Pathology · single question
Erysipelas is a superficial skin infection of the dermis and lymphatics. Which organism is responsible?
Show answer and explanation
Correct answer: A. Streptococcus pyogenes (Group A beta-hemolytic Streptococcus)
- A. Correct. Erysipelas is caused by Streptococcus pyogenes (Group A beta-hemolytic Streptococcus, GABHS). It presents as a well-demarcated, raised, bright red skin lesion with sharp borders (because it involves superficial lymphatics). It most commonly affects the face and lower legs.
- B. Staphylococcus aureus causes impetigo, folliculitis, and cellulitis — but erysipelas is specifically streptococcal.
- C. Streptococcus viridans causes infective endocarditis — not erysipelas.
- D. Pseudomonas causes wound infections, otitis externa, and nosocomial pneumonia — not erysipelas.