Perifolliculitis capitis abscedens et suffodiens is a chronic inflammatory disease of the scalp characterized by the presence of large and small nodules that suppurate and intercommunicate by sinus formation. It may be more frequent in black males than in others (summary by McMullan and Zeligman, 1956).

Acne inversa is a chronic inflammatory disease of the hair follicles whose characteristic features include draining sinuses, painful skin abscesses, and disfiguring scars. Manifestations typically appear after puberty. Familial acne inversa is genetically heterogeneous (summary by Wang et al., 2010). Some patients with PSENEN-associated acne inversa also exhibit reticulate hyperpigmentation consistent with Dowling-Degos disease (DDD; see 179850) (Zhou et al., 2016). For a general phenotypic description and a discussion of genetic heterogeneity of acne inversa, see 142690.

Acne inversa, also known as hidradenitis suppurativa, is a chronic inflammatory disease of the hair follicles whose characteristic features include draining sinuses, painful skin abscesses, and disfiguring scars. Manifestations typically appear after puberty. Familial acne inversa is genetically heterogeneous (summary by Wang et al., 2010). For a general phenotypic description and a discussion of genetic heterogeneity of familial acne inversa, see 142690.