This study will build on data from mice and humans implicating TRPV1 nociceptors in the pathogenesis of the type-17 chronic inflammatory skin disease Hidradenitis Suppurativa (HS). In this study, the investigators will test the hypothesis that inhibiting neuropeptide activity with botulinum toxin reduces pathogenic inflammation.

Botulinum toxin prevents vesicle fusion at nerve terminals thereby inhibiting neuropeptide release. The investigators will collect punch biopsies of lesional skin from HS patients before, and 1-2 months after botulinum toxin treatment (50U per axilla in 10 injections of 0.1mL) then perform flow cytometric, transcriptomic, and microscopic analysis of skin to determine if nonselective inhibition of neuropeptide release diminishes IL-17 driven skin inflammation.

Inclusion:

• Adults between ages 18 and 75 years with established diagnosis of hidradenitis suppurativa (HS)
• HS skin lesions of duration at least 1 year, HS skin lesions in at least two different body areas

Exclusion:

• Age < 18 years or > 75 years
• pregnant or breastfeeding
• neuromuscular disorder (ex. ALS, myasthenia gravis, Lambert-Eaton syndrome, myopathy)
• medical co-morbidity that is a relative contraindication to skin biopsy procedure (ex. end stage congestive heart failure or coagulopathy)
• active bacterial, fungal, or viral infection in the treatment area
• known hypersensitivity to botulinum toxin A preparations or any of their components (human albumin, saline, lactose, sodium succinate)
• prisoners
• adults unable to consent for themselves.

The study population will consist of men or women between the ages of 18-75 who have an established diagnosis of Hidradenitis Suppurativa who will undergo botulinum toxin treatment as part of routine care.

Research team will share data and samples from this study with other investigators who are interested in skin diseases, but in that case no patient identifying information will be shared.

for up to 7 years following data collection

Proposals should be directed to sarah.whitley@umassmed.edu.To gain access to data, requesters will have to sign a data access agreement.