Importance of diarrhea in evaluating constipation in irritable bowel syndrome clinical studies.

BACKGROUND: Irritable bowel syndrome (IBS) is a chronic functional gastrointestinal disorder characterized by alterations in bowel function, abdominal discomfort, and bloating. The symptoms of IBS vary widely between constipation and diarrhea predominance. In this study, we examine "constipation minus diarrhea" score (C-D) to account for the contribution of diarrhea and to create a reliable method for predicting constipation predominance in IBS. METHODS: A nested study was conducted in participants with IBS by Rome I criteria. After consent, they completed a daily stool diary for 1 week. This included recording frequency of bowel movements and describing consistency of stool using the Bristol stool scale. After submitting their diaries, participants rated their bowel symptoms using a visual analog score (VAS) scale from 0 to 100 mm, with 100 mm representing maximum severity. VAS scores for C, D, and C-D were subsequently compared with the true stool events of the previous week by stool diary to validate the potential usefulness of the simple C-D method. RESULTS: Eighty-four participants with IBS completed stool diaries and VAS surveys for bowel symptoms, from which C-D scores were compiled. By correcting for the predominance of constipation compared with diarrhea, C-D scores predicted constipation based on the frequency of bowel movements and Bristol stool score. Furthermore, a second method was used to validate the C-D technique by comparing the mean C-D score in participants with constipation (≤3 d with bowel movement in previous week). In this case, the mean C-D score was 74.1 ± 3.8 compared with -3.0 ± 5.9 for patients with >3 days with bowel movement in that week (P<0.001). Although the constipation severity alone also distinguished these 2 groups, the difference was less impressive (P<0.01). In participants with mean Bristol stool scores of ≤2 in the preceding week, the C-D mean score was 25.4 ± 6.1 compared with participants having mean Bristol stool score of >2 where the C-D was -11.1 ± 5.9 (P<0.01). Using constipation severity by VAS alone, there was no significant difference between these same 2 Bristol stool categories (P=0.29). CONCLUSIONS: IBS patients' self-assessment of constipation and diarrhea severity using the C-D score is an effective predictor of C-IBS and constipation severity. The C-D score may be a useful tool in future IBS constipation trials, as it seems to predict constipation and it correlates well with stool diaries.

Methane on breath testing is associated with constipation: a systematic review and meta-analysis.

BACKGROUND: A growing body of literature suggests an association between methane and constipation. Studies also link degree of methane production to severity of constipation and have shown constipation is improved following antibiotics. AIMS: We aim to conduct a systematic review and meta-analysis to examine the cumulative evidence regarding the association between methane and constipation. METHODS: A literature search was performed using MEDLINE and Embase to identify studies where the presence (or absence) of methane was assessed in constipated subjects. Search terms included "methane," "breath test," "constipation," "motility," "transit," "irritable bowel syndrome" and/or "IBS." Pooled odds ratios were generated using a random effects model. In a separate analysis, studies that measured intestinal transit in methane and non-methane subjects were systematically reviewed. RESULTS: Nine studies met inclusion criteria for the meta-analysis. Among these, 1,277 subjects were examined by breath testing (N = 319 methane producers and N = 958 methane non-producers). Pooling all studies, a significant association was found between methane on breath test and constipation (OR = 3.51, CI = 2.00-6.16). Among adults only, methane was significantly associated with constipation (OR = 3.47, CI = 1.84-6.54). Similar results were seen when only examining subjects with IBS (OR = 3.60, CI = 1.61-8.06). The systematic review identified eight additional papers which all demonstrated an association between methane and delayed transit. CONCLUSIONS: We demonstrate that methane present on breath testing is significantly associated with constipation in both IBS and functional constipation. These results suggest there may be merit in using breath testing in constipation. Moreover, methane may be used to identify candidates for antibiotic treatment of constipation.

Abnormal breath testing in IBS: a meta-analysis.

