Table 2.

AS prevalence studies in patients with IBD

Author and referencenumber	n	Origin of patients	Diagnostic criteria	Prevalence (%)
				AS	SpA	Sacroiliitis (Rx or MRI)	Inflammatory low back pain	Articular manifestations
de Vlam et al[53]	103	Referral center	ESSG	10	35	30	30	39
Scarpa et al[13]	79	Referral center	New York	25			18	43
Salvarani et al[17]	160	Open population	ESSG	2 (CD)	18.1			32.5
				5.1 (UC)
Palm et al[58]	654	Open population	ESSG	6 (CD)	22	2	19
				2.6 (UC)
				3.7 Total
Wordsworth et al[60]	42	Referral center	ESSG	25 (CD)		36

Rx: Radiography; MRI: Magnetic resonance image; ESSG: European Spondyloarthropathy Study Group.