What grade of acne involves pustules?

The correct answer involves the recognition that Grade III acne is characterized by the presence of pustules. In this stage of acne, lesions are more severe and often include both papules and pustules, which are inflamed and filled with pus. This indicates a higher level of inflammation and bacterial activity compared to the lower grades of acne.

Grade I typically consists of only minor comedones (clogged pores), while Grade II presents with more comedones and some papules, but not pustules. Grade IV, on the other hand, is the most severe, often associated with nodular lesions and cysts, rather than pustules alone. Thus, Grade III is the stage where pustules become a significant feature, highlighting both the inflammatory process and the need for more aggressive treatment.