1. Infective Endocarditis
Dr. Kalpana Malla
MBBS MD (Pediatrics)
Manipal Teaching Hospital
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2. Definition
• Infective Endocarditis (IE): an infection of the
heart’s endocardial surface
Classified into four groups:
– Native Valve IE
– Prosthetic Valve IE
– Intravenous drug abuse (IVDA) IE
– Nosocomial IE

3. Epidemiology
• The valves involved
– Mitral 28-45%
– Aortic 5-36%
– Both 0-35%
– Tricuspid 0-6%
– Pulmonary <1%

4. Epidemiology
• Incidence - varies according to location
• Males > females
• May occur at any age and increasingly
common in elderly
• Mortality 20-30%

5. Predisposing Factors
Iv drug use
Central line
Prosthetic valve
Previous IE
Murmur
Dental procedure
Rheumatic disease
Miscellaneous

6. Risk for Endocarditis
• High risk
– Prosthetic cardiac valve
– Prior episodes of endocarditis
– Complex congenital cardiac defect
– Surgical systemic-pulmonary shunts
– Intravenous drug abuse
– Intravascular catheters

7. Risk for Endocarditis
• Moderate risk
– PDA, VSD, primum ASD
– Co-Aorta
– Bicuspid aortic valve
– Hypertrophic cardiomyopathy
– Acquired valvular dysfunction
– MVP with mitral regurgitation

8. Risk for Endocarditis
• Low risk
– Isolated secundum atrial septal defect
– ASD, VSD, or PDA > 6 months past repair
– “Innocent” heart murmur by auscultation in the
pediatric population

9. Further Classification
• Acute • Subacute
– Affects normal heart – Often affects
valves damaged heart
– Rapidly destructive valves
– Metastatic foci – Indolent nature
– Commonly Staph. – If not treated, usually
– If not treated, usually fatal by one year
fatal within 6 weeks

10. • The terms acute and subacute are used to
define duration of infection, however are
older terms and should not be used
• A classification based on organism is
preferable

11. Pathophysiology
1. Turbulent blood flow disrupts the
endocardium making it “sticky”
2. Bacteremia delivers the organisms to the
endocardial surface
3. Adherence of the organisms to the
endocardial surface
4. Eventual invasion of the valvular leaflets

12. Infecting Organisms
• Common bacteria in children
– S viridans – 50% cases
– S. aureus – 40% cases
– S. fecalis ,Grp D sreptococcus (Enterococci)

13. Less common organisms
– P. aeruginosa, Staph epidemidis
– Histoplasma, candida, Aspergillus
– Coxiella burnetti, Brucella, chlamydia
– HACEK grp –
Hemophilus, Actinobacillus, Cardiobacterium
hominis, Eikenella, kingella

14. Symptoms
• Acute • Subacute
– High grade fever and – Low grade fever
chills
– Anorexia
– SOB
– Weight loss
– Arthralgias/ myalgias
– Fatigue
– Abdominal pain
– Arthralgias/ myalgias
– Pleuritic chest pain
– Abdominal pain
– Back pain

15. Signs
• Fever
• Heart murmur
• Nonspecific signs – petechiae, subungal or
“splinter”
hemorrhages, clubbing, splenomegaly, neurol
ogic changes
• More specific signs - Osler’s Nodes, Janeway
lesions, and Roth Spots

16. Petechiae
1. Nonspecific
2. Often located on extremities
or mucous membranes

17. Splinter Hemorrhages
1. Nonspecific
2. Nonblanching
3. Linear reddish-brown lesions found under the nail
bed
4. Usually do NOT extend the entire length of the nail

18. Osler’s Nodes
1. More specific
2. Painful and erythematous nodules
3. Located on pulp of fingers and toes
4. More common in subacute IE

19. Janeway Lesions
1. More specific
2. Erythematous, blanching macules
3. Nonpainful
4. Located on palms and soles

20. The Essential Blood Test
• Blood Cultures
– Minimum of three blood cultures
– Three separate venipuncture sites
– 5- 10mL in children
– ½ to 1hr apart
– Out of three one should be for anaerobic organisms
• Positive Result
– Typical organisms present in at least 2 separate samples
– Detects over 95% of cases

