A 22-year-old male develops dark brown macules and patches on his back following a severe acne breakout. These lesions are flat and correspond to the areas where acne lesions were previously present. This condition is best described as:

Explanation

Post-inflammatory hyperpigmentation (PIH) is a common acquired hypermelanosis that occurs after inflammation or injury to the skin. It presents as macules or patches of varying shades of brown or black, corresponding to the sites of previous inflammation (e.g., acne, eczema, trauma, burns). Vitiligo is depigmentation, melasma is typically symmetrical facial hyperpigmentation, and ochronosis involves bluish-black discoloration due to homogentisic acid deposition.