When it occurs with acne conglobata, hidradenitis suppurativa, and pilonidal cysts, the syndrome is referred to as the follicular occlusion triad or tetrad.
2.
In 1956 Pillsbury postulated follicular occlusion as the cause of acne inversa, which they grouped together with acne conglobata and perifolliculitis capitis abscendens et suffodiens ( dissecting cellulitis of the scalp ) as the " acne triad ".