Classifying Hidradenitis Suppurativa
Hidradenitis suppurativa is a chronic persistent or recurrent suppurative disease of unknown cause occurring in the apocrine follicles, usually affecting the groin and axillae and also other apocrine-bearing sites such as the breasts, perineum and buttocks. Follicular occlusion may lead to chronic relapsing inflammation, mucopurulent discharge and progressive scarring. Induration, ulceration and also sinus and fistula formation may occur.
Hidradenitis suppurativa can be divided into the following three clinical stages (Hurley's classification):
Stage I: abscess formation, single or multiple without sinus tracts and scarring.
Stage II: recurrent abscesses with sinus tracts and scarring; single or multiple widely separated lesions.
Stage III: diffuse or almost diffuse involvement or multiple interconnected tracts and abscesses.
Other scoring and staging systems exist which may be used to monitor interventions in clinical trials:
Physician Global Assessment (PGA) score.
Hidradenitis Suppurativa Severity Index (HSSI).
Collier F, Smith RC, Morton CA; Diagnosis and management of hidradenitis suppurativa. BMJ. 2013 Apr 23;346:f2121. doi: 10.1136/bmj.f2121.
Zouboulis CC, Desai N, Emtestam L, et al; European S1 guideline for the treatment of hidradenitis suppurativa/acne inversa. J Eur Acad Dermatol Venereol. 2015 Apr;29(4):619-44. doi: 10.1111/jdv.12966. Epub 2015 Jan 30.