When reviewing Ms. Robertson's culture and sensitivity test results, the nurse learns that the bacteria causing Ms. Robertson's infection are sensitive to penicillin. The nurse interprets this result to mean:

A. Bacteriostatics are narrow spectrum drugs, and bactericidal drugs are broad spectrum:

This statement is incorrect. The spectrum of activity (narrow vs. broad) of an antibiotic refers to the range of bacterial species that it can target, not whether it is bacteriostatic or bactericidal.

B. Bacteriostatic drugs inhibit bacterial growth, and bactericidal drugs actually kill bacteria:

This statement is correct. Bacteriostatic drugs work by inhibiting the growth and reproduction of bacteria without directly killing them, whereas bactericidal drugs directly kill bacteria.

C. Bacteriostatics work by inhibiting protein synthesis, and bactericidal drugs work by inhibiting nucleic acid synthesis:

This statement is incorrect. Both bacteriostatic and bactericidal drugs can target various bacterial cellular processes, including protein synthesis, nucleic acid synthesis, cell wall synthesis, and others. The mechanism of action is not a definitive factor in distinguishing between bacteriostatic and bactericidal drugs.

D. Bacteriostatic drugs actually kill bacteria, and bactericidal drugs inhibit bacterial growth:

This statement is incorrect. It contradicts the established definitions of bacteriostatic and bactericidal drugs. Bacteriostatic drugs inhibit bacterial growth without killing the bacteria, while bactericidal drugs directly kill bacteria.

A. Kanamycin (Kantrex):

Kanamycin is an aminoglycoside antibiotic, but it is not commonly used as a first-line treatment for MRSA infections. Aminoglycosides are not typically preferred for treating MRSA because they are not as effective against these resistant bacteria compared to other agents like vancomycin.

B. Vancomycin:

Vancomycin is a glycopeptide antibiotic and is considered the drug of choice for the treatment of MRSA infections, including serious bloodstream infections, pneumonia, and skin and soft tissue infections. It works by inhibiting cell wall synthesis in bacteria, including MRSA.

C. Streptomycin:

Streptomycin is another aminoglycoside antibiotic, similar to kanamycin. Like kanamycin, streptomycin is not typically used as a first-line treatment for MRSA infections because it is less effective against resistant strains compared to other agents like vancomycin.

D. Penicillin:

Penicillin and other beta-lactam antibiotics are ineffective against MRSA because MRSA is resistant to these antibiotics, including methicillin. Therefore, penicillin would not be an appropriate choice for treating MRSA infections.