How would you differentiate erythema from infection in a wound?

• A. Erythema is redness; infection includes swelling, warmth, foul discharge, and systemic symptoms.
• B. Erythema involves swelling and warmth; infection has redness only.
• C. Erythema is warmth with discharge; infection lacks systemic symptoms.
• D. Erythema includes foul discharge; infection only redness.

Answer: (A)

Redness is a normal sign of inflammation called erythema, but infection adds other warning signs. The best description is that erythema is redness, while infection includes not only redness but also swelling and warmth around the wound, foul or purulent discharge, and systemic symptoms such as fever or a general feeling of being unwell. This combination helps distinguish a simple inflammatory redness from an infected wound. The other statements mix these signs—for example, suggesting erythema involves swelling and warmth or that infection is just redness or lacks discharge—but those ideas don't fit how infection manifests, which is redness plus additional local and sometimes systemic clues.