Intralesional Treatments in Hidradenitis Suppurativa: A Systematic Review.

Hidradenitis suppurativa (HS) is an inflammatory chronic disease with difficult management. In some scenarios, intralesional (IL) treatments could be useful. However, the scientific evidence available is limited and heterogeneous. We aimed to synthesize the available scientific evidence on IL treatments in HS. We conducted a systematic review in July 2021. The clinical databases reviewed included MEDLINE and Embase. All types of epidemiological studies and case series with at least 10 patients were included; reviews, guidelines, protocols, conference abstracts, case series with less than 10 patients, and case reports were excluded. Fifteen articles representing 599 patients and 1,032 lesions were included for review. Corticosteroid injections were the most reported treatment. They showed effectiveness for the treatment of acute inflammatory lesions and fistulas in terms of reduction of lesion counts, symptoms, and signs of inflammation and were safe in general terms. Light-based therapies were the other main treatment group, including photodynamic therapy and 1,064-nm diode laser. They were also effective, but more local and systemic adverse events were reported. Other treatments included botulinum toxin type B and punch-trocar-assisted cryoinsufflation (cryopunch). They were effective and safe, although were reported anecdotally. The main limitation of the systematic review was the general quality of the articles included. In conclusion, IL treatments such as corticosteroid injections and light-based therapies seem to be effective and safe for both acute inflammatory lesions and fistulas, although more prospective studies, with higher sample sizes and with standardized outcomes are needed to provide more scientific evidence on the subject.