21. Negative blood culture
• Previous antibiotic
• Technical errors
• Unusual organisms- anaerobic
organisms,fungus

22. Additional supportive Labs
• CBC
• ESR and CRP
• Urinalysis-microscopic hematuria in 95%
• Immunologic tests –
• Increase in gamma globulins
• Presence of cryoglobulin
• Low Complement levels (C3, C4)
• RF- positive (59%)

23. Imaging
• Chest x-ray
– Look for multiple focal infiltrates and calcification
of heart valves
• EKG
– Rarely diagnostic
– Look for evidence of ischemia, conduction
delay, and arrhythmias
• Echocardiography- diagnostic tool for culture
negative cases

24. mitral valve vegetation

25. Making the Diagnosis
• Pelletier and Petersdorf criteria (1977)
• Von Reyn criteria (1981)
• Duke criteria (1994)
• Modified Duke Criteria

26. Diagnostic (Duke) Criteria
• Major criteria
– Positive blood culture for IE
– Evidence of endocardial involvement

27. Duke’s Major Criteria
• positive blood culture for IE
– typical microorganism (strep viridans, strep bovis, HACEK
group, staph aureus or enterococci in the absence of a
primary locus) for endocarditis from two separate blood
cultures
– persistently positive blood culture from:
• blood cultures drawn more than 12 hr apart, or
• all of 3 or a majority of 4 or more separate blood
cultures, with first and last drawn at least 1 hr apart

28. Duke’s Major Criteria
• Evidence of endocardial involvement
– positive echocardiogram for endocarditis

29. Duke’s Minor Criteria
• Predisposing heart condition or iv drug use
• Fever of 100.40F or higher
• Vascular phenomena :
- major arterial emboli
- septic pulmonary infarcts
- mycotic aneurysm
- intracranial hemorrhage
- conjunctive hemorrhages
- Janeway lesions

30. Duke’s Minor Criteria
• Immunologic phenomena:
- Glomerulonephritis
- Osler’s nodes
- Roth spots
- Rheumatoid factor)
• Microbiologic evidence:
- positive blood culture not meeting major
criteria or serologic evidence of active infection with
organism consistent with IE)
• Echocardiogram -consistent with IE but not
meeting major criteria)

31. Modified Duke Criteria
• Definite IE
– Microorganism (via culture or histology) in a
valvular vegetation, embolized vegetation, or
intracardiac abscess
– Histologic evidence of vegetation or intracardiac
abscess
• Possible IE
– 2 major
– 1 major and 3 minor
– 5 minor

32. Modified Duke Criteria
• Rejected IE
–Resolution of illness with four days or
less of antibiotics

33. Treatment
• Parenteral antibiotics
• Surgery
– Intracardiac complications
• Surveillance blood cultures

34. Antimicrobial Therapy
• Antibiotics IV for 2-6 weeks
1. Penicillin-susceptible streptococcal (PSSE) on native
cardiac valves:
• Penicillin G - 4 weeks or
• Penicillin G or ceftriaxone + gentamicin - 2 wks
2. Penicillin-resistant streptococcal (PRSE) on native
cardiac valves –
• Penicillin, ampicillin, or ceftriaxone for 4 weeks +
gentamicin for the first 2 weeks

35. Antimicrobial Therapy
3.PSSE on prosthetic valve-
• penicillin, ampicillin, or ceftriaxone - 6 wks +
gentamicin for the first 2 wks.
4. PRSE on prosthetic valve –
penicillin, ampicillin, or ceftriaxone for 6 weeks
+ gentamicin for first 2 wks

36. Antimicrobial Therapy
5. Enterococcal infection on native valves -
penicillin or ampicillin + gentamicin for 4-6
weeks

