Digestive Diseases and Sciences (2018) 63:755–760
Risk Factors for Hidradenitis Suppurativa in Patients
with Inammatory Bowel Disease
Alexis J. Lukach
· Melissa I. Saul
· Laura K. Ferris
· Jason M. Swoger
Received: 12 October 2017 / Accepted: 7 January 2018 / Published online: 22 January 2018
© Springer Science+Business Media, LLC, part of Springer Nature 2018
Background Hidradenitis suppurativa (HS) is a chronic inﬂammatory skin disorder characterized by recurrent nodules,
abscesses, and sinus tracts that can be debilitating and signiﬁcantly impair quality of life. Small studies and case reports
have suggested a possible association between HS and inﬂammatory bowel disease (IBD).
Aims We performed a case–control study to further characterize IBD patients with HS in terms of smoking status, BMI,
sites aﬀected by HS, IBD type and features, and IBD medication history.
Methods A total of 38 patients with HS and IBD were identiﬁed and matched on age, gender, and IBD type to 136 controls
with IBD but not HS. Clinical characteristics of interest were obtained through extensive review of the electronic health
Results Among patients with HS and IBD, the most common sites aﬀected by HS were the inguinal, perianal, and axillary
regions. Relative to patients with IBD alone, patients with HS and IBD were nearly six times more likely to be current smok-
ers (p < 0.01) and nearly 11 times more likely to be obese (p < 0.01). Patients with HS and Crohn’s were signiﬁcantly more
likely to have ileocolonic and perianal disease than patients with CD only (OR 8.31, 95% CI 2.90–23.80 and OR 2.85, 95%
CI 1.19–6.81, respectively; p < 0.01 for both).
Conclusions Relative to patients with IBD who do not develop HS, patients with IBD and HS are more likely to be overweight
or obese, to be former or current smokers, and to have ileocolonic and/or perianal disease.
Keywords Hidradenitis suppurativa · Inﬂammatory bowel disease · Crohn’s disease · Ulcerative colitis
Hidradenitis suppurativa (HS) is a chronic inﬂammatory
skin disorder characterized by recurrent nodules, abscesses,
and sinus tracts . HS most commonly aﬀects the axillary,
inguinal, and anogenital regions . Because it is recurrent,
HS can be debilitating and signiﬁcantly impair quality of
life. The pathogenesis of HS is thought to be multifactorial,
with environmental and genetic mechanisms taking part.
Smoking, obesity, and both hormone and immune dysfunc-
tion are among the best-characterized risk factors for HS .
Studies have suggested that the chronic inﬂammation of
HS lesions can be partly attributed to dysregulated immune
responses around the pilosebaceous unit, as well as the bac-
terial environment of the skin . Accordingly, it has been
demonstrated that HS lesions have increased expression of
inﬂammatory cytokines IL-1β, IL-10, IL-17, and IL-12/23
[5–7]. There have also been reports of increased circulating
Electronic supplementary material The online version of this
article (http s://doi.org/10.1007 /s106 20-018-4919 -5) contains
supplementary material, which is available to authorized users.
* Jason M. Swoger
Alexis J. Lukach
Melissa I. Saul
Laura K. Ferris
University of Pittsburgh School of Medicine, 3550 Terrace
St, Pittsburgh, PA 15213, USA
Department of Medicine, University of Pittsburgh, 3471 Fifth
Ave, 1216 Kaufmann Building, Pittsburgh, PA 15213, USA
Department of Dermatology, University of Pittsburgh, 3601
Fifth Ave, 5th Floor, Pittsburgh, PA 15213, USA
PRA Health Sciences, 4130 Parklake Ave, Suite 400,
Raleigh, NC 27612, USA