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by Fatima Ehsan
P a g e
Infective Endocarditis
ETIOLOGY
Streptococcus Viridans& Staphylococcus aureus
-
Staphylococcal endocarditis /normal heart
Streptococcous viridans / dental procedures
gp D enterococci /lower bowel& genitourinary m
Pseudomonas aeruginosa / intravenous drug users
Coagulase-negative staphylococci / indwelling central venous catheter
EPIDEMIOLOGY
congenital or rheumatic heart disease
Normal heart
rare in infancy
Vegetations at the site of the endocardial or intimal
In ≈30% of patients a predisposing factor is recognized
surgical or dental procedure in ≈65% of cases
Poor dental hygiene in children with cyanotic HD
Primary bacteremia with Staphylococcus aureus
CLINICAL MANIFESTATIONS
HISTORY
Prior congenital or rheumatic heart disease
Preceding dental, urinary tract, or intestinal procedure
IV drug use
Central venous catheter Prosthetic heart valve
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by Fatima Ehsan
P a g e
SYMPTOMS
Fever, Chills
Chest and abdominal pain
Arthralgia, myalgia, Malaise
Dyspnea
Night sweats, Weight loss
CNS manifestations (stroke, seizures, headache)
SIGNS
Fever, Tachycardia
Hemorrhages, osler nodes,CNSor
Embolic phenomena (Roth spots, petechiae, splinter
(
ocular lesions
Janeway lesions
Clubbing
New or changing murmur, Arrhythmias
Splenomegaly
Heart failure
Metastatic infection (arthritis, meningitis, mycotic arterial
Emboli)
aneurysm, pericarditis, abscesses, septic pulmonary
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by Fatima Ehsan
P a g e
LABORATORY
Positive blood culture (3-5 separate blood collections)
Elevated ESR, C-reactive protein
.
Anemia, Leukocytosis
Immune complexes
Hypergammaglobulinemia
Hypocomplementemia
Rheumatoid factor
Hematuria
Renal failure: azotemia, high creatinine
.
CXR: bilateral infiltrates, nodules, pleural effusions
.
Echo: valve vegetations, prosthetic valve dysfunction or leak myocardial abscess, new-
onset valve insufficiency
Diagnosis
The Duke criteria Major criteria include
:
(
positive blood cultures (two separate cultures for a usual pathogen
)
1-
2-evidence of endocarditis on echocardiography (intracardiac mass , regurgitant flow
near a prosthesis, abscess, partial dehiscence of prosthetic valves, or new valve
regurgitant flow).
Minor criteria include
predisposing conditions
fever
,
embolic-vascular signs.
Immune complex phenomena (glomerulonephritis, arthritis,
rheumatoid factor, Osler
nodes, Roth spots).
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by Fatima Ehsan
P a g e
a single positive blood culture or serologic evidence of infection.
echocardiographic signs not meeting the major criteria.
Two major criteria, one major and three minor, or five minor
criteria suggest definite endocarditis
TREATMENT
Antibiotic therapy immediately (a definitive diagnosis)
delays → endocardial damage and severe complications.
Empirical antibiotic : vancomycin(40mg/kg)+ Gentamicin
Total 4- 6 wks
high serum level& long period (avascular vegetations)
Ceftriaxon 100mg/kg or pencillin G 200,ooou/kg
bacteremia usually resolves in 24–48 hr
fever resolves in 5–6 days with appropriate antibiotic therapy
Resolution with staphylococcal disease takes longer
Heart failure:-anti failure measures
Surgical intervention
-
valve replacement : severe aortic or mitral valve involvement with intractable HF (Life
saving)
(
excise infected tissue (occasionally
Recombinant tissue plasminogen activation may help lyse intracardiac vegetations and
avoid surgery in some high-risk patients.
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by Fatima Ehsan
P a g e
PREVENTION
Antimicrobial prophylaxis, limited to greater risk for adverse outcome from SBE :
1-prosthetic heart valves, prosthetic
material
2-previous endocarditis
3-unrepaired cyanotic CHD
4-Completely repaired CHD(prosthetic material) 6m 5-Completely repaired CHD With
residual defect
-Proper general dental care and oral hygiene
-Vigorous treatment of sepsis and local infections
Amoxacillin oral 50mg/kg
Ampicillin injection 50mg/kg
Ceftriaxon 50mg/kg
Azithromycin 15mg/kg (allergy)