Faculty Bibliography

BACKGROUND: Infliximab is used to treat moderate to severe Crohn's disease (CD), but its efficacy varies. Although cigarette smoking worsens CD, its impact on the infliximab response is unknown. We conducted a systematic review and meta-analysis of clinical trials to determine the effect of smoking on the induction response to infliximab. METHODS: A systematic search was performed of MEDLINE, EMBASE, CINAHL, the Cochrane central register of controlled trials, the Cochrane IBD Group Specialized Trials Register for publications, and abstracts from major conferences from January 1996 to December 2010. Random effects meta-analysis using the Mantel-Haenszel method was conducted. Heterogeneity across studies was assessed using the Q statistic, the I2 statistic, and tau2. RESULTS: We identified 12 articles; four were excluded due to use of non-validated scoring systems.The remaining eight included a total of 1658 patients, with 649 active smokers. Luminal response was assessed by the Crohn's Disease Activity Index in four studies (three of which included fistula response) and the Harvey-Bradshaw index in two (both including fistula response), and two studies examined only the fistula response. The relative risk for response to infliximab among smokers was 0.99 (95% CI 0.88-1.11) (tau2 = 0.0143). Analyses of the five studies examining both inflammatory and fistulizing CD were similar to the analysis of all eight studies. The pooled relative risk was 0.92 (95% CI 0.80-1.06) (tau2 = 0.0154). CONCLUSION: Though smoking worsens CD, this meta-analysis does not show a negative effect of smoking on initial response to infliximab. This must be viewed in the proper context, as long-term maintenance of response may yet be influenced by smoking status.

: Chronic proctitis refers to persistent or relapsing inflammation of the rectum, which results from a wide range of etiologies with various pathogenic mechanisms. The patients may share similar clinical presentations. Ulcerative proctitis, chronic radiation proctitis or proctopathy, and diversion proctitis are the 3 most common forms of chronic proctitis. Although the diagnosis of these disease entities may be straightforward in the most instances based on the clinical history, endoscopic, and histologic features, differential diagnosis may sometimes become problematic, especially when their etiologies and the disease processes overlap. The treatment for the 3 forms of chronic proctitis is different, which may shed some lights on their pathogenetic pathway. This article provides an overview of the latest data on the clinical features, etiologies, diagnosis, and management of ulcerative proctitis, chronic radiation proctopathy, and diversion proctitis.