Undiagnosed microscopic colitis: a hidden cause of chronic diarrhoea and a frequently missed treatment opportunity.

Microscopic colitis (MC) is a treatable cause of chronic, non-bloody, watery diarrhoea, but physicians (particularly in primary care) are less familiar with MC than with other causes of chronic diarrhoea. The colon in patients with MC is usually macroscopically normal. MC can only be diagnosed by histological examination of colonic biopsies (subepithelial collagen band >10 µm (collagenous colitis) or >20 intraepithelial lymphocytes per 100 epithelial cells (lymphocytic colitis), both with lamina propria inflammation). The UK National Health Service exerts downward pressure to minimise colonoscopy referrals. Furthermore, biopsies are often not taken according to guidelines. These factors work against MC diagnosis. In this review, we note the high incidence of MC (comparable to ulcerative colitis and Crohn's disease) and its symptomatic overlap with irritable bowel syndrome. We also highlight problems with the recommendation by National Health Service/National Institute for Health and Care Excellence guidelines for inflammatory bowel diseases that colonoscopy referrals should be based on a faecal calprotectin level of ≥100 µg/g. Faecal calprotectin is <100 µg/g in over half of individuals with active MC, building into the system a propensity to misdiagnose MC as irritable bowel syndrome. This raises important questions-how many patients with MC have already been misdiagnosed, and how do we address this silent burden? Clarity is needed around pathways for MC management; MC is poorly acknowledged by the UK healthcare system and it is unlikely that best practices are being followed adequately. There is an opportunity to identify and treat patients with MC more effectively.

Systematic review of time trends in the prevalence of Helicobacter pylori infection in China and the USA.

It has been suggested that the prevalence of Helicobacter pylori infection has stabilized in the USA and is decreasing in China. We conducted a systematic literature analysis to test this hypothesis. PubMed and Embase searches were conducted up to 19 January 2015. Trends in the prevalence of H. pylori infection over time were assessed by regression analysis using Microsoft Excel. Overall, 25 Chinese studies (contributing 28 datasets) and 11 US studies (contributing 11 datasets) were included. There was a significant decrease over time in the H. pylori infection prevalence for the Chinese studies overall (p = 0.00018) and when studies were limited to those that used serum immunoglobulin G (IgG) assays to detect H. pylori infection (p = 0.014; 20 datasets). The weighted mean prevalence of H. pylori infection was 66 % for rural Chinese populations and 47 % for urban Chinese populations. There was a significant trend towards a decreasing prevalence of H. pylori infection for studies that included only urban populations (p = 0.04; 9 datasets). This trend was no longer statistically significant when these studies were further restricted to those that used serum IgG assays to detect H. pylori infection, although this may have been because of low statistical power due to the small number of datasets available for this analysis (p = 0.28; 6 datasets). There were no significant trends in terms of changes in the prevalence of H. pylori infection over time for studies conducted in the USA. In conclusion, the prevalence of H. pylori infection is most likely decreasing in China, due to a combination of increasing urbanization, which we found to be associated with lower H. pylori infection rates, and possibly also decreasing rates of H. pylori infection within urban populations. This will probably result in a gradual decrease in peptic ulcer and gastric cancer rates in China over time.

Effect of comorbidity on mortality in patients with peptic ulcer bleeding: systematic review and meta-analysis.

OBJECTIVES: By systematic review and meta-analysis, we sought to assess the impact of comorbidity on short-term mortality in patients with peptic ulcer bleeding (PUB). METHODS: We conducted systematic searches in PubMed and Embase (January 1989-January 2010). Relative risks (RRs) were pooled across selected studies and an analysis of diagnostic test accuracy was performed to validate the results further. RESULTS: Of 1,572 identified studies, 16 were eligible for inclusion. Only three had a low risk of bias and the overall quality of evidence was low. The risk of death (30-day or in-hospital mortality) was significantly greater in PUB patients with comorbidity than in those without (RR: 4.44; 95% confidence interval (CI): 2.45-8.04). The pooled sensitivity for comorbidity predicting death in patients with PUB was 0.86 (95% CI: 0.66-0.95) and the pooled specificity was 0.53 (95% CI: 0.40-0.65). PUB patients with three or more comorbidities had a greater risk of dying than those with one or two (RR: 3.46; 95% CI: 1.34-8.89). All individual comorbidities that we assessed significantly increased the risk of death associated with PUB. However, RRs were higher for hepatic, renal, and malignant disease (range: 4.04-6.33; no significant heterogeneity) than for cardiovascular and respiratory disease and diabetes (2.39, 2.45, and 1.63, respectively; no significant heterogeneity). CONCLUSIONS: Underlying comorbidity is consistently associated with increased mortality in patients with PUB. The number and type of comorbidities in patients with PUB should be carefully evaluated and factored into initial management strategies.

Systematic review: Patterns of proton pump inhibitor use and adherence in gastroesophageal reflux disease.

BACKGROUND & AIMS: Variation in how proton pump inhibitors (PPIs) are taken likely influences their clinical effectiveness, and must be considered when estimating PPI failure rates. This review aimed to systematically investigate the literature on patterns of PPI use in patients with gastroesophageal reflux disease (GERD). METHODS: PubMed and Embase were searched (1989-May 2010) to identify observational studies providing information on patterns of PPI use in patients with GERD. RESULTS: Of 902 studies identified, 13 met prespecified selection criteria. Across 2 database studies, 53.8%-67.7% of patients with GERD had a medication possession ratio (MPR) of >0.80. Across 2 more database studies, the mean MPR for the study population was 0.68 to 0.84. Across 3 surveys, 70%-84% of patients reported daily PPI use. In 2 surveys, the presence and severity of reflux symptoms increased PPI adherence, as did Barrett's esophagus in another 2 studies. Across 3 surveys, 11%-22.2% of patients reported twice daily PPI use, and across 6 studies 11.0%-44.8% of patients took GERD medication in addition to a PPI. CONCLUSIONS: The results of this systematic review suggest that the majority of patients with GERD are relatively adherent to their PPI, although substantially different estimates were obtained using MPR data compared with surveys. Severe symptoms and the presence of Barrett's esophagus may increase PPI adherence, and other GERD medication is frequently taken in addition to a PPI. Limitations of studies in this area include inferring adherence from indirect MPR data, and recall bias associated with patient surveys.