Question

Staphylococcus aureus strains referred to as HA-MRSA are sensitive to which of the following?

1) methicillin
2) penicillin
3) most cephalosporins
4) vancomycin
5) none of the above

Answer 1

HA-MRSA strains of Staphylococcus aureus are resistant to methicillin and most other ß-lactams but are typically sensitive to vancomycin.

Step-by-step explanation:

Staphylococcus aureus strains referred to as HA-MRSA are resistant to many commonly used antibiotics, including methicillin, penicillin, and most cephalosporins due to the acquisition of a new low-affinity PBP which imparts resistance to all available ß-lactams.

However, HA-MRSA strains are generally still sensitive to vancomycin, which is often used as a treatment option for these resistant strains. Therefore, out of the options provided, vancomycin is the correct answer.