Introduction: This second part of the S2k guidelines is an update of the 2015 S1 European guidelines.Objective: These guidelines aim to provide an accepted decision aid for the selection, implementation and assessment of appropriate and sufficient therapy for patients with hidradenitis suppurativa/acne inversa (HS).Methods: The chapters have been selected after a Delphi procedure among the experts/authors. Certain passages have been adopted without changes from the previous version. Potential treatment complications are not included, being beyond the scope of these guidelines.Results: Since the S1 guidelines publication, validation of new therapeutic approaches has almost completely overhauled the knowledge in the field of HS treatment. Inflammatory nodules/abscesses/draining tunnels are the primary lesions, which enable the classification of the disease severity by new validated tools. In relation to the degree of detectable inflammation, HS is classified into the inflammatory and the predominantly non‐inflammatory forms. While the intensity of the inflammatory form can be subdivided by the IHS4 classification in mild, moderate and severe HS and is treated by medication accordingly, the decision on surgical treatment of the predominantly non‐inflammatory form is based on the Hurley stage of the affected localization. The effectiveness of oral tetracyclines as an alternative to the oral combination of clindamycin/rifampicin should be noted. The duration of systemic antibiotic therapy can be shortened by a 5‐day intravenous clindamycin treatment. Adalimumab, secukinumab and bimekizumab subcutaneous administration has been approved by the EMA for the treatment of moderate‐to‐severe HS. Various surgical procedures are available for the predominantly non‐inflammatory form of the disease. The combination of a medical therapy to reduce inflammation with a surgical procedure to remove irreversible tissue damage is currently considered a holistic therapeutic approach.Conclusions: Suitable therapeutic options while considering HS severity in the therapeutic algorithm according to standardized criteria are aimed at ensuring a proper therapy.

Background: Hidradenitis suppurativa (HS) is a chronic, inflammatory, debilitating skin disease characterized by painful deep lesions and associated with substantial disease burden.Objectives: The objective of this study was to describe physician‐ and patient‐reported clinical unmet needs from a real‐world perspective.Methods: This study used data from the Adelphi HS Disease Specific Programme, a point‐in‐time survey of dermatologists and their patients with HS in Europe and the United States. Dermatologists completed patient record forms (PRFs) for 5–7 consecutively consulting patients with HS; patients or carers of patients also optionally completed a patient/carer self‐completion questionnaire (PSC/CSC). Data collection included demographics, symptomatology and impact on quality of life (QoL).Results: Dermatologists (N = 312) completed PRFs for 1787 patients with HS; patient‐ and carer‐reported questionnaires (PSC/CSC) were completed for 33.1% (591/1787) of patients. The mean age was 34.4 ± 12.2 years and 57.6% of patients were female (1029/1787). Physician‐judged disease severity at sampling was categorized as mild in 66.0% (1179/1787), moderate in 29.3% (523/1787) and severe in 4.7% (85/1787) of patients. Deterioration or unstable condition over the previous 12 months was described by 17.1% [235/1372] and 12.6% [41/325] of physician‐ and patient/carer‐reported cases, respectively. Despite receiving treatment, high proportions of patients still experienced symptoms at sampling (general pain/discomfort [49.5%, 885/1787]; inflammation/redness of lesions/abscesses [46.1%, 823/1787] and itching [29.9%, 535/1787]); these symptoms were more frequent in patients with moderate or severe disease. Patients reported a mean Dermatology Life Quality Index score of 5.9 ± 5.4 (555/591; mild, 4.1 ± 4.3; moderate, 9.4 ± 5.4; severe, 13.3 ± 5.5) and a mean Hidradenitis Suppurativa Quality of Life score of 11.0 ± 10.6 (518/591; mild, 7.6 ± 8.3; moderate, 17.7 ± 10.0; severe, 31.0 ± 15.4) indicating a substantial impact on QoL.Conclusions: Patients with HS experienced a high disease burden despite being actively treated by a dermatologist. This study demonstrates that the burden of HS disease is generally poorly managed with a considerable impact observed on patients' QoL.