Hurley severity for hidradenitis suppurativa (HS)
| Degree of involvement | Definition27 | Reported range of patients* affected131625 (%) |
|---|---|---|
| Grade I | Abscess formation, single or multiple, without sinus tracts and cicatrisation | 7–68 |
| Grade II | Recurrent abscesses with sinus tracts and cicatrisation; single or multiple widely separated lesions | 28–83 |
| Grade III | Diffuse or almost diffuse involvement, or multiple interconnected tracts and abscess across entire area | 4–22 |
*Populations: Canoui-Poitrine et al13 included 302 consecutive HS referrals in France; Sartorius et al16 included 251 consecutive referrals to a clinic with interest in HS in Sweden (115 with HS); and Matusiak et al25 included 54 Polish patients with HS who qualified for surgical intervention.