A meta-analysis of randomized controlled trials comparing antibacterial therapy with placebo in Crohn's disease

Higher dose of simethicone decreases colonic bubbles and increases prep tolerance and quality of bowel prep: Meta-analysis of randomized controlled trials

BACKGROUND

Antifoaming agents, such as simethicone, may facilitate mucosal inspection during colonoscopy. However, conflicting results have been reported with regard to the impact of simethicone on quality of bowel preparation and adenoma detection rate (ADR).

AIM

To perform a meta-analysis of trials that have compared simethicone vs placebo during colonoscopy.

METHODS

A reproducible literature search of multiple medical databases yielded eleven studies (n = 2605) for inclusion. Studies were compared for quality of bowel preparation, bubbles quality, ADR, and tolerability. Two reviewers independently scored the identified studies for methodology and abstracted pertinent data. Pooling was conducted by both fixed-effects and random-effects models. Relative risk (RR) estimates with a 95% confidence interval (CI) were calculated. Heterogeneity was assessed by I-squared index (I²) statistics.

RESULTS

Patients’ demographic characteristics were comparable in all studies. Of the 2605 patients, 1300 were in the simethicone group, whereas 1305 were in the placebo group. Inadequate bowel preparation was much lower in the simethicone group than in the placebo group [13% vs 24.6%; RR = 0.51 (0.31-0.82); P < 0.0001]. The placebo group was more likely to have significant colonic bubbles than was the simethicone group [35% vs 8%; RR = 1.49 (1.25-1.76); P = 0.0001]. Use of simethicone resulted in a slight, statistically significant increase in ADR compared with the placebo group [26.6% vs 21.6%, RR = 1.07 (1.01-1.13); P = 0.02]. Higher doses of simethicone (> 478 mg) were more likely to result in significant reduction of inadequate bowel preparation, colonic bubbles, and to improve ADR.

CONCLUSION

Adding simethicone improved the quality of bowel preparation, visualization, tolerability, and, eventually, ADR.

Induction and maintenance treatment of inflammatory bowel disease: A comprehensive review

Ulcerative colitis (UC) and Crohn's disease (CD) are the two major types of inflammatory bowel disease (IBD). We conducted a comprehensive review of meta-analyses to summarize the reported effectiveness of different drugs for IBD. We performed a literature search and a total of 110 meta-analyses from 66 articles were summarized and re-analyzed (62 in UC and 48 in CD). In summary, 5-ASA was more effective than placebo in both induction and maintenance treatment of UC, but there were conflicting results on the effect of 5-ASA on the induction treatment or relapse of CD. The use of immunomodulatory agents in the induction or maintenance phase of UC and CD using immunomodulators appeared to be more effective than placebo, but the results were impacted by small number of patients, discordant results with the largest study and risk of biases. Anti-TNF-α and anti-integrin therapeutic antibodies in both, induction and maintenance, showed a better efficacy than placebo in a large proportion of patients analyzed. Other agents, such as probiotics, antibiotics, omega-3, were shown to be more effective than placebo, but the same issues arose as stated above with the use of immunomodulatory agents. In conclusion, we performed a comprehensive review of meta-analysis on comparative efficacy of pharmacotherapy used in the management of IBD. Our review will augment our understanding of the treatment of UC and CD by providing a guideline for interpreting the statistically significant findings and discusses the optimal choice for IBD treatment.

Antibiotics in IBD: Still a Role in the Biological Era?

Despite compelling evidence pointing to a critical role of gut microflora in inflammatory bowel disease (IBD) pathogenesis, the role of antibiotics in clinical practice remains limited, largely due to heterogeneous trials with often conflicting evidence. In this review, we revisit previous randomized controlled trials and high-quality uncontrolled studies in an effort to better elucidate the role of antibiotics in contemporary treatment algorithms. The most established role of antibiotics is in perianal Crohn's disease (CD), utilizing ciprofloxacin with or without metronidazole often as an adjunct to biological therapy. Evidence also points to a likely modest role of various antibiotic classes in mild to moderate luminal CD, including ciprofloxacin, metronidazole, azithromycin, and rifaximin. The benefit of metronidazole in preventing postoperative recurrence in CD is well reported; however, the long-term benefit of this intervention remains uncertain. The use of antibiotics in ulcerative colitis (UC) is even more controversial, but studies using broad-spectrum oral antibiotic cocktails have reported a possible role in acute severe colitis and chronic persistent UC. Similarly, the role of oral vancomycin and gentamicin in very early-onset IBD has interesting preliminary results. Adverse events of antibiotics, the resulting alterations in the microbiome with its associated unknown long-term sequela, and the emergence of antibiotic-resistant strains must be carefully balanced. Therefore, although antibiotics may be underused in the treatment of IBD, their integration into clinical practice must be approached judiciously and individually.