BACKGROUND: Recent evidence suggests a role for enteric bacteria in the development of symptoms in subjects with irritable bowel syndrome (IBS). The concept was initially based on the common finding of an abnormal lactulose breath test to suggest the presence of small intestinal bacterial overgrowth (SIBO). Despite successful antibiotic studies based on these findings, the premise of bacterial overgrowth was met with skepticism due to the perceived inaccuracies of breath testing in humans. In this study, we conduct a systematic review and meta-analysis of the studies using breath testing in IBS subjects with comparison to healthy controls. METHODS: A literature search was conducted to identify studies in which breath testing was conducted in subjects with IBS. Once abstract titles were identified, studies that examined breath testing in a case-control fashion were identified for paper review. After exclusion criteria were applied, the remaining papers were examined using meta-analysis, among which the prevalence of an abnormal breath test in IBS subjects was compared. Further analysis was conducted among studies with appropriate age- and sex-matched controls. RESULTS: Eleven studies met criteria for inclusion in the meta-analysis. Although heterogeneity was identified among studies on the basis of substrate used, lactulose was the most common substrate. In pooling the 11 studies, breath testing was more often abnormal among IBS subjects than health controls (OR=4.46, 95% CI=1.69-11.80). This was further evident in more appropriately designed age- and sex-matched studies (OR=9.64, 95% CI=4.26-21.82). The overall sensitivity and specificity for breath testing in separating IBS from healthy controls was 43.6 and 83.6%. CONCLUSIONS: This study demonstrates that the breath test findings in IBS appear to be valid. While this meta-analysis does not suggest that the breath test findings imply SIBO, the abnormal fermentation timing and dynamics of the breath test findings support a role for abnormal intestinal bacterial distribution in IBS.

Hepcidin is a key mediator of anemia of inflammation in Crohn's disease.

UNLABELLED: Anemia often complicates the course of Inflammatory Bowel Disease (IBD). Hepcidin, a liver-produced peptide hormone, is a key mediator of anemia of chronic disease (ACD). We hypothesized that hepcidin is significantly elevated in anemic CD patients and that hepcidin may cause iron restriction and, therefore, mediate ACD. METHODS: We enrolled 17 patients with CD and ACD recruited from the Cedars-Sinai IBD Center. Routine blood tests included hemoglobin (Hgb), hematocrit, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP). Anemia was defined as hemoglobin <12g/dL and <13.5g/dL, in men and women, respectively. ACD was diagnosed on the basis of a combination of the following: a) normal or elevated ferritin b) lowered serum iron and total iron binding capacity and c) normal percent iron saturation. Serum and urine hepcidin, as well as IL-6 levels were also measured. Patients with documented iron-deficiency anemia were excluded. RESULTS: There was an excellent correlation between urine (expressed as ng/mg of creatinine) and serum hepcidin levels expressed as ng/ml (r=0.853, p<0.001). We also found a strong positive correlation between serum hepcidin and ferritin levels (r=0.723, p=0.0015). There was a positive correlation between serum hepcidin and IL-6 levels (r=0.546, p=0.023). We found a strong negative correlation between serum hepcidin concentrations and Hgb levels (r=0.528, p=0.029). CONCLUSION: We demonstrate that ACD in CD is characterized by high serum IL-6 and hepcidin levels, which negatively correlate with Hgb levels. Our data support the hypothesis that IL-6-driven hepcidin production mediates ACD in patients with CD.

Evaluation of peripapillary lymphocytosis and lymphocytic esophagitis in adult inflammatory bowel disease.

Lymphocytic esophagitis (LE) is a newly described entity characterized histopathologically by peripapillary lymphocytosis (PL) without significant granulocytes (neutrophils and eosinophils). In an initial study, a significant portion of patients with LE had Crohn's disease (CD). A subsequent study revealed LE in one quarter of children with CD. The aim of this study was to test the hypothesis that LE is associated with adult inflammatory bowel disease (IBD) and assess the disease variables that link LE and IBD. Random esophageal biopsies from consecutive adults with CD, ulcerative colitis (UC), or indeterminate colitis (IC) were evaluated. The numbers of lymphocytes, eosinophils, and neutrophils were counted from 3 high-power fields (HPF) in each specimen. Four of 47 patients (8.5%; 3/30 CD, 1/15 UC, and 0/2 IC) had PL (esophageal biopsies with ≥50 lymphocytes/HPF; mean, 100.5±31.1/HPF). A significant number of granulocytes were seen in biopsies from 3 of the 4 patients with PL, leaving 1 who met criteria for LE (PL without significant granulocytes). PL was associated with a higher erythrocyte sedimentation rate (90.3±17.6 mm/hr vs 24.5±3.6 mm/hr; P<.001) and C-reactive protein level (5.5±2.2 mg/dL vs 1.0±0.2 mg/dL; P<.001), with risk ratios of 2.06 (95% confidence interval [CI], 1.45-2.93; P=.031) and 3.56 (95% CI, 2.04-6.19; P=.033), respectively, for elevated values. All patients with PL had a relapsing CD course. The mean Harvey-Bradshaw index (HBI) was higher in these patients (8.5±0.6 vs 4.3±0.7; P=.026), with a risk ratio of 4.78 for moderate-to-severe disease (95% CI, 2.67-8.54; P=.004). We found a less frequent association between IBD and LE than was previously reported. This may be due to differences between pediatric and adult IBD. Alternatively, it may be methodologic because, unlike in previous reports, we evaluated consecutive patients with IBD. PL was associated with elevated inflammatory markers and HBI. These observations suggest that PL may be a marker of disease activity in IBD.

