Infective Endocarditis Flashcards
What are the goals of IE therapy?
1) Prompt diagnosis and administering the right anti-microbial therapy
2) Assessing the need to remove any infected implanted devices or atrioventricular shunts
3) Identify patients that need valvular surgery
4) Preventing recurrent infection of IE (by good dental hygiene, prophylaxis, and the closure of shunts if present)
What is an empiric treatment, and what is the empiric treatment for IE?
- Treating an infection or disease based on clinical judgment and experience, rather than waiting for specific diagnostic test results to confirm the exact cause of the illness.
- The empiric therapy should cover staphylococci (both MSSA & MRSA), streptococci, and enterococci, usually IV vancomycin is an appropriate choice
In the case of S.A IE which side of the heart (and valve) are most susceptible, and what is the main cause?
It is mainly due to drug abuse, and occurs in the right side of the heart, at the tricuspid valve
What is the clinical result that identifies the patient is responding to the initial empirical treatment?
1) You will see the fever and toxicity subside, while getting infected with a virulent organism like S.A might take 5-7 for the fibrillation to subside in other organisms it will usually take 3-5 days
To which patients should we prescribe antibiotic prophylaxis to prevent IE?
1) Patients with prosthetic materials
2) Patients with previous IE
3) Patients with cyanotic congenital heart disease
During which procedures should we prescribe prophylaxis for those patients?
1) Dental procedures
2) Procedures that are done to infected/diseased organ
When should we administer the prophylaxis?
A single dose regardless of it being IM, ORAL, or IV
- 30-60 minutes before the procedure
What is the appropriate prophylaxis for patients not allergic to penicillin/ampicillin
1) Amoxicillin (Oral, CI “Cell wall Inhibitor”)
2) Ampicillin (IM or IV, CI)
3) Cefalozolin “1st gen”/Ceftriaxone “3rd gen”(cephalosporin, given IM or IV, CI)
Which medication should we use as a prophylaxis for patients allergic to penicillin?
1) Cephalexin (oral)
2) Azithromycin or Clarithromycin (Macrolides inhibit the 50s ribosomal subunit inhibiting the protein synthesis, ORAL)
3) Doxycycline (Tetracyclin, inhibits the 30s ribosomal subunit, given ORAL)
4) Cefalozolin “1st gen”/Ceftriaxone “3rd gen”(cephalosporin, given IM or IV, CI)
Describe the perfect anti-microbial therapy for IE
1) The anti-biotic must be bactericidal and not static
2) The treatment must be prolonged (4-6 weeks)
3) Generally parenteral administration is preferable
4) Therapy regarding prosthetic valves that are implanted in less than 12 months (because after that it becomes part of the endocardium) and S.A infection IE are longer for about 2 weeks but the same antibiotic is used
- Successful treatment of IE relies on the complete eradication of the microbe, and if surgery is indicated it will only be to remove infected material
What is the proper empirical treatment for community-acquired IE in patients with a native valve or prosthetic valves for more than 12 months?
1) Ampicillin (IM or IV, CI)
2) Ceftriaxone “3rd gen”(cephalosporin, given IM or IV, CI) or (Flu)cloxacillin
3) Gentamicin (Aminoglycoside, Inhibits the 30S ribosomal subunit, IV or IM)
- Gentamicin should be used cautiously as it is highly nephrotoxic, but it is a good synergistic drug with ampicillin and the two others
What is the proper empirical treatment for IE in patients with a prosthetic valve for less than 12 months or health-care-related IE?
1) Vancomycin (Glycopeptide that inhibits cell wall synthesis via its inhibition for the synthesis of peptidoglycan, IV) or Daptomycin (acts on gram + bacteria decreasing the integrity of the cell wall, IV)
2) Gentamicin (Aminoglycoside, Inhibits the 30S ribosomal subunit, IV or IM)
3) Rifampin (Inhibits the synthesis of mRNA by inhibiting the RNA Polymerase enzyme, IV or ORAL)
What is the proper empirical therapy for patients with community-acquired NVE or late PVE, who are allergic to penicillin?
