Perifolliculitis capitis abscedens et suffodiens also known as dissecting folliculitis manifests with perifollicular pustules, nodules, abscesses and sinuses that evolve into scarring alopecia. When it occurs with acne conglobata, hidradenitis suppurativa, and pilonidal cysts, the syndrome is referred to as the follicular occlusion triad or tetrad. Its course is chronic and relapsing, and treatment is often difficult. Medical therapies include isotretinoin, antibiotics, and prednisone.
Ref: Scheinfeld NS. A case of dissecting cellulitis and a review of the literature. Dermatol Online J. 2003 Feb;9(1):8.