Importance: Hidradenitis suppurativa (HS) is relatively common, with the prevalence of 0.05% to 4.10%, yet many patients receive inadequate treatment.

Objective: To review the diagnosis, epidemiology, and treatment of HS with an emphasis on advances in the last 5 years.

Evidence Review: A literature search was conducted using PubMed, MEDLINE (Medical Subject Headings [MeSH]), and EMBASE to include recently published treatment studies (searched from September 1, 2011, to May 1, 2017). Reviews, guidelines, conference abstracts, and studies with less than 10 patients were excluded. Furthermore, internet searches for guidelines on hidradenitis suppurativa using Baidu, Bing, Google, and Qwant browsers were performed.

Findings: The diagnosis of HS is made by lesion morphology (nodules, abscesses, tunnels, and scars), location (axillae, inframammary folds, groin, perigenital, or perineal), and lesion progression (2 recurrences within 6 months or chronic or persistent lesions for ≥3 months). HS is more common than was previously thought based on epidemiological analysis (0.05%-4.10%). Disability from HS can be significant. Patients with HS may have significant comorbidities (eg, obesity, metabolic syndrome, diabetes, and arthritis) and increased all-cause mortality (incidence rate ratio, 1.35 [95% CI, 1.15-1.59]). Antibiotic treatment with combinations of clindamycin and rifampicin, or ertapenem followed by combination rifampicin, moxifloxacin, and metronidazole for 6 months is effective. Adalimumab is effective in a significant proportion of patients and treatment with IL-1 and IL-12 receptor subunit beta 1 (Rb1) antibodies may also be useful. Tissue-sparing surgical techniques and carbon dioxide laser treatments also are available, but the evidence on clinical outcomes with these approaches is limited.

Conclusions and Relevance: Hidradenitis suppurativa is more common than previously thought and may be treated by an array of pharmacological and surgical techniques. Hidradenitis suppurativa should be considered in the differential diagnosis of nodular lesions or sinus tracts present in the axillae, groin, perineal, and mammillary fold regions.