Which bacterial infection is Cefepime unlikely to treat effectively?

Cefepime is a fourth-generation cephalosporin antibiotic that is particularly effective against a wide range of Gram-negative bacteria and is also used for certain Gram-positive infections. However, when it comes to Staphylococcus aureus, especially methicillin-resistant Staphylococcus aureus (MRSA), cefepime is not considered a first-line treatment option.

Staphylococcus aureus, particularly when resistant to methicillin, requires specific antibiotics such as vancomycin or linezolid, which target this organism more effectively due to its unique cell wall structure and mechanisms of resistance. Cefepime's spectrum of activity primarily focuses on more susceptible Gram-negative bacteria, and while it does cover some Gram-positive organisms, it does not have adequate efficacy against MRSA and similar resistant strains.

In contrast, cefepime is actually effective against urinary tract infections caused by susceptible bacteria, it is also indicated for certain gonorrhea cases, and it excels at treating a variety of Gram-negative infections, often serving as a choice for empiric therapy in febrile neutropenia and hospital-acquired pneumonia. Therefore, the limited effectiveness of cefepime against Staphylococcus aureus, particularly resistant strains, makes this the correct identification among the listed infections