Quantitative immunochemical FOBT has good sensitivity and specificity for detection of clinically significant neoplasia. Test performance in screening average-risk populations is not known.

Objective: Recurrence of Helicobacter pylori infection after eradication is rare in developed countries and more frequent in developing countries. Most recurrent cases are attributed to recrudescence (recolonization of the same strain within 12 months) rather than to reinfection (colonization with a new strain after more than 12 months). The aim of the study was to analyze recurrence rates in developed and developing countries and to deduce the relative roles of recrudescence and reinfection. Methods: The PubMed database was searched up to January 31, 2007 using the keywords " Helicobacter pylori " or " H. pylori " and "recurrence" or "recrudescence," or "reinfection." Only prospective case studies in adults that used the 13 C-urea breath test ( 13 CUBT) were included. Meta-analyses were performed with STATDIRECT Statistical software, version 2.6.1, StatsDirect Ltd, Chesire, UK. Results: The literature search yielded 10 studies of H. pylori recurrence in developed countries (3014 patients followed for 24-60 months) and 7 studies in developing countries (2071 patients followed for 12-60 months). The calculated annual recurrence rates were 2.67% and 13.00%, respectively. Nested metaanalysis of cases with a longer follow-up after eradication revealed an annual recurrence rate of 1.45% (RR 0.54) in developed countries and 12.00% (RR 0.92) in developing countries. Conclusions: The similarity of the annual recurrence rates during the first year after eradication and the annual recurrence rates in the second year after successful eradication in developing countries supports reinfection as the main cause in the second period. Therefore, a different approach for followup of H. pylori eradication may be needed between developed and developing countries. KeywordsHelicobacter pylori , eradication, recurrence, recrudescence, reinfection. Recurrence of Helicobacter pylori ( H. pylori ) infection after successful eradication is rare in developed countries and more frequent in developing countries [1]. Recrudescence (recolonization of the same strain) rather than reinfection (colonization with a new strain) is considered the more likely culprit in most cases [2]. However, this assumption is based on studies using heterogeneous testing methods and strategies, such as The aim of the present meta-analysis was to provide a more accurate assessment of H. pylori recurrence rates in developed and developing countries, and to deduce from these findings the relative roles of recrudescence and reinfection. To avoid the bias introduced by the different approaches used, we limited our database search to studies in adults in which the 13 CUBT was administered at completion of treatment, with a minimum follow-up of 12 months. We also performed a nested analysis of findings Reprint requests to

Our findings support the notion that colonoscopy is feasible and a suitable method for screening for CRC in asymptomatic people.

SUMMARY BackgroundFaecal occult blood tests (FOBT) are faulted by low sensitivity for advanced adenomatous polyps (AAP). Quantified, immunochemical, haemoglobin (Hb)-specific immunochemical FOBT (I-FOBT) measurements are now used for colorectal screening.

The use of aspirin/NSAIDS and anticoagulants was associated with a trend for increased sensitivity with no change in specificity for the detection of AAP/CRC. This study suggests that there is no need to stop these agents before I-FOBT testing.

SUMMARY BackgroundThe guaiac faecal occult blood test (G-FOBT), HemoccultSENSA, is sensitive for significant neoplasms [colorectal cancer (CRC), advanced adenomatous polyps (AAP)], but faulted by non-specificity for human haemoglobin (Hb). Quantified, Hb-specific, immunochemical faecal occult blood tests (I-FOBT) are now used.

BACKGROUND: Quantified, human hemoglobin (Hb)-specific, immunochemical fecal occult blood test (IFOBT) measurements are now used for colorectal cancer (CRC) screening. The objective was to evaluate sensitivity and specificity for CRC and advanced adenomatous polyps (APs) by the fecal Hb threshold used to determine a positive test and the number of IFOBTs prepared per test, so as to determine the least number of colonoscopies required to detect a neoplasm. METHODS: Cumulative data were analyzed from a prospective cross-sectional double-blind study of 1682 consecutive, ambulatory, nonbleeding colonoscopy patients who volunteered for IFOBTs, most of above average risk, from 3 ambulatory-endoscopy centers. Fecal Hb was measured in 3 samples and analyzed by an automated instrument, and the highest result !50 ng Hb/mL of buffer was related to findings. RESULTS: Colonoscopy identified CRC in 20 patients and advanced APs in 129. Sensitivity for either was best when any of 3 tests had !50 ng Hb/mL of buffer; sensitivity was 61.1% (95% confidence interval [CI], 53.2-68.9), and specificity was 87.8% (95% CI, 86.2-89.4). Positive tests identified 100% of CRCs and 55% of advanced APs every 3.1 colonoscopies. Sensitivity of a single test at the commonly used 100-ng Hb/mL threshold was lower at 31.5% (95% CI, 24.1-39.0) (P<.001), but specificity was higher at 96.4% (95% CI, 95.5-97.3) (P<.001). Positive tests identified 65% of CRCs and 26.4% of advanced APs every 2.2 colonoscopies. CONCLUSIONS: The fecal Hb cutoff chosen by the screener and the number of samples collected per patient determine sensitivity and specificity for CRC/advanced AP; these factors determine the number of colonoscopies needed for positive tests and neoplasia yield. This information provides guidelines for IFOBT screening. Limitations are 1-time screening and most examinees not being at average risk for CRC. Cancer 2010;116:2115-25.

SUMMARY BackgroundInflammatory bowel disease (IBD) patients undergo multiple radiological evaluations.