P261. Infliximab trough levels in patients' developping cutaneous and rheumatologic paradoxical manifestations: A casecontrol study
D. Laharie1, J. Chapuis1, E. Chabrun1, V. Labat-Debelleix1, M. Capdepont1, V. De Ledinghen1, P. Blanco1
1Hôpital Haut-Lévêque, Service Gastroentérologie, Pessac, France
Background: Patients with an inflammatory bowel disease (IBD) treated with infliximab (IFX) may develop cutaneous or rheumatologic paradoxical manifestations (CPM and RPM, respectively) with time. Their pathogenesis remains unclear and may be associated with high IFX trough levels (ITL). The aim of our casecontrol study was to identify an association between ITL values and the occurrence of CPM or RPM.
Methods: From May 2010 to January 2011, IBD patients receiving maintenance with IFX were consecutively included in a monocenter cross-sectional study. At inclusion, defined by the first IFX infusion as maintenance during the study period, patients were screened for CPM and RPM. Diagnosis of paradoxical manifestation was assessed by the occurrence of typical clinical lesions and/or symptoms in patients without any cutaneous lesions or rheumatism before starting IFX, secondary confirmed by a dermatologist or rheumatologist. ITL, anti-IFX antibodies (ATI) (LISA-TRAKER®, Biomedical Diagnostics BMD) and antinuclear antibodies (ANA) were measured at baseline. ITL values were compared between patients with CPM or RPM and the others. Predictive factors for CPM and RPM were assessed in a multivariate analysis.
Results: One-hundred-twenty-one patients (69 W; median age: 27.4 years) have been recruited during the study period. Nine (7%), including 7 women, have developed a CPM (8 cases of psoriasis), and 10 (8%), including 7 women, a RPM (all with severe and disabling polyarthralgia). Median ITL were 5.87 (range: 0.5219.53) µg/mL in patients with CPM and 5.12 (0.0049.12) µg/mL in those without (P = 0.560), and 1.9 (0.0013.5) µg/mL in patients with RPM and 5.57 (0.0049.12) µg/mL in those without (P = 0.058). ATI have been detected in 16 (13%) patients, including 3 with RPM (P = 0.128) and none with CPM (P = 0.605). In multivariate analysis, no predictive factor associated with CPM could be identified and, the sole factor associated with RPM was anti-nuclear antibodies >1/100 at inclusion.
Conclusions: ITL and ATI levels were similar in patients developing IFX paradoxical manifestations. As suggested by elevated antinuclear antibodies, RPM could be related to an autoimmune disorder induced by IFX.