A client's urine culture has come back showing that the infecting ...

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A client's urine culture has come back showing that the infecting organism is resistant to ciprofloxacin (Cipro).
 
  The client is upset, saying that this medication has worked every other time. What explanation should the nurse give to the client concerning the development of resistance?
  1. There are a number of ways that an organism can become resistant to an antibacterial. Sometimes one of the enzymes involved in bacterial DNA replication mutates so that the medication is no longer effective.
  2. You must be infected with one of the new 'superbugs.' There aren't many antibacterials that will work against it.
  3. Don't worry; the doctor will give you levofloxacin (Levaquin) to take instead of ciprofloxacin (Cipro).
  4. There are a number of ways that an organism can become resistant to an antibacterial. It probably happened because you didn't take your medication correctly the last time you took it.

Question 2

The nurse explains to a student nurse the mechanism by which resistance to fluoroquinolones occurs. The nurse knows the student requires further education when the student states:
 
  1. Bacterial cell walls become less permeable to the fluoroquinolones.
  2. Mutations to DNA helicase alter its ability to bind with fluoroquinolones.
  3. Mutations to DNA gyrase alter its ability to bind with fluoroquinolones.
  4. Certain bacteria have developed resistance pumps that remove fluoroquinolones from the cell.

[jessicaduplan]

Answer to Question 1

Correct Answer: 1
Rationale 1: One of the ways that resistance occurs against fluoroquinolones is by a mutation to DNA gyrase, decreasing the effectiveness of the fluoroquinolone.
Rationale 2: There is nothing that indicates that this client is infected with an extremely resistant organism.
Rationale 3: Resistance to one fluoroquinolone usually confers resistance to other fluoroquinolones. Levofloxacin is also a fluoroquinolone.
Rationale 4: Although it is possible that improper use of a medication can increase the chance of resistance, it does not fully explain this resistance.
Global Rationale: One of the ways that resistance occurs against fluoroquinolones is by a mutation to DNA gyrase, decreasing the effectiveness of the fluoroquinolone. There is nothing that indicates that this client is infected with an extremely resistant organism. Resistance to one fluoroquinolone usually confers resistance to other fluoroquinolones. Levofloxacin is also a fluoroquinolone. Although it is possible that improper use of a medication can increase the chance of resistance, it does not fully explain this resistance.

Answer to Question 2

Correct Answer: 2
Rationale 1: A change in bacterial cell wall permeability, the development of resistance pumps, and mutations to DNA gyrase contribute to resistance to fluoroquinolones.
Rationale 2: Fluoroquinolones do not bind with the enzyme DNA helicase. They bind with DNA gyrase, so resistance will occur from mutations to DNA gyrase.
Rationale 3: A change in bacterial cell wall permeability, the development of resistance pumps, and mutations to DNA gyrase contribute to resistance to fluoroquinolones.
Rationale 4: A change in bacterial cell wall permeability, the development of resistance pumps, and mutations to DNA gyrase contribute to resistance to fluoroquinolones.
Global Rationale: Fluoroquinolones do not bind with the enzyme DNA helicase. They bind with DNA gyrase, so resistance will occur from mutations to DNA gyrase. A change in bacterial cell wall permeability, the development of resistance pumps, and mutations to DNA gyrase contribute to resistance to fluoroquinolones.

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Excellent

[amit]

Gracias!