Infection of the endocardium

1. Infective Endocarditis

2. 07/25/162

3. Sessional Objectives
07/25/163
At the end of this session the learner should be able to:
 Define the term ‘infective endocarditis’
 Identify the aetiology of infective endocarditis
 Describe the clinical manifestations of IE
 Describe the lab investigations of IE
 Describe the Duke Criteria for diagnosis of IE
 Design the pharmaceutical management of IE
 Design the prevention of IE for patients at risk

4. Sessional Outline
 Definition & descriptions of ‘infective
endocarditis’
 Aetiology of infective endocarditis
 Clinical features of IE
 Duke criteria for diagnosis of IE
 Management of IE
 Prevention of IE
07/25/164

5. Definition & Descriptions
07/25/165
IE is an infection of the endocardium
Has significant morbidity and mortality;
require prompt diagnosis and Rx
Commonly runs an insidious course and is
known as sub acute (bacterial) endocarditis
(SBE).

6. Aetiology and
Pathogenesis
07/25/166
Endocarditis is usually the consequence of two
factors.
 Abnormal cardiac endothelium
 The presence of the organism in the blood
stream.

7. 07/25/167
Abnormal cardiac endothelium
 Is usually due to valvular lesions e.g. rheumatic
heart disease OR Prosthetic valves and prosthetic
valvular material
 Lesions promote fibrin and platelets deposition
(forming thrombi)
 Organisms adhere and grow in the thrombi

8. 07/25/168
Organisms in blood (bacteraemia)
Organisms causing IE usually arise from the mouth or the skin.
Risk factors include:-
Poor oral hygiene and dental sepsis
Dental procedures
Cellulitis and soft tissue infections
Intravenous drug abuse (IVDA)
Medical procedures such as intravascular canulae especially
central cardiac surgery
Permanent pace makers

9. Organisms Implicated
07/25/169
Streptococci (50 – 75%) ; - haemolyticα
streptococci
e.g.Strep. mutans
strep. viridans
& strep.sanguis
Enterococci (20%) e.g E. faecalis

10. 07/25/1610
 Staphylococci e.g Staph. aureus (most cases)
& Staph epidermidis
 Fungi e.g. Candida albicans (rare),
Aspergillus and Histoplasma
 Strep. bovis(rare but seen in bowel
malignancy)

11. 07/25/1611
 Fastidious organisms e.g.
oCoxiella species
oChlamydia spp.
oBrucella spp
oBartonella spp.
oLegionella
 Others; SLE, malignancy

12. Pathology
07/25/1612
Infection of the native valves usually occurs
along the edges of the heart valves.
Mitral and aortic regurgitation are the most
common pre-disposing valve lesions.
Infection of prosthetic valves occurs on the
valve insertion ring

13. 07/25/1613
The bacteria clump together due to agglutinating
antibodies
Vegetation may be very large and may embolize
Virulent organisms may rapidly destroy the valve
cusp, producing ulceration and regurgitation

14. 07/25/1614
The extracardiac manifestations
result either from
embolization or
the deposition of immune
complexes

15. Clinical Features
07/25/1615
 Cardiac
 Heart murmur
 Cardiac failure
 General Systems
 Malaise
 Clubbing of the fingers and toes
 Arthralgia
 Splenomegally
 Pyrexia/rigors

16. 07/25/1616
 Skin Lesions
 Osler nodes –Hard, tender, subcutaneous
swelling on finger, palms, toes & soles

17. 07/25/1617
Splinter hemorrhages of finger nails or toe
nails

18. 07/25/1618
Petechieal hemorrhages

19. 07/25/1619
• Janeway lesions –
small,erythematous, non- tender
macules on the palmar or plantar
surfaces

20. 07/25/1620
 Eyes
- Roth spots (boat-shaped retinal
haemorrhages with pale centre)
- Conjunctival splinter haemorrhages

21. 07/25/1621
 Embolic phenomena-
 Emboli may cause abscesses in the relevant
organ, e.g. brain, heart, kidney, spleen, GI
tract.
 In right-sided endocarditis, pulmonary
abscesses/ infarction may occur
 Mycotic aneurysm (infected aneurysm)
 Stroke (rare)

22. 07/25/1622
Others
Weight loss
Fatigue
Myalgia
Severe septicaemic illnesses

23. 07/25/1623
Blood Tests
Blood Cultures
Take 3 sets at different times and from different sites at
peak fever.
85-90% are diagnosed from the first 2 sets;
10 % are culture negative
Investigations

24. 07/25/1624
Serology
• Done when blood cultures are negative and
there is high suspicion of endocarditis
• Help to diagnose fastidious organisms and
candida
• Negative results usually arise if patients had
received antibiotic therapy.

25. 07/25/1625
Full Haemogram
 Normocytic, normochromic anaemia
 Neutrophil leukocytosis
 ↑ CRP
 ↑ ESR
 Thrombocytopaenia

26. 07/25/1626
Liver biochemistry
↑ Serum ALP
d) U &E
e) Mg2+

27. 07/25/1627
Igs and complement testing
  Serum Ig Gs
  C3 complement
  Total complement

28. 07/25/1628
Urinalysis
oProteinuria
oMicroscopic haematuria.