1) Cefazolin (1st generation cephalosporin, given IM or IV, CI) or Vancomycin (Glycopeptide that inhibits cell wall synthesis via its inhibition for the synthesis of peptidoglycan, IV)
2) Gentamicin (Aminoglycoside, Inhibits the 30S ribosomal subunit, IV or IM)
What is the importance of aminoglycosides?
They act synergistically with the cell wall inhibitors, useful for shortening the duration of the regimen, however, they are highly nephrotoxic
What is the proper antibiotic to use when treating IE caused by E.facealis
1) Ampicillin (IM or IV, CI)
2) Ceftriaxone “3rd gen”(cephalosporin, given IM or IV, CI)
- Aminoglycoside are contraindicated as enterococci can have resistant (High Level Aminoglycoside Resistance HLAR, like gentamicin)
What antibiotics should you use in case of strep IE that is sensitive to penicillin (MIC <0.125MG/l)?
1) Penicillin G
2) Amoxicillin (Oral, CI “Cell wall Inhibitor”) or Ceftriaxone “3rd gen”(cephalosporin, given IM or IV, CI)
- 4 weeks in NVE, and 6 weeks in PVE
Which antibiotic should you prescribe to patients with NVE who are allergic to penicillin?
Vancomycin or Daptomycin (acts on gram + bacteria decreasing the integrity of the cell wall, IV)
What is the clinical significance of adding GENTAMICIN to the antibacterial regimen?
It will shorten the duration of the treatment in the case of NVE from 4-week to 2-weeks, making the patient stay less in the hospital and thus less susceptible to virulent microorganisms
What should you prescribe to patients with NVE that are infected with strep strain that is resistant to penicillin?
1) Penicillin G (higher dosage, 4-weeks, IV, Inhibitis the cell wall synthesis by inhibiting the peptidoglycan cross-linking)
2) Amoxicillin (Oral, CI “Cell wall Inhibitor”) or Ceftriaxone (4-weeks)
3) Gentamicin (For 2-weeks, Aminoglycoside, Inhibits the 30S ribosomal subunit, IV or IM)
Which antibiotic you must administer for patients with staphylococci NVE infection that are MSSA?
1) (Flu)cloxacillin or Cefazolin (1st generation cephalosporin, given IM or IV, CI)
Which antibiotic you must administer for patients with staphylococci PVE infection that is MSSA?
6-Weeks:
1) (Flu)cloxacillin or Cefazolin (1st generation cephalosporin, given IM or IV, CI)
2) Rifampin (Inhibits the synthesis of mRNA by inhibiting the RNA Polymerase enzyme, IV or ORAL)
2-Weeks:
1) Gentamicin (Aminoglycoside, Inhibits the 30S ribosomal subunit, IV or IM)
Which antibiotic you must administer for patients with staphylococci NVE infection that are MRSA?
Vancomycin (Glycopeptide that inhibits cell wall synthesis via its inhibition for the synthesis of peptidoglycan, IV) for 4 weeks
Which antibiotic you must administer for patients with staphylococci PVE infection that are MRSA?
6-Weeks:
1) Vancomycin (Glycopeptide that inhibits cell wall synthesis via its inhibition for the synthesis of peptidoglycan, IV)
2) Rifampin (Inhibits the synthesis of mRNA by inhibiting the RNA Polymerase enzyme, IV or ORAL)
2-Weeks:
3) Gentamicin (Aminoglycoside, Inhibits the 30S ribosomal subunit, IV or IM)
Describe the therapy route for IE
1) First 10-Days:
- Inpatient treatment with IV
- Cardiac surgery if indicated
- Removal of infected cardiac devices
- Draining any abscess if present
2) After day 10-6th week:
- Perform transesophageal echo before therapy
- Complicated patient’s continuous inpatient IV treatment
- after 10 days post-treatment of 7 post-surgery consider administering Oral antibiotics for the patient
