Which organism is commonly associated with carbuncles?

• A. Streptococci
• B. Staphylococci
• C. Pseudomonas
• D. Escherichia

Answer: (B)

Carbuncles are deep skin infections that start in hair follicles and spread into surrounding tissue, and they are most commonly caused by Staphylococcus aureus, a bacterium that frequently colonizes the skin and nasal passages. Its ability to invade follicles and form pus-filled lesions leads to the clustered boils seen in a carbuncle. While streptococci can cause other skin infections like cellulitis, they’re not the typical cause of carbuncles. Pseudomonas tends to show up in infections from moist environments or burns, and Escherichia coli is usually linked to gastrointestinal or urinary infections, not skin boils. So the organism most commonly associated with carbuncles is Staphylococcus.