37. Antimicrobial Therapy
6.Methicillin-susceptible S aureus (MSSA) on
native valves :
- Nafcillin or oxacillin for at least 6 weeks +
gentamicin for 3-5 days is optional
7. Methicillin-resistant S aureus (MRSA) on
native valves:
- vancomycin for at least 6 weeks, with or
without 3-5 days of gentamicin

38. Antimicrobial Therapy
8. MSSA infection on prosthetic valve :
- Nafcillin or oxacillin + rifampin for at least 6
weeks, in combination with gentamicin for 2
weeks.
9. MRSA infection on prosthetic valve:
- Vancomycin + rifampin for at least 6 weeks, in
combination with gentamicin for 2 weeks

39. Antimicrobial Therapy
10. Gram negative endocarditis caused by
HACEK organisms: - ceftriaxone or ampicillin
plus gentamicin for 4 weeks

40. Culture Negative Endocarditis
• Intracellular organisms
– Bartonella henselae
– Coxiella burnetti
– Mycoplasma pneumonia
– Legionella pneumophila
• Diagnosis is made by checking IgM/IgG
serologies

41. Culture Negative Endocarditis
Treatment
• One should cover for the HACEK
organisms, alpha streptococci & last slide
• Ceftriaxone 2 grams IV daily + vancomycin 1 g
q 12 - 6 weeks

42. New Treatments
• Right-sided infective endocarditis due to methicillin-
susceptible S aureus (MSSA) in IV drug users
– 2-wk therapy with a penicillinase-resistant penicillin and
an aminoglycoside
– 2-wk monotherapy with IV cloxacillin
– short-term therapy is inappropriate if complicated by
ostomyelitis, meningitis, myocardial abscess, or
concomitant left-sided involvement

43. New Treatments
• Highly penicillin-susceptible Streptococcus viridans
or bovis
– Once-daily ceftriaxone for 4 wks
• cure rate > 98%
• easily administered as outpatient, avoid hospitalization, offers
significant cost savings
– Once-daily ceftriaxone 2 g for 2wks followed by oral
amoxicillin qid for 2 wks
– Once-daily ceftriazone and netilmicin for 2 wks

44. New Treatments
• Prosthetic valve endocarditis due to fluconazole-
susceptible Candida species
– many are due to bloodstream invasion
– chronic oral suppressive therapy with fluconazole for
inoperable disease

45. Surgical Treatment
• 15-25% of patients with IE are treated
surgically
• Indications -
– Antibiotic therapy fails
– Persistent vegetation after systemic
embolization
– Increase in vegetation size after antimicrobial
therapy
– Valvular dysfunction
– Fungal endocarditis

46. Complications of Endocarditis
• Cardiac 33-50%
• Neurologic 25-35%
• Emboli 15-35%
• Metastatic Abscesses <5%

47. Neurologic Complications
• Acute encephalopathy
• Meningitis
• Embolic stroke
• Cerebral hemorrhage
• Brain abscess

48. Embolic Phenomena
• Stroke
• Ischemic extremities
• Pulmonary emboli
• Paralysis due to embolic infarction of
either the brain or spinal cord
• Hypoxia from pulmonary emboli
• Abdominal pain (splenic or renal infarction

49. Metastatic Spread of Infection
• Metastatic abscess
– Kidneys, spleen, brain, soft tissues
• Meningitis and/or encephalitis
• Vertebral osteomyelitis
• Septic arthritis

50. Local Spread of Infection
• Heart failure
– Extensive valvular damage
• Paravalvular abscess (30-40%)
– Most common in aortic valve, IVDA, and S. aureus
– May extend into adjacent conduction tissue causing
arrythmias
– Higher rates of embolization and mortality
• Pericarditis
• Fistulous intracardiac connections

51. Septic Pulmonary Emboli

52. Poor Prognostic Factors
• Female • Diabetes mellitus
• S. aureus • Low serum albumen
• Vegetation size • Apache II score
• Aortic valve • Heart failure
• Prosthetic valve • Paravalvular abscess
• Older age • Embolic events

53. Thank you
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