ANSWERS GRADED A+
✔✔The most common bacterial contaminant in blood products is:
a. GPC
b. GNRs
c. Anaerobes
d. CPRs - ✔✔(b)
Gram negative rods (E. coli)
✔✔The most common acquired hospital infection is:
a. Pneumonia
b. Blood stream infection
c. UTI
d. Colitis - ✔✔(c)
Often related to placement of urinary catheters. Best treatment of a UTI is removal of
the catheter.
✔✔The most common cause of bloodstream infection:
a. UTI
b. Pneumonia
c. Colitis
d. Central line sepsis - ✔✔(d)
Workup after a fever: blood, urine, and sputum cultures; CXR (rule out pulmonary
infiltrate); change all lines; check WBC count
✔✔Antibiotics can be subdivided into bacteriostatic and bacteriocidal antibiotics. Each
of the following antibiotics is considered bacteriostatic except:
a. Bactrim
b. Tetracycline
c. Erythromycin
d. Gentamicin
e. Chloramphenicol - ✔✔(d)
✔✔The mechanism of aminoglycoside resistance is:
a. Plasmids for β-lactamase
b. Changes in cell wall binding protein
,c. Decreased active transport due to modifying enzymes
d. Enhanced metabolism of the bacteria - ✔✔(c)
Resistance due to modifying enzymes leading to decreased active transport
✔✔The mechanism of penicillin resistance is:
a. Plasmids for β-lactamase
b. Changes in cell wall binding protein
c. Decreased active transport due to modifying enzymes
d. Enhanced metabolism of the bacteria - ✔✔(a)
✔✔The mechanism of vancomycin or methicillin resistance is:
a. Plasmids for β-lactamase
b. Changes in cell wall binding protein
c. Decreased active transport due to modifying enzymes
d. Enhanced metabolism of the bacteria - ✔✔(b)
Resistance develops from change in cell wall-binding sites
✔✔Appropriate vancomycin peak and trough values (µg/mL) are:
a. Peak 20-40, trough 5-10
b. Peak 5-10, trough <1
c. Peak 40-80, trough 20-40
d. Peak <1, trough 5-10 - ✔✔(a)
✔✔Appropriate gentamicin peak and trough values (µg/mL) are:
a. Peak 20-40, trough 5-10
b. Peak 5-10, trough <1
c. Peak 40-80, trough 20-40
d. Peak <1, trough 5-10 - ✔✔(b)
✔✔A patient on gentamicin has a peak level of 80 and a trough of <1. The most
appropriate management is:
a. Continue current dosing
b. Decease dose but maintain frequency
c. Decrease dose and decrease frequency
d. Maintain dose and decrease frequency - ✔✔(b)
If peak too high → ↓ amount of each dose
If trough too high → ↓ frequency of doses
, ✔✔The mechanism of action for fluoroquinolones is:
a. Inhibition of RNA polymerases
b. Inhibition of DNA gyrase
c. Inhibition of ribosomes
d. Production of oxygen radicals - ✔✔(b)
Bacteriocidal
✔✔The mechanism of action for metronidazole is:
a. Inhibition of RNA polymerases
b. Inhibition of DNA gyrase
c. Inhibition of ribosomes
d. Production of oxygen radicals - ✔✔(d)
Metronidazole produces oxygen radicals which break up DNA in bacteria. It is a
bacteriocidal agent.
✔✔A patient with an enterococcal blood stream infection is best treated by which of the
following antibiotics:
a. Cefazolin
b. Ceftriaxone
c. Bactrim
d. Ampicillin - ✔✔(d)
Ampicillin (± gentamicin) was specifically designed to treat enterococcus, although this
will not pick up VRE.
Vancomycin
Timentin/Zosyn
✔✔Sludging in the gallbladder and cholestatic jaundice is characteristic of which of the
following antibiotics:
a. Quinolones
b. Bactrim
c. Erythromycin
d. Ceftriaxone - ✔✔(d)
Sludging in the GB and cholestatic jaundice are complications of ceftriaxone
✔✔Erythema multiforme is most likely with which of the following antibiotics: