Response to: Remission of hidradenitis suppurativa after bariatric surgery

To the Editor: We recently read with interest the article Remission of hidradenitis suppurativa after bariatric surgery by Gallagher et al.¹ Obesity is an established risk factor for hidradenitis suppurativa (HS), and we appreciate the authors' work on this relevant piece. Weight loss is thought to improve HS symptoms by decreasing friction, microbial colonization, and inflammation associated with obesity.² Patients often inquire about the association between HS and obesity and the possibility of disease abatement with weight loss. Bariatric surgery is effective in reducing body mass index,³ but negative consequences of bariatric surgery for HS also should be considered.

HS patients avidly use online forums to share disease experiences. In a previously published abstract from 2013, we investigated whether online users described HS improvement after bariatric surgery.⁴ A Google query of “hidradenitis+weight loss/gastric bypass/bariatric surgery” found 2 Yahoo! groups: a 3839-member HS group and a 77-member group specific for weight loss in HS, as well as postings in other skin and obesity forums. Of 35 posts from patients who wrote about HS disease severity after bariatric surgery, 69% described worsening symptoms caused by an increase in skin folds after weight loss, 26% reported improvement after excess skin removal, and 37% discussed obstacles related to insurance coverage for removal of excess skin. Additionally, a retrospective chart review of HS patients undergoing gastric bypass at our institution yielded 2 cases comparing HS severity before and after surgery. Both patients had stable or worsening disease after surgery.

Currently, there are 52 HS support groups on Facebook, the largest of which has 12,217 members. Adding to previously collected data, we searched all posts related to “gastric bypass” or “weight loss” on this group and found 39 discussions. Of these, 25 were relevant and included 56 comments specific to the effects of bariatric surgery on HS severity. Only 29% of posters reported improvement or remission. Many patients (39%) conveyed neither improvement nor worsening of HS symptoms but were satisfied with weight loss results. Finally, almost one-third of patients (32%) stated that their HS symptoms were notably worse than before bariatric surgery, with increased number of flares or exacerbation of previously existing inflammatory lesions. Most patients reported improvement for the first few months after surgery, which many attributed to dietary changes and the rapid weight loss experienced in the immediate postbariatric period,⁵ and then worsening of HS flares with normalization of diet.

Taken together, these anecdotal data suggest that when counseling HS patients about bariatric surgery, it is important to note that disease severity may recur after initial improvement. Also, a patient's insurance coverage of skin removal should be determined preoperatively. Persistent skin conditions resulting from the panniculus is a criteria for determining the medical necessity for panniculectomy.⁶ Limitations of this review include its retrospective nature and patient-reported severity. Long-term follow-up with verification of disease severity is needed to determine the effect of gastric bypass on the severity of HS, including the potential contributory effects of dietary adjustments and excess skin fold removal.