A brief ppt about IE

1. BY
AYYAPPA SARAVANAN VARSHINEE
GROUP 215
MICROBIOLOGY PRESENTATION
UNDER GUIDANCE OF
DR. JAI SHANKAR PILLAI

2.  INFECTIVE ENDOCARDITIS
 PATHOGNESIS
 SYMPTOMS
 ANTIBIOTIC REGIMENS FOR PROPHYLAXIS
 RISKS
 WHAT TO DO?
 ADVICE
 CONCLUSION
 FIND OUT MORE

3.  Infective endocarditis (IE) is a microbial infection of the heart valves or
the mural endocardium that leads to the formation of vegetations
composed of thrombotic debris and organisms, often associated with
the destruction of the underlying cardiac tissues.
 Although fungi and other classes of microorganisms can be responsible,
most infections are bacterial (bacterial endocarditis).
 Classification:
 Acute form
 Sub acute form

4.  Acute infective endocarditis is typically
caused by infection of a previously normal
heart valve by a highly virulent organisms
(e.g. Staphylococcus aureus) that rapidly
produces necrotizing and destructive
lesions. This infection is difficult to cure
alone with antibiotics and need surgery.
 In contrast Sub acute infective endocarditis
is characterized by organisms with lower
virulence (e.g. viridans Streptococci) that
causes insidious infections of deformed
valves with overall less destruction. Cure
can be achieved with antibiotics.

5.  A variety of cardiac and vascular abnormalities increase the risk of
developing IE. E.g. RHD with valvular scarring has historically been major
antecedent disorder.
 Endocarditis of native but previously damaged or abnormal valves is
caused most commonly by (50% to 60%) by Streptococcus viridans, a
normal component of oral bacterial flora.
 Staphylococcus aureus commonly found on skin can infect either healthy
or deformed valves and are responsible for 20% to 30% of cases; S.
aureus is a major offender in intravenous drug abusers.
 Other bacterial causes include enterococci HACEK group (Haemophilus,
Actinobacillus, Cardiobacterium, Eikenella and Kingella) which are
commensals in the oral cavity.

6.  Prosthetic valve endocarditis is caused most commonly by
coagulase-negative Staphylococcoi epidermidis.
 Other agents include gram-negative bacilli and fungi.
 Predisposing factors : seeding of micro organisms in blood
streams. The source may be from site of other infections
in different parts of the body, a dental or surgical
procedure, breaking of epithelial barriers of gut, oral
cavity or skin.
 In about 10% cases of endocarditis, no organism can be
isolated from blood ( “culture negative” endocarditis),
WHY?

7.  Due to stormy onset of acute endocarditis there will be rapidly developing
chills, fever, weakness and lassitude. Other clinical manifestations include
non specific fatigue, loss of weight and flu like syndrome.
 Murmurs are present in 90% patients with left sided IE.
 Other complications are Glomerulonephritis, Janeway lesions, Osler nodes
and Roth spots.
Erythromatous non tender lesions on palms and soles subcutaneous nodules in the pulp of digits Retinal hemorrhages in the eyes

8.  INVASIVE DENTAL PROCEDURES
 High risk dental procedures that are likely to cause high incidence of
bacteremia
 Tooth extraction
 Periodontal surgery, sub gingival scaling
 Replantation avulsed teeth
 Implant placement or apicoectomy
 Amoxicillin is a drug of choice for antibiotic prophylaxis against IE; oral
dosage of 2g before 30-60minutes before the procedure is recommended.
 Other drugs include Cephalexin, Cefazoline or Ceftriaxone, 1st or 2nd
generation oral Cephalosporin.
 In patients hypersensitive to penicillin are administered with Clindamycin
(600mg) orally or intravenously 60minutes before procedure.

9.  NON DENTAL NON CARDIAC INVASIVE PROCEDURES
 For respiratory tissue procedures that involve infected tissue,
patients are administered with anti-staphylococcal penicillin, oral
Cephalosporins such as Cephalexin or Cefazolin 30-60minutes
before the procedure. Clindamycin is also an alternative drug of
choice.
 Gastro intestinal and genitourinary procedures have higher risk
enterococci and gram negative bacilli (rarely cause IE). Amoxicillin
and Ampicillin are administered usually. Vancomycin for penicillin
sensitive patients.
 If infection involves skin or subcutaneous tissue, Vancomycin is
slowly injected one hour before the procedure for methicillin
resistant S. aureus or S. epidermidis.

10.  CARDIAC DEVICE IMPLANTATION INFECTION PROPHYLAXIS
 Device-related endocarditis is a part of the spectrum of the cardiac
implantable device infections and can occur in patients with other
cardiac abnormalities.
 S. aureus and coagulase negative Staphylococci are the prevalent micro
organisms associated with this case.
 1 gr of Cefazolin immediately before the procedure and another 1gr of
Cefazolin within 60minutes of device implantation significantly reduce
device related infections. Cefazolin is applicable only if methicillin
resistant is not widespread.
 Vancomycin is administered if methicillin resistant is a problem or
patient is colonized with methicillin resistant Staphylococci.

11.  Prophylactic antibiotics are associated with increase in antibiotic
resistance especially when administered repeatedly.
 The cost of administering an antibiotic to a single person is not
expensive but cumulative number of prescription in a community will
lead to economic burden.
 In the UK, NICE clinical guidelines no longer advise prophylaxis because
there is no clinical evidence that it reduces the incidence of IE and
there are negative effects (e.g. allergy and increased bacterial
resistance) of taking antibiotics that may outweigh the benefits.

12.  Identification of patient at high risk ( who is susceptible to above
mentioned risk factors). Relevant history should be elicited.
 So, if the patient shows positive for the risk factors he should be given
antibiotic cover or refer for a cardiologist assessment for antibiotic
prophylaxis.
 Antibiotics should be administered for the patients undergoing
procedures of respiratory, GI or urinary tissues only if the procedure
include the site of micro organism infected site or at high risk of IE.

13.  However 40% of IE shows normal heart and unsuspected defect. Hence
even most careful dental surgeon has the embarrassment of patient
developing IE with safe history.
 Patients with prosthetic heart valves, previous IE, CHD or RHD should
have planned preventive oral health care.
 The aim is to keep the periodontal infection at its lowest rate, to lessen
the severity of bacteremia by keeping the gingiva healthy.

14.  Offer people at risk clear and consistent information about prevention, including:
 the benefits and risks of antibiotic prophylaxis, and an explanation of why antibiotic
prophylaxis is no longer routinely recommended
the importance of maintaining good oral health
 symptoms that may indicate infective endocarditis and when to seek expert advice
the risks of undergoing invasive procedures, including non-medical procedures
such as body piercing and tattoos.


15.  It remains unclear that AP is effective against IE or
not.
 “ For those who believe, no proof is necessary; for
those who don’t believe, no proof is possible.”
 At present ESC guideline committee believes that AP
is effective for patients who are at high risk of IE.
 Providing prophylaxis procedures to patients at high
risk of adverse outcomes undergoing high risk
procedures seems to be efficient and cost effective.

16.  Robins and Cotran
Basics of Pathology (Vol 1) Pg. 559-562
 https://www.escardio.org/Journals/E-Journal-of-
Cardiology-Practice/Volume-16/vol16no33
 https://www.escardio.org/Journals/E-Journal-of-
Cardiology-Practice/Volume-16/Indications-for-
antibiotic-prophylaxis-to-prevent-infective-
endocarditis-in-adults