Similar outcomes for anti-tumor necrosis factor-α antibody and immunosuppressant following seton drainage in patients with Crohn's disease-related anal fistula

Anal fistula is common in patients with Crohn's disease (CD) and leads to significant morbidity. The efficacy of seton drainage combined with anti-tumor necrosis factor-α monoclonal antibody (anti-TNF-α) or immunosuppressant in the treatment of CD-related anal fistula remains unclear. The aim of the present study was to compare the efficacy between seton drainage combined with anti-TNF-α and seton drainage combined with immunosuppressant postoperatively on the treatment of CD-related anal fistula. A total of 65 patients with CD-related anal fistula who had received seton drainage combined with postoperative medication were divided into an antibiotics only group, anti-TNF-α group and immunosuppressant group; all patients were treated with antibiotics. Fistula closure, external orifice exudation rate and recurrence rate were assessed among these patients. The duration of follow-up ranged from 3 to 84 months with an average of 25.3 months. There were 11 (16.9%) cases of recurrence after seton drainage, 9 of which underwent a second seton drainage. In the total study group, 34 (52.3%) cases achieved complete fistula closure, and 10 (15.4%) cases showed external orifice exudation. No significant difference was found among these three groups, regarding fistula closure rate, closure time of fistula and recurrence rate. The external orifice exudation rate was significantly higher in the anti-TNF-α group compared with the antibiotics only group and immunosuppressant group (P=0.004 and P=0.026, respectively). Seton drainage is an effective treatment for CD-related anal fistula. The efficacy is similar whether combined with anti-TNF-α or immunosuppressant.

Inflammatory bowel disease meta-evidence and its challenges: is it time to restructure surgical research?

AIM

The aim of this study was to compare the methodological quality and input paper characteristics of systematic reviews and meta-analyses reported in the medical and surgical literature by performing a systematic 'overview of reviews'. Ulcerative colitis (UC) and Crohn's disease (CD) were used as the framework for this comparison as they are relatively common serious conditions, with both medical and surgical options for therapy.

METHOD

Medline, Embase, CINHAL and the Cochrane Database were searched to November 2013. Eligible papers were systematic reviews or meta-analyses that considered a question of therapy in CD or UC. Two independent reviewers selected the papers, extracted the data and scored their methodology using the AMSTAR scoring system. The papers were categorized into medical therapy (M), surgical therapy (S) or medical and surgical therapy (MS) groups. Following retrieval of the sample of meta-evidence papers, the original input studies used in their creation were identified and a search of Medline, Embase, CINHAL and the Cochrane Database was performed. A team of researchers then examined the collection of papers for bibliographic and financial information.

RESULTS

Five hundred papers were identified in the meta-evidence search, of which 118 were deemed eligible. There was a difference in the AMSTAR-rated average quality of the papers between the S and M group (S 7.36 vs M 8.75, P = 0.01). On average S papers were published in journals with a lower impact factor (S 3.26, M 5.04, MS 5.30, P < 0.001). S papers also showed more heterogeneity (I(2) ; S 37%, M 24%, MS 10%, P < 0.001). Some 25% of S meta-analyses used data-sets with significant heterogeneity (I(2) > 75%), compared with 8% of M meta-analyses and 3% of the MS meta-analyses. Some 5% of S papers were done on data sets that had I(2) values > 90%. There was no difference in the average number of papers assessed in each group, the average number of patients per meta-paper, the average time covered by the reviews, the average number of papers considered within each meta-analysis, or the average number of patients considered within each meta-analysis. Considering the conclusions of each meta-analysis, S meta-evidence was 50% more likely than M meta-evidence to be unable to make recommendations for practice. A total of 1499 original input papers were identified, of which 283 were used in more than one review. Within the non-repeated papers (n = 1023) the average impact factor within the S group was lower than that of the M and the MS groups (3.720 vs 11.230 vs 7.563, respectively; ANOVAP < 0.001). M papers had higher rates of pharmaceutical sponsorship than S papers (M 56% vs S 1%) and twice the level of government support (M 16% vs S 8%). Of note, 21% of M papers had corporate sponsorship but did not list any conflict of interest.

CONCLUSION

Compared with M meta-analyses, S meta-analyses in the UC and CD domain are more likely to be of poorer methodological quality, are of a greater degree of heterogeneity and less often offer a positive conclusion. The papers used to generate meta-evidence in M papers have a greater degree of corporate and government sponsorship, and are more likely to come from journals with higher impact factors.

Use of antibiotics in patients with Crohn's disease: a systematic review and meta-analysis

OBJECTIVES

Some studies have suggested that antibiotic treatment might be efficient for patients with active Crohn's disease (CD). However, the results are conflicting. The aim of this study was to summarize the available evidence on the efficacy of antibiotics, especially ciprofloxacin, in treating patients with CD.

METHODS

A literature search was conducted on the PubMed, Medline, Web of Science and Excerpta Medica Database (EMBASE) for manuscripts published until March 2014. Randomized controlled trials that mainly evaluated the efficacy of antibiotic treatment in patients with CD using clinical remission or response as the key outcome of interest were included. Intention-to-treat analyses were used to evaluate the relative risk (RR) and 95% confidence intervals (CI).

