Characteristic	Colonised patients (18)	Non-colonised patients (44)	p-value
Age, mean years ± SD (range)	57.3±12.5 (29–73)	45.7±11.3 (24–74)	0.002*
Male gender, no. (%)	8 (44.4)	26 (59.1)	0.441
Diagnosis rheumatoid arthritis, no. (%)	11 (61.1)	19 (43.2)	0.316
Diagnosis ankylosing spondylitis, no, (%)	5 (27.8)	20 (45.5)	0.316
Diagnosis psoriatic arthritis, no. (%)	2 (11.1)	5 (11.4)	0.999
Duration of infliximab treatment, weeks, median (range)	205 (38–283)	95 (2–192)	<0.001*
Corticosteroid use, no. (%)	8 (44.4)	6 (12.8)	0.007*
Corticosteroid dose, deflazacort mg/day, median (range)	6.75 (6.0–45.0)	6.0 (6.0–10.0)	0.999
Methotrexate use, no. (%)	16 (88.9)	26 (59.1)	0.048*
Methotrexate dose, mg/week, median (range)	8.75 (7.5–20.0)	7.5 (5.0–20.0)	0.270

^*p<0.05.