Chronic Abdominal Wall Pain: An Under-Recognized Diagnosis Leading to Unnecessary Testing.

Chronic abdominal wall pain (CAWP) refers to a condition wherein pain originates from the abdominal wall itself rather than the underlying viscera. According to various estimates, 10% to 30% of patients with chronic abdominal pain are eventually diagnosed with CAWP, usually after expensive testing has failed to uncover another etiology. The most common cause of CAWP is anterior cutaneous nerve entrapment syndrome. The diagnosis of CAWP is made using an oft-forgotten physical examination finding known as Carnett's sign, where focal abdominal tenderness is either the same or worsened during contraction of the abdominal musculature. CAWP can be confirmed by response to trigger point injection of local anesthetic. Once diagnosis is made, treatment ranges from conservative management to trigger point injection and in refractory cases, even surgery. This review provides an overview of CAWP, discusses the cost and implications of a missed diagnosis, compares somatic versus visceral innervation, describes the pathophysiology of nerve entrapment, and reviews the evidence behind available treatment modalities.

Measurement of Fractional Exhaled Nitric Oxide as a Marker of Disease Activity in Inflammatory Bowel Disease.

BACKGROUND AND AIMS: Definitive diagnosis of IBD requires endoscopic and pathologic confirmation. These tools are also used to classify disease activity. Our aim was to determine if the fractional exhaled nitric oxide (FeNO) could be utilized to screen for IBD and assess for disease activity. METHODS: We matched weighted IBD cases and controls from the 2009-2010 NHANES dataset. All subjects underwent measurement of FeNO using standardized techniques. We assessed for potential confounders for FeNO measurement including age, height, and asthma. For IBD subjects, we used the presence of diarrhea, fatigue, and weight loss as a proxy for IBD activity. Laboratory parameters examined to estimate disease activity included anemia (≤ 10 g/dl), iron deficiency (ferritin ≤ 20 ng/ml), hypoalbuminemia (≤ 3.2 g/dl), and CRP (≥ 1.1 mg/dl). RESULTS: The weighted sample represented 199,414,901 subjects. The weighted prevalence of IBD was 2,084,895 (1.0%). IBD subjects had nearly the same FeNO level as those without IBD (17.0 ± 16.2 vs. 16.7 ± 14.5 ppb). The odds of a FeNO > 25 ppb was half (OR=0.501; 95% CI 0.497-0.504) for subjects with IBD compared to those without IBD after controlling for confounders. The AUROC curve for FeNO was 0.47 (0.35-0.59). FeNO levels were not higher in patients with laboratory values suggestive of active disease. FeNO levels were higher in IBD patients with diarrhea, rectal urgency, and fatigue but were lower in those with unintentional weight loss. CONCLUSION: Measurement of FeNO does not appear to be useful to screen for IBD or assess disease activity.

Administrative Database Research Overestimates the Rate of Interval Colon Cancer.

GOALS: Our study reexamines the prevalence of interval colorectal cancer (I-CRC) by manually reviewing CRC cases at a single institution. BACKGROUND: In 2% to 8% of patients with CRC, diagnosis occurs during the interval 6 to 36 months after a cancer-free colonoscopy. Rates are often determined by linking the date of colonoscopy with cancer registry information. STUDY: We examined all colonoscopies from 1993 to 2011. These examinations were linked with Pennsylvania Cancer Registry data. Matched charts were manually reviewed. We determined whether the CRC was "prevalent" or, for patients with a previous colonoscopy, whether they were interval or noninterval based on time from last colonoscopy. For interval cases, we identified "administrative errors" that could falsely increase the number of reported I-CRC. RESULTS: Over the study period, 43,661 colonoscopies were performed, with 1147 (2.6%) positive for CRC after excluding cases (n=52) in which patients had IBD, previous surgery, or nonadenocarcinoma malignancy. Prevalent CRCs totaled 1062 (92.6%). Noninterval CRCs (diagnosed over 36 mo from index colonoscopy) were present in 40 (3.5%). There remained 45 (3.9%) potential I-CRC cases. However, after manual review, 21 cases were found to be administrative errors. Therefore, the accurate proportion of colonoscopies that found an I-CRC was 2.1% (95% confidence interval, 1.5%-3.2%). CONCLUSIONS: The prevalence of I-CRC at our institution before adjustment was comparable with previously reported rates. This proportion was 47% lower after adjusting for administrative errors placing our figure at the lower end of reported I-CRC incidence. Reported rates of I-CRC may be falsely elevated due to errors unique to merging administrative databases.