Background: Osteoporosis has received increasing attention as a potential complication of Crohn's disease. Among cytokines tumor necrosis factor-alpha plays a pivotal role in the pathogenesis of inflammatory bowel diseases by inducing a wide variety of inflammatory responses, including bone resorption. Only few data are present about the effect of infliximab on bone metabolism.
Aims: The authors evaluated the effect of infliximab on bone metabolism in patients with Crohn's disease.
Patients and methods: Twenty seven patients (17 females, 10 males, mean age 32.58 yrs) with refractory fistulizing Crohn's disease were treated with a series of three infusions of 5 mg infliximab per kg at weeks 0, 2, and 6. Biochemical markers of bone formation (osteocalcin) and bone resorption (beta-CrossLaps) were measured before administration of each infliximab infusion. 54 patients were studied with inactive Crohn's disease (Crohn's disease activity index < 150) as a control.
Results: There were significant differences in beta-CrossLaps concentrations (ng/ml) between the day 0 and 14 (0.57 +/- 0.32 vs. 0.46 +/- 0.29, p < 0.01) and the day 0 and 42 (0.57 +/- 0.32 vs. 0.45 +/- 0.26, p < 0.05). The osteocalcin levels significantly increased from day 0 to day 42 (21.31 +/- 12.14 vs. 25.64 +/- 16.97, p < 0.05). The serum beta-CrossLaps and osteocalcin levels were 0.47 +/- 0.24, 27.2 +/- 8.44 in the control group respectively. These results differed from the serum levels of active patients before the treatment, but there were no notable differences at the day 42.
Conclusion: Infliximab therapy in Crohn's disease patients displayed a rapid influence on bone metabolism by enhancing bone formation and decreasing bone resorption. In addition to its mucosal effect affecting the bone homeostasis, indicate a further rationale usage of tumor necrosis factor-alpha blockade in the therapy of inflammatory bowel diseases.