Which organism is a Gram-positive cocci commonly implicated in hospital-acquired infections?

• A. Pseudomonas aeruginosa
• B. MRSA
• C. Escherichia coli
• D. Clostridioides difficile

Answer: (B)

Gram-positive cocci that are a major concern in hospitals are represented by MRSA. MRSA is a methicillin-resistant strain of Staphylococcus aureus, which appears as spherical cells in grape-like clusters on Gram stain. Its prominence in hospital-acquired infections comes from both its common presence in healthcare settings and its resistance to many beta-lactam antibiotics, making infections harder to treat. This fits the clue because the organism is a Gram-positive coccus and is a well-known culprit in HAIs. The other organisms listed do not match the shape and typical hospital role: Pseudomonas aeruginosa and Escherichia coli are Gram-negative rods, and Clostridioides difficile is a Gram-positive rod, not a cocci.