What is the characteristic of Grade IV acne?

Grade IV acne is characterized by the presence of cystic formations, which are large, inflamed nodules that can occur deep within the skin. These cysts are often painful and can lead to significant scarring if not treated properly. In this grade of acne, there are typically numerous comedones (clogged hair follicles), papules, and pustules alongside these cystic lesions. The inflammation is more severe compared to lower grades of acne, which usually exhibit milder symptoms and fewer blemishes. Therefore, the presence of cystic acne along with various other types of lesions like comedones and pustules distinctly defines Grade IV acne.

The other options suggest milder forms of acne, such as minor breakouts or the presence of only closed comedones and occasional pustules, which do not capture the more severe and complex presentation found in Grade IV acne.