Intestinal methane production in obese individuals is associated with a higher body mass index.

BACKGROUND: Obesity is an epidemic that affects 1 in 3 individuals in the United States, and recent evidence suggests that enteric microbiota may play a significant role in the development of obesity. This study evaluated the association between methanogenic archaea and obesity in human subjects. METHODS: Subjects with a body mass index (BMI) of 30 kg/m² or higher were prospectively recruited from the weight loss program of a tertiary care medical center. Subjects who met the study's inclusion criteria were asked to complete a questionnaire that included a series of visual analogue scores for bowel symptom severities. Subjects then provided a single end-expiratory breath sample to quantitate methane levels. Bivariate and multivariate analyses were used to determine associations with BMI. RESULTS: A total of 58 patients qualified for enrollment. Twenty percent of patients (n = 12) had breath test results that were positive for methane (>3 parts per million [ppm]), with a mean breath methane concentration of 12.2±3.1 ppm. BMI was significantly higher in methane-positive subjects (45.2±2.3 kg/m²) than in methane-negative subjects (38.5±0.8 kg/m²; P=.001). Methane-positive subjects also had a greater severity of constipation than methane-negative subjects (21.3±6.4 vs 9.5±2.4; P=.043). Multiple regression analysis illustrated a significant association between BMI and methane, constipation, and antidepressant use. However, methane remained an independent predictor of elevated BMI when controlling for antidepressant use (P<.001) and when controlling for both constipation and antidepressant use (6.55 kg/m² greater BMI; P=.003). CONCLUSION: This is the first human study to demonstrate that a higher concentration of methane detected by breath testing is a predictor of significantly greater obesity in overweight subjects.

Colorectal cancer screening and surveillance in Crohn's colitis.

AIMS: To assess colonoscopic screening and surveillance for detecting neoplasia in patients with long-standing colonic Crohn's disease (CD). PATIENTS AND METHODS: Colonoscopy and biopsy records from patients with colonic CD were evaluated at the Cedars-Sinai Inflammatory Bowel Disease Center during a 17-year period (1992-2009). RESULTS: Overall, 904 screening and surveillance examinations were performed on 411 patients with Crohn's colitis (mean 2.2 examinations per patient). The screening and surveillance examinations detected neoplasia in 5.6% of the patient population; 2.7% had low-grade dysplasia (LGD) (n=11), 0.7% had high-grade dysplasia (HGD) (n=3), and 2.2% had carcinoma (anal carcinoma n=3; rectal carcinoma n=6). Mean age of CD diagnosis was 25.6±0.8 years in those with normal examinations, compared to 17.7±2.7 years (p<0.001) in those with HGD, 36.85±1.43 in those with LGD (p=0.021) and 28.32±3.24 years in those with any dysplasia/cancer (p=0.034). Disease duration in patients with normal examinations was 19.1±0.5 years, compared to 36.8±4.4 years (p<0.001) in HGD, 16.88±2.59 in those with LGD (p=0.253) and 30.68±4.03 years in those with any dysplasia/cancer (p=0.152). The mean interval between examinations was higher in HGD (31.5±9.4 months) compared to those with normal colonoscopies (12.92±1.250 months; p=0.002). CONCLUSIONS: We detected cancer or dysplasia in 5.6% of patients with long-standing Crohn's colitis enrolled in a screening and surveillance program. Younger age at diagnosis of CD, longer disease course, and greater interval between exams were risk factors for the development of dysplasia.

Dysplasia and cancer in inflammatory bowel disease.

Inflammatory bowel disease (IBD) is a chronic gastrointestinal disease associated with an increased risk of colorectal cancer (CRC). Although CRC occurs in a minority of IBD patients (1%), it carries a high mortality and accounts for 20% of IBD-related mortality. Established risk factors for the development of CRC in IBD include disease duration of 8 years or more, family history of CRC, extensive colitis and primary sclerosing cholangitis. Meticulous colonoscopy and anti-inflammatory medications can reduce the risk of developing CRC. The future of IBD surveillance involves the use of novel endoscopic techniques (chromoendoscopy, narrow-band imaging, confocal laser endomicroscopy and autofluorescence) to enhance colonoscopic accuracy, in concert with chemopreventative medications to help reduce the risk of CRC in IBD.

Antibiotics for the treatment of irritable bowel syndrome.

Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder with an estimated worldwide prevalence of 10-20%. IBS can be associated with severe gastrointestinal symptoms, including abdominal pain, bloating, and altered bowel function. Although the causes of IBS remain undefined, recent research has increasingly suggested roles for gut flora in IBS. These roles involve postinfectious IBS, which can occur after a single episode of acute gastroenteritis, and small intestinal bacterial overgrowth, in which elevated populations of aerobic and anaerobic bacteria cause abdominal pain and altered bowel function. More recently, potential roles for methanogens in contributing to IBS subtypes have also been identified. In this paper, we review the different mechanisms by which gut flora may contribute to IBS and also discuss the efficacy and safety of various antibiotic therapies for treating IBS symptoms.

Current national incidence, trends, and health care resource utilization of cleft lip-cleft palate.

BACKGROUND: Available reports on the epidemiology of cleft lip, cleft palate, and cleft lip-cleft palate have been numerous yet inconsistent, and have originated only from institutional or regional studies. The need for current national data and the recognition of recent trends exists. METHODS: The authors examined the Kids' Inpatient Database to obtain national information on pediatric orofacial cleft discharges from 1997 to 2007. The authors examined patient and hospital characteristics to discern differences in use of care, hospital charges, type of hospital, untoward events, and other variables among various groups. A detailed investigation searching for significant trends during the 6-year study period was also conducted. RESULTS: Trends appreciated from 1997 to 2007 included (1) an increase in cleft operations performed at teaching hospitals compared with nonteaching hospitals (teaching increased 13.4 percent and nonteaching decreased 15.8 percent); (2) an increase in the mean overall charges (74.5 percent increase; p < 0.001) and a rate of rise higher than that of aggregate charges (60 percent; p < 0.001); and (3) a lower rate of perioperative complications in teaching hospitals from 2000 to 2007, ranging from 14 to 27 percent less than in nonteaching hospitals. CONCLUSIONS: The authors' data show that there is a current trend of cleft patients receiving treatment at teaching hospitals, with higher costs and decreasing complications. An understanding of such trends and disparities in resource use among various patient, hospital, and geographic settings is important for physicians and policy makers.

Autoimmune hemolytic anemia in treatment-naive chronic hepatitis C infection: a case report and review of literature.

The hepatitis C virus (HCV) is the most common blood-borne pathogen and currently infects over two hundred and fifty million individuals worldwide. Chronic HCV infection may result in cirrhosis, hepatocellular carcinoma, and liver failure. An exceedingly rare extrahepatic manifestation of HCV is autoimmune hemolytic anemia (AIHA). We discuss an interesting case of direct Coombs'-positive AIHA in a treatment-naive 53-year-old male with a past medical history of HCV cirrhosis, genotype 3a, who presented with fatigue, abdominal pain, and jaundice. Complete blood cell count demonstrated anemia, thrombocytopenia, elevated mean corpuscular hemoglobin and corpuscular volume worrisome for hemolytic anemia. Upon further workup, the patient was found to have increased bilirubin, reticulocyte count, and lactate dehydrogenase with concomitant direct Coombs'-positive test, consistent with the diagnosis of AIHA. A comprehensive workup was conducted to elucidate the underlying etiology of the AIHA, including malignancy, systemic lupus erythematosus (SLE), and medication side-effects. Malignancy was ruled out with an imaging and bone marrow biopsy. SLE was subsequently eliminated with a negative anti-nuclear antibody (ANA), and the patient had never received ribavirin, interferon, cephalosporins or other medications associated with drug-induced immune hemolytic anemia (DI-IHA). While the relationship between DI-IHA and HCV is well-described in the literature, primary AIHA in treatment-naive patients is a rare and intriguing extrahepatic manifestation of HCV and only four reports have been described in the literature. Given the prevalence of HCV and this interesting extrahepatic manifestation, HCV testing should be considered in patients presenting with AIHA with an otherwise negative workup and a history of parenteral or lifestyle risk factors.

A role for neutral sphingomyelinase activation in the inhibition of LPS action by phospholipid oxidation products.

Previous studies from our laboratory and others presented evidence that oxidized 1-palmitoyl-2-arachidonyl-sn-glycero-3-phosphatidylcholine (OxPAPC) and oxidized 1-palmitoyl-2-arachidonyl-sn-glycero-3-phosphatidylethanolamine can inhibit lipopolysaccharide (LPS)-mediated induction of interleukin-8 (IL-8) in endothelial cells. Using synthetic derivatives of phosphatidylethanolamine, we now demonstrate that phospholipid oxidation products containing alpha,beta-unsaturated carboxylic acids are the most active inhibitors we examined. 5-Keto-6-octendioic acid ester of 2-phosphatidylcholine (KOdiA-