Background and aims: Infliximab (IFX) is a monoclonal antibody used to treat patients with Crohn's disease (CD). Intra-abdominal abscess formation is a major complication of CD with negative effects on patient prognosis. We have analyzed risk factors for abscess formation in CD patients treated with IFX.
Methods: CD patients who received IFX between January 2000 and April 2011 at Keio University Hospital were analyzed retrospectively. Risk factors for abscess formation were assessed by univariate and multivariate logistic regression analyses.
Results: Intra-abdominal abscess was seen in 15 of 258 patients. Univariate analyses showed serum C-reactive protein (CRP) concentration at 14 weeks after initiation of IFX (p = 0.021), serum albumin concentration at week 0 (p = 0.022) and week 14 (p = 0.004), the presence of anal lesions (p = 0.036), progression of intestine deformation (p = 0.015) and early loss of response to IFX (p < 0.0001) to be risk factors. Multivariate analysis showed that CRP concentration at 14 weeks [odds ratio (OR) 1.361] and loss of IFX response within 6 months (OR 5.361) were independent risk factors.
Conclusions: Abscess formation should be suspected in patients with symptoms of CD recurrence during IFX therapy. Uncontrolled CRP concentration and early loss of response to IFX are risk factors.