Hydradenitis suppurativa and inflammatory bowel disease: An unusual, but existing association

Table 1 Case reports about the association Crohn’s disease-hydradenitis suppurativa

Ref.	n	Localization of CD	Localization of HS	CD predates HS
Ostlere et al[11], 1991	3	Colon	Anogenital	NR
Burrows et al[12], 1992	2	Colon	Anogenital, axillae, groin	NR
Gower-Rousseau et al[13], 1992	1	Ileo-colon	Perineum	NR
Attanoos et al[14], 1993	3	Colon, ileo-colon, colon-jejunum	Anogenital, axillae, perineum	Yes
Tsianos et al[15], 1995	1	Colon	Anogenital, axillae, sternum	Yes
Roy et al[16], 1997	1	Ileo-colon	Axillae	NR
Martínez et al[17], 2001	1	Ileo-colon	Axillae	Yes
Roussomoustakaki et al[18], 2003	1	Ileo-colon	Anogenital, axillae, groin	No
Yazdanyar et al[19], 2010	2	Colon	Axillae, groin, submammary	No
Goertz et al[20], 2008	1	Colon	Perianal	Yes
dos Santos et al[21], 2012	1	Rectum	Perianal	Yes
Hiraiwa et al[22], 2013	1	Ulcerative colitis	Groin	Yes

CD: Crohn’s disease; HS: Hydradenitis suppurativa.

Table 2 Main clinical and pathogenesis features of hydradenitis suppurativa and inflammatory bowel disease (adapted from van der Zee et al[23])

	CD	UC	HS
Localization	Entire alimentary tract	Colon	Inverse areas of the skin
Layer of inflammation	Transmural	Mucosa	Deep derm
Confluency of lesions	No (skip lesions)	Yes	Yes
Fistulae	Yes	No	Yes
Influence of smoking	Aggravates	No (or improvement)	Aggravates
Disease chronicity	Yes	Yes	Yes
Genetic predisposition	Yes	Yes	Yes
Influence of microbiota	Yes	Yes	Yes
Female predominance	↑	↑	↑↑
Response to anti-TNFα therapy	Yes	Yes	Yes

CD: Crohn’s disease; UC: Ulcerative colitis; HS: Hydradenitis suppurativa; TNFα: Tumor necrosis factor alpha.