Infectious Endocarditis (IE) Prophylaxis
Circulation 2007;115:1-19.
Courtesy Barry Gleason November  2007

INTRO:
Primary reasons for revision of the IE Prophylaxis Guidelines last written in 1997:
1. IE is much more likely to result from frequent exposure to random bacteremias associated with daily activities than from bacteremia caused by a dental, GI, GU, or respiratory tract procedure.

2. Prophylaxis may prevent an exceedingly small number of cases of IE, if any, in individuals who undergo one of these procedures.

3. The risk of antibiotic-associated adverse events  exceeds the benefit, if any, from prophylactic antibiotic therapy.

4. Maintenance of optimal oral health and hygiene may reduce the incidence of bacteremia from daily activities and is more important than prophylactic antibiotics for a dental procedure to reduce the risk of IE.

 

Determining the Need for Prophylaxis & Treatment is a
Three-Step Process:

I.   Heart:
Is there increased risk for adverse outcome from  Infectious Endocarditis?
II.  Procedure: Does procedure carry significant risk for bacteremia with organisms known to cause IE?
III. Antibiotic: Best antibiotic regimen?

I. Heart: Patients At Risk

INCREASED RISK for Adverse Outcomes from IE (Prophylaxis recommended)
• Prosthetic cardiac valve (both tissue & mechanical)
• Previous infectious endocarditis (IE)
• Following categories of congenital heart disease (CHD):
  • Un-repaired cyanotic CHD, including palliative shunts and conduits
  • Completely repaired CHD with prosthetic material or device, whether placed by surgery or by catheter intervention, during the first 6 months after the procedure
  • Repaired CHD with residual defects at the site or adjacent to the site of a prosthetic patch or prosthetic device (which inhibit endothelialization)
  • Cardiac transplantation patients who develop cardiac valvulopathy

Antibiotic prophylaxis is no longer recommended for cardiac lesions other than those listed above.

Low Risk:  NO prophylaxis necessary
• Isolated secundum atrial septal defect
• Surgically repaired atrial septal defect, ventricular septal defect, or patent ductus arteriosus 
     (without residua beyond 6 months)
• Previous coronary artery bypass graft surgery
• Mitral Valve Prolapse with or without regurgitation*
• Physiologic, functional, or innocent heart murmurs
• Previous Kawasaki disease without valvar dysfunction
• Acquired valvular dysfunction (e.g. rheumatic heart disease)* 
• Cardiac pacemakers (intravascular and epicardial) and AICDs

*Changed from 1997 Guidelines


II. Procedures w/ Significant Risk of Bacteremia from organisms known to cause IE:

IE is caused primarily by the following organisms: 
  -strep viridans (a catch-all term for numerous strep species that normally colonize the mouth), 
  -staph aureus (skin or respiratory tract), and 
  -strep faecalis, or "enterococcus", in the GI, GU, and biliary tracts. 

Antibiotic prophylaxis should be provided only for those procedures for which bacteremia with one or more of these organisms has a reasonable chance of occurring. These are:

A. Oral/Dental
-dental procedures that involve manipulation of gingival tissue or the peri-apical region of teeth or perforation of oral mucosa

B. GI, GU, Respiratory, Other
-respiratory tract procedures that incise or biopsy mucosa in the presence of active infection only
-skin or soft tissue I&D for infection
-GI or GU tract procedures in the presence of known or suspected infection only


II.A. Oral/ Dental Procedures

Antibiotic Coverage Recommended for High Risk Patients (see above):
• Dental extractions
• Periodontal procedures
• Endodontic (root canal) instrumentation or surgery only beyond the apex
• Subgingival placement of antibiotic fibers or strips
• Initial placement of orthodontic bands but not brackets
• Intra-ligamentary local anesthetic injections (only in infected tissue)
• Prophylactic cleaning of teeth or implants where bleeding is anticipated
No Coverage Recommended for:
• Cardiac catheterization, including balloon angioplasty
• Implanted cardiac pacemakers, implanted defibrillators, and coronary stents
• Tympanostomy tube insertion
• Restorative dentistry (operative and prosthodontic)
  Local anesthetic injections 
• Intracanal endodontic treatment; post placement and buildup
• Placement of rubber dams
• Postoperative suture removal
• Placement of removable prosthodontic or orthodontic appliances
• Taking of oral impressions
• Fluoride treatments
• Taking of oral radiographs
• Orthodontic appliance adjustment
• Shedding of primary teeth

II.B. GI, GU, Respiratory Procedures

Antibiotic Coverage Recommended:
Respiratory tract: Only if infected tissue
• Tonsillectomy or adenoidectomy: if infection suspected
• Surgical operations that involve the respiratory mucosa: if infection suspected
  Rigid Bronchoscopy: if infection suspected

GI tract
 
• ERCP with biliary obstruction: if infection suspected
• Biliary tract surgery: if infection suspected
• Surgical operations that involve intestinal mucosa: if infection suspected
• 
No Coverage Recommended for:
• Endotracheal intubation
• Bronchoscopy with a flexible bronchoscope, with or without biopsy (unless tissue is infected)
• Transesophageal echocardiography
• Endoscopy with or without gastrointestinal biopsy
• Vaginal hysterectomy
• Vaginal delivery
• Cesarean section
• In uninfected tissue:

Urethral catheterization
Uterine dilatation and curettage
Therapeutic abortion
Sterilization procedures
Insertion or removal of intrauterine devices
Circumcision
Prostatectomy
Cystoscopy (unless infection suspected)


III. Antibiotic Regimens for Prophylaxis

An antibiotic for prophylaxis should be administered in a single dose 30-60 minutes before the procedure. If it is inadvertently not given before it may be given up to 2 hours after the procedure.

Dental Procedures

Route Drug Adults Children
Oral Amoxicillin 2 gm 50 mg/kg
Oral, allergic to penicillin /ampicillin cephalexin, or
clindamycin, or
azithromycin, or
clarithromycin
2 gm
600 mg
500 mg
500 mg
50 mg/kg
20 mg/kg
15 mg/kg
15 mg/kg
Unable to take Oral ampicillin, or
cefazolin, or
ceftriaxone
2 gm IV, IM
2 gm IV, IM
1 gm IV, IM
50 mg/kg IV, IM
50 mg/kg IV, IM
50 mg/kg IV, IM
Unable to take Oral,
Allergic to PCN
cefazolin, or
ceftriaxone, or
clindamycin
1 gm IV, IM
1 gm IV, IM
600 mg IV, IM
50 mg/kg IV, IM
50 mg/kg IV, IM
20 mg/kg IV, IM

Respiratory Tract Procedures in presence of active infection 
same as above unless infection with staff aureus is known or suspected. If so, use an antistaph penicillin (nafcillin, oxacillin) or cephalosporin (cephalexin,cefazolin), or vancomycin if unable to tolerate a beta-lactam.
Skin or Soft Tissue Infections
use an agent active against staph and strep, such as an antistaph penicillin or cephalosporin (see above). Use vancomycin or clindamycin if unable to tolerate a beta-lactam or if known or suspected to have infection caused by a MRSA.
Genitourinary/Gastrointestinal Procedures with known or suspected infection 

use an agent against enterococcus such as amoxicillin, ampicillin, penicillin, or piperacillin. If unable to tolerate a beta-lactam, then use vancomycin. If known or suspected to have a resistant strain of enterococcus, then consultation with an infectious disease expert is recommended.