Antimicrobial Therapy: General Principles Flashcards
bactericidal Agent
kills bacteria
bacteria death
bacteriostatic agent
- inhibitory to growth of susceptible microorganisms
- holds bacteria till immune system kills it
Bactericidal or bacteriostatic agent, which one is probably not good to use for an immunodeficient patient?
Bacteriostatic
Why do you not want to use a broad spectrum of antibiotics on a patient?
bacteria is more likely to gain resistance
Resistant Microorganism
[drug] required to inhibit or kill concentration cannot be achieved safely
Synergy
Enhancement of action of one drug by another
Antagosims
Decreased action of one drug by another
Usually what two types of drugs put together will make an antagonism
bacteriostatic and bactericidal
How is bacteriostatic and bactericidal antagonisms bad
- static drug inhibits cell division and protein synthesis
- cidal drugs need the active cell division/protein synthesis to work
Post antibiotic effect
persistent effect of an antimicrobial on bacterial growth following brief exposure of organisms to a drug
name two examples that have high degree of post antibiotic effect
aminoglycosides
fluoroquinolones
Concentration Dependent Killing
bacterial killing is dependent on peak concentration
when does optimal killing occur for concentration dependent killing
Concentration exceeds 10 times MIC
what does MIC stand for
minimum inhibit component
Time dependent kill
- bacterial killing is dependent on amount of time the concentration stay above the MIC during dosing interval
- 40-50% above dosing interval
What happens when drug drops below the MIC level
bacteria develop resistance
Give two examples of antibiotics for concentration dependent killing
aminoglycosides
fluoroquinolones
In the cell membrane, what must antibiotics be able to pass in order to penetrate gram negative bacteria
pore
leukocytosis
increase white blood cell count
What are 4 ways the body confirms the presence of an infection
- Fever
- Leukocytosis
- physical findings
- predisposing factors
What are the 4 basic steps in therapy
- determine site of infection
- determine causative organism
- select drug
- follow up patient
Empiric therapy
culture site before starting antibiotics
Is it okay to start antibiotics based on only gram strain results
no
what are 2 reasons for starting antibiotics without knowing the causative organism
- site of infection is difficult to culture
2. serious infection
When is oral and IV routes of administration given?
oral: moderal infections
IV: severe infections
When is intramuscular given?
IV not obtainable
-short term
What disease has the hardest drug distrubution
meningitis
Many drugs are eliminated through what system
renal
define drug interactions
concurrent medication interferes with antibiotic
what is a disadvantage for combination therapy
added risk of toxicity
superinfection
infection occurring after or on top of an earlier infection, especially following treatment with broad-spectrum antibiotics
what are two examples of superinfection
C. diff
yeast infection
when someone spikes a fever what should you (doc) do
REPAN culture
check, urine, sputum, and blood
How do you take of abcess
drain it, don’t need antibiotic in most cases
what is a major symptom of C. diff
diarrhea
what does a superinfection do to normal flora
alterations in normal flora results in removal of inhibitory influences in the body
When patient starts antibiotics and has diarrhea what should you not give the patient? what can it cause
Immondium - only takes care of diarrhea not the toxin. toxic megacolon
gram positive oragnisms
staphylococcus
streptococcus
enterococcus
gram negative organisms what are the 3 catgegories
Piddly
Fence
Space
name the gram negative piddly bugs
Haemophilus morexella morganella shigella salmonella
name the gram negative fence bugs
proteus
eschericia coli
klebsiella
name the gram negative space bugs
serratia pseudomonas acinetobacter citrobacter enterobacter
what category of gram negative space bugs are the hardest to treat
SPACE
Name the atypical bugs
chlamydia
mycoplasma
legionella
name the anaerobe bugs
peptostreptococcus
bacteriodes
clostridium
common name for mycoplasma pneumonia
walking pneumonia
why is synergy a technique used for treating space bugs
- more likely to get correct sensitivity
- decrease chance of resistance
- Box in one Coverage
why is monotherapy a technique used for treating space bugs
- decreases chances of adverse drug reactions
- Ace in the Hole
anaphylaxis
an acute allergic reaction to an antigen to which the body has become hypersensitive.
what drug do you use as a last resort for space bug
colistin
what penicillins over space bugs
piperacillin
ticarcillin
what cephalosporins cover space bugs
ceftazidime
cefepime
what carbapenems cover space bugs
impinenem
meropenem
what monobactum covers space bugs
aztreonam
for box in one coverage what drugs are put together
a cell wall inhibitor with FQN or aminoglycosides
