Clinical use of antimicrobials Flashcards
Gram -ve vs +ve
Gram -ve
- Anti-pseudo Penicillins
- Aztreonam
- 2nd gen. Cephalosporins
Gram +ve
- Penicillin G/V
- Anti-Staph Penicillins
- 1st gen. Cephalosporins
- Vancomycin
- Daptomycin
- Bacitracin
- Streptogramins
Extended Spectrum
- Amoxicillin/Ampicillin
- 3rd & 4th gen. Cephalosporins
- Fosfomycin
- Carbapenems
- Macrolides
- Fluoroquinolones
- Tetracyclines
- Glycylcylines
- Rifampin
- Sulphonamides
- Trimethoprim
- Chloramphenicol
- Nitrofurantoin
- Metronidazole
Aerobic vs. Anaerobic
Aerobes
- Aztreonam
- Aminoglycosides
- Fluoroquinolones
Anaerobes
- Metro
Both
- Penicillin G/V
- Carbapenems
- Cephalosporins
- Tetracyclines
- Glycylcylines
- Chloramphenicol
- Clindamycin
Bacteriostatic vs Bactericidal
Bactericidal
- Aminoglycosides
- Beta-lactams
- Fluoroquinolones
- Metronidazole
- Vancomycin
- Streptogramins
Bacteriostatic
- Clindamycin
- Macrolides
- Sulfonamides
- Tetracyclines
- Trimethoprim
Antimicrobial Elimination
Renal: Aminoglycosides, most cephalosporins, fluoroquinolones, penicillins, sulfonamides, tetracyclines (doxycycline primarily via bile), TMP-SMX, vancomycin
Hepatic: Chloramphenicol, clindamycin, erythromycin, clarithromycin, nafcillin
Antimicrobial effects on fetus and neonate
- Aminoglycosides: Possible damage to the eighth cranial nerve of the fetus
- Tetracyclines, glycylcyclines: Tooth enamel dysplasia, inhibition of bone growth
- Sulfonamides: Kernicterus (displacement of bilirubin from serum albumin)
- CAT: Gray baby syndrome
- Fluoroquinolones: Tendon rupture/damage
- Nitrofurantoin: hemolytic anemia
Surgical antimicrobial prophylaxis
Cardiothoracic
- Routine: Cefazolin
- MRSA: Cefazolin + vancomycin
- Penicillin-allergic Pt: Vancomycin + aztreonam (routine & MRSA)
Colorectal
- Ampicillin/sulbactam
- Penicillin-allergic Pt: Ciprofloxacin + metronidazole or ciprofloxacin + clindamycin
General surgery
- Cefazolin
- Penicillin-allergic Pt: Vancomycin or clindamycin
Neuro
- Cefazolin
- Penicillin-allergic Pt: Vanco
Orthopedics
- Cefazolin
- Penicillin-allergic Pt: Vanco or clindamycin
Vascular Surg
- Cefazolin
- Penicillin-allergic Pt: Cefuroxime
Surgical debridgement of animal bites
- dog bite: IV ampicillin-sulbactam for Pasteurella multocida
Treatment of MDR infections
- **For life-threatening sepsis: 3rd gen cephalosporin (Cefepime) + vanco (empiric therapy for life‐threatening infections – IV, broad spectrum & effective against MDR bacteria) **
- Anti-staphylococcal penicillins: Beta-lactamase producing bacteria (Gram +ve)
- Carbapenems: Beta-lactamase producing bacteria (Gram +ve and -ve)
- Aztreonam: Beta-lactamase producing bacteria (Gram -ve)
- Vancomycin: MRSA, enterococci
- Daptocyin: MRSA, enterococci, VRE
- Tigecycline: MDR Gram +ve and some Gram –ve bacteria
- Streptogramins: MRSA, VRE
- Linezolid: MRSA, VRE
Drugs causing C. Diff Colitis
Frequently cause
- Clindamycin
- Ampicillin
- Amoxicillin
- Cephalosporins
- Fluoroquinolones
Occasionally cause
- Penicillin
- Erythromycin
- Trimethoprim
Rarely cause C.difficile
- Tetracycline
- Metronidazole
- Vancomycin
- Fidaxomicin
- Aminoglycosides
C. diff treatment
- Metronidazole
- Vancomycin
- Fidaxomicin
Bacterial meningitis (Adults)
Community
- Empiric therapy: Vancomycin + 3rd gen. cephalosporin
- Likely pathoges: S. pneumoniae, N. meningitidis, H. influenzae
- Directed therapy: Pen G or Ceftriaxone
Posttraumatic/surgical
- Empiric therapy: Vancomycin + 3rd gen. cephalosporin
- Likely pathogens: S. epidermidis, S. aureus, P. aeruginosa, S. pneumoniae
- Directed therapy: Vanco, Oxacillin, Ceftazidime + gentamicin, Peng G or ceftriaxone
Immunocompromised
- Empiric therapy: Vanco + 3rd gen cephalosporin
- Likely pathogens: Listeria, P. aeruginosa, S. pneumoniae
- Directed therapy: Ampicilin + gentamicin, Ceftazidime + gentamicin, VAnco + 3rd gen ceph
Bacterial meningitis (Adults) - Propylaxis
- Rifampin
- Ciprofloxacin
- Ceftriaxone
Community-Acquired Pneumonia
Outpatients
- Previously healthy and no use of antimicrobials within previous 3 months -> macrolide or doxy
- Presence of comorbidities; immunosuppressing conditions or use of immunosuppressing drugs; or use of antimicrobials within previous 3 months -> Resp. fluoroquinolone or Beta-lactam plus a macrolide
Inpatients
- Non-ICU: Resp. fluoroquinolone or Beta-lactam plus a macrolide
- ICU: Beta-lactam (or aztreonam) plus either azithromycin or a resp. fluoroquinolone
*
Severe Febrile NeutropeniaCefipime (broad spectrum IV drug
Cefipime (broad spectrum IV drug)