RESULTS

In all, 15 randomized placebo-controlled clinical trials involving 1407 participants were included in the meta-analysis. A pooled analysis revealed that compared with placebo, antibiotics benefited CD patients to a certain extent (RR 1.33, 95% CI 1.17-1.51, P < 0.00001). The random-effects model showed that there was no significant difference between patients treated with ciprofloxacin and placebo (combined RR 1.35, 95% CI 0.92-1.97, P = 0.12). However, ciprofloxacin exhibited significant clinical benefits in patients with perianal fistulas (RR 1.64, 95% CI 1.16-2.32, P = 0.005).

CONCLUSIONS

The utility of antibiotics was beneficial for patients with CD. Nevertheless, subgroup analyses indicated that treatment with ciprofloxacin alone was significantly efficient for CD patients with perianal fistulas.

Functional impacts of the intestinal microbiome in the pathogenesis of inflammatory bowel disease

: The human intestinal microbiome plays a critical role in human health and disease, including the pathogenesis of inflammatory bowel disease (IBD). Numerous studies have identified altered bacterial diversity and abundance at varying taxonomic levels through biopsies and fecal samples of patients with IBD and diseased model animals. However, inconsistent observations regarding the microbial compositions of such patients have hindered the efforts in assessing the etiological role of specific bacterial species in the pathophysiology of IBD. These observations highlight the importance of minimizing the confounding factors associated with IBD and the need for a standardized methodology to analyze well-defined microbial sampling sources in early IBD diagnosis. Furthermore, establishing the linkage between microbiota compositions with their function within the host system can provide new insights on the pathogenesis of IBD. Such research has been greatly facilitated by technological advances that include functional metagenomics coupled with proteomic and metabolomic profiling. This review provides updates on the composition of the microbiome in IBD and emphasizes microbiota dysbiosis-involved mechanisms. We highlight functional roles of specific bacterial groups in the development and management of IBD. Functional analyses of the microbiome may be the key to understanding the role of microbiota in the development and chronicity of IBD and reveal new strategies for therapeutic intervention.

Comparing medical treatments for Crohn's disease

The drugs available for inflammatory bowel disease are aminosalicylates, antibiotics, steroids, immunosuppressors and biologics. The effectiveness of these drugs has been evaluated in many randomized clinical trials, mainly versus placebo. Few studies have been conducted comparing the different drugs among themselves, owing to the methodological problems raised by comparative trials, such as sample size and blindness. This review focuses mainly on the randomized clinical trials that have compared different treatments. Of course comparisons are mainly between drugs used in a particular setting (mild, moderate and severe disease). However, on many occasions there is no homogeneity in these clinical settings, and therefore the results are difficult to interpret.

Variation in Antibiotic Use for Children Hospitalized With Inflammatory Bowel Disease Exacerbation: A Multicenter Validation Study

BACKGROUND

Antibiotics are often given for inflammatory bowel disease (IBD) exacerbations, but their use among pediatric inpatients has not been assessed. We aimed to validate administrative data for identifying hospitalizations for IBD exacerbation and to characterize antibiotic use for IBD exacerbations across children's hospitals.

METHODS

To validate administrative data for identifying IBD exacerbation, we reviewed charts of 409 patients with IBD at 3 US tertiary care children's hospitals. Using the case definition with optimal test characteristics, we identified 3450 children with 5063 hospitalizations for IBD exacerbation at 36 children's hospitals between January 1, 2007 and December 31, 2009, excluding those with diagnosis codes for specific bacterial infections. We estimated predicted and expected hospital-specific antibiotic utilization rates using mixed-effects logistic regression, adjusting for patient- and hospital-level factors.

RESULTS

Administrative codes for receipt of intravenous steroids or endoscopy provided 79% positive predictive value and 71% sensitivity for identifying hospitalizations for IBD exacerbation. Antibiotics were administered for ≥2 of the first 3 hospital days during 40.7% of IBD exacerbations in US children's hospitals; however, the proportion of patients receiving antibiotics varied significantly across hospitals from 27% to 71% (P < .001), despite adjustment for several patient- and hospital-level variables. Among those given antibiotics, the 3 most common regimens were metronidazole alone (26.9%), metronidazole with ciprofloxacin (10.3%), and ampicillin with gentamicin and metronidazole (7.0%).

CONCLUSIONS

Significant variability exists in antibiotic use for children hospitalized with IBD exacerbation, which is unexplained by disease severity or hospital volume. Further study should determine the optimal antibiotic therapy for this condition.

Gene-environment interactions in inflammatory bowel disease: microbiota and genes

A recent research workshop gave an update on the genetics of the inflammatory bowel diseases (IBD), Crohn's disease and ulcerative colitis. This mini-review summarises the updates of the gene-environmental interactions, especially those outlining the contribution of the gut microbiota to the pathogenesis of IBD.