Principles Of Antimicrobial Therapy Flashcards
3 goals of treatment
- kill bacteria
- avoid resistance
- avoid toxicity
Major abx classifications based on MOA (5)
- inhibition of cell wall synthesis
- inhibition of protein synthesis
- inhibition of cell membrane funct.
- inhibition of nucleic acid synthesis
- interference w/ bacterial metabolism
What effects should abx have on hosts?
Typically should not affect host
3 criteria for drug classification
Structure, predicted spectrum, & action
Bacteriostatics are used for
Mild infections
Bacteriocidals are used for
Killing bacteria fast
5 categories of antimicrobial therapy
Prophylaxis, pre-emptive, empiric, definitive, suppressive
Prophylaxis
- assc w/ no infection
- give drug to prevent possible infection
- decrease in usage bc of resistance concerns
Pre-emptive
- assc w/ infection
- prevents spread of infection
Empiric therapy
- assc w/ symptoms
- highly practiced
- sometimes see resistance
Definitive therapy
- assc w/ pathogen isolation
- select best abx for tx
Suppressive therapy
- assc w/ resolution
W/o identifying causative organisms & their susceptibility patterns…
Serious diseases may be life threatening
5 Pathologies that don’t require abx use
- fever alone
- solely on leukocytosis evidence
- most cats w/ lower urinary tract symptoms
- diarrhea in K9 & cats
- pancreatitis in small animals (usually sterile)
Goals of abx drugs
- effective
- appropriate for disease
- minimal residues in food animals
Source of genitourinary tract infections
Gram -ve aerobes
Source of infection for abdominal infect.
Initially gram -ve aerobes
Then anaerobes
Sourcee of skin infections
Staphylococcus sp. (gram +ve)
Source of abscess infection
Anaerobes and pasteurella
Source of UTIs
- E. Coli (60-65%)
- Proteus mirabillis (15-20%)
Tier one drugs
- clear dx
- no risk of abx drug resistance
Tier two drugs
Mandatory abx susceptibility tests
Tier three drugs
- for highly resistant infections
- use strongly discouraged
- use w/ specialist consult
1st tier drugs (5)
- clindamycin
- lincosamide
- 1st gen cephalosporins
- amoxicillin-clavamox
- TMPS
