Which bacteria are 5th-generation cephalosporins most notable for covering?

Which bacteria are 5th-generation cephalosporins most notable for covering?

• A. MRSA
• B. Pseudomonas aeruginosa
• C. Enterococcus
• D. Escherichia coli

Answer: (A)

Fifth-generation cephalosporins stand out for their activity against MRSA because they effectively bind PBP2a, the altered penicillin-binding protein MRSA uses to resist other beta-lactams. This enables inhibition of cell wall synthesis in MRSA strains, which is not a characteristic of earlier cephalosporin generations. While these drugs have broad Gram-positive coverage and decent Gram-negative activity, they do not reliably cover Pseudomonas. So the notable target among the options is MRSA, rather than Pseudomonas, Enterococcus, or E. coli.

Fifth-generation cephalosporins stand out for their activity against MRSA because they effectively bind PBP2a, the altered penicillin-binding protein MRSA uses to resist other beta-lactams. This enables inhibition of cell wall synthesis in MRSA strains, which is not a characteristic of earlier cephalosporin generations. While these drugs have broad Gram-positive coverage and decent Gram-negative activity, they do not reliably cover Pseudomonas. So the notable target among the options is MRSA, rather than Pseudomonas, Enterococcus, or E. coli.