve excision
Treatment with linezolid appears to result in outcomes superior to those with ___________ against many types of infections caused by ________ and ___________.
vancomycin
MRSA and MSSA
Use of ___________ should be strongly considered instead of vancomycin in patients who are seriously ill.
linezolid
Another advantage of linezolid is that its _______________________________________ in patients with renal failure.
dose does not need to be adjusted
