Pathology · single question
Impetigo, a superficial bacterial skin infection presenting with golden-crusted lesions around the mouth in children, is MOST commonly caused by:
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Correct answer: D. Staphylococcus aureus
- A. Streptococcus mutans is the primary caries-causing organism — not a cause of impetigo.
- B. Pseudomonas aeruginosa causes wound infections, otitis externa, and opportunistic infections — not impetigo.
- C. Clostridium difficile causes antibiotic-associated colitis — not skin infections.
- D. Correct. Impetigo is most commonly caused by Staphylococcus aureus, and less commonly by Streptococcus pyogenes (Group A beta-hemolytic Streptococcus). It presents with honey/golden-colored crusted lesions around the mouth and nose in children and is highly contagious by direct contact.