29.  Echocardiography
 Allows vegetation to be seen but only if
>2mm
 Documents valvular dysfunction, aortic
root abscesses
 Document small vegetations and
prosthetic valves
07/25/1629

30. 07/25/1630
Electrocardiogram (ECG)
Prolonged P-R interval at regular intervals
Shows evidence of myocardial infarction
(emboli) or conduction defects.
Conduction defects suggest the possibility of
valve ring infection or myocardial abscesses

31. 07/25/1631
Chest X – Ray (CXR)
Cardiomegaly
CTR >0.5
May show evidence of heart failure, or
emboli in right sided endocarditis.

32. Duke Criteria for Definitive
Diagnosis of Endocarditis
07/25/1632
Definitive diagnosis is based on:
2 major criteria OR
1 major and ≥3 minor criteria OR
All 5 minor(if no major criterion met)

33. Major criteria
07/25/1633
Positive blood culture
Typical organism in 2 separate cultures or
Persistently +ve blood cultures, e.g. 3, >12h apart
Endocardium involvement:
+ve echo (vegetation, abscess, dehiscence of prosthetic
valves) or
New valvular regurgitation (change in murmur not
sufficient)

34. Minor criteria
07/25/1634
Predisposition (cardiac lesion, IVDA)
Fever > 38deg C
Vascular/immunological signs
Positive blood culture that do not meet major criteria
Positive ECHO that does not meet the major criteria

35. How to diagnose
07/25/1635
Definitive infective endocarditis:
2 major or 1 major and ≥3 minor criteria
or all 5 minor(if no major criterion is met)

36. Management of IE
07/25/1636
Microbiologist , Cardiologist &
Clinical Pharmacist needed
Empiric Drug Therapy
Usually bactericidal antibiotics are used
for 2-6 weeks.

37. 07/25/1637
Clinical situation Suggested Antibiotic
regimens to start
a) Clinical Endocarditis
no suspicion of
staphylococci.
b) Suspected
staphylococcal
c) Streptococcal
(Penicillin sensitive)
Penicillin 1.2g Q4H,
Gentamicin 80 mg Q12H
Vancomycin 1g Q12H
Gentamicin 80-120mg
Q8H
Penicillin 1.2 g Q4H
Gentamicin 80mg Q12H
Note:- All antibiotics given iv

38. 07/25/1638
Clinical situation Suggested Antibiotic regimens to
start
d) Enterococcal
e) Staphylococcal
Ampicillin/ Amoxicillin 2g Q4h
Gentamicin 80mg Q12H
Vancomycin 2g Q12H, OR
Flucloxacillin 2g Q4H,OR
Benzylpenicillin 1.2g Q4H PLUS
Gentamicin 80-120mg Q8H
* For penicillin allergy, use
Vancomycin 1g/12h IV
Note:- All antibiotics given
iv

39. 07/25/1639
Clinical situation Suggested Antibiotic regimens to start
f)Coxiella
g) Fungi
Doxycycline 100mg/12h PO indefinitely
+co-trimoxazole, rifampicin or
ciprofloxacin
Flucytosine 3g/6h IV followed by
fluconazole 50mg/24h PO (a higher dose
may be needed). Amphotericin B if
flucytosine resistance or Aspergillus.
Miconazole if renal function poor

40. Surgery
07/25/1640
Is considered if
- Extensive damage to valve
- Heart failure
- Valvular obstruction
- Repeated emboli
- Unstable infected prosthetic valve – valve
replacement is usually required.
- Persistent infection despite therapy.
- Myocardial abscess
- Large vegetations

41. Prognosis
07/25/1641
Overall mortality is about
30% with staphylococci;
14 % with bowel organisms;
6 % with sensitive streptococci

42. 07/25/1642
Prophylaxis and Prevention
Meticulous oral and skin hygiene.
Better care during insertion and handling of
intravascular catheters
Prompt removal of IV catheters if they
become infected.

43. Patients at Risk
07/25/1643
Prosthetic or homograft heart valves
patient
In patent ductus arteriosus
In ventricular septal defects
Previous endocarditis
Mitral prolapse or regurgitation
Acquired valve disease

44. 07/25/1644
Procedure Drugs
Dental /URT Procedure (under LA)
Dental (under GA)
GIT or OBS/GYN or dental (GA)
and Genitourinary
To prevent rheumatic fever
PO Amoxicillin 3g stat 1 hr before
or clindamycin 600mg stat 1 hr before
Or Chlorhexidine mouthwash
IV amoxycillin 1gm stat at induction,
then 500mg PO 6hr after procedure
IV Amoxicillin 1g stat and IV
gentamicin 120mg stat at induction IV.
Then PO Amoxycillin 500mg stat
(Vancomycin for penicillin allergic
patient) 6 hrs after procedure
Pen V 250mg BD or Sulfadiazine 1g
when Penicillin allergic.
Antimicrobal Prophylaxis in Patients at Risk

45. Long Term Management of
Patients
07/25/1645
Continued administration of oral pen V 250mg
OD
Benzathine Penicillin 916mg I/M monthly till
the patients is 20 years old or 5 years after the
latest attack.
Sulfadiazine can be used in penicillin allergy
cases

46. Have We Covered Our
Objectives?
07/25/1646
 Define the term ‘infective endocarditis’
 Identify the aetiology of infective endocarditis
 Describe the clinical manifestations of IE
 Describe the laboratory investigations of IE
 Describe the Duke Criteria for diagnosis of IE
 Design the pharmaceutical management of IE
 Design the prevention of IE for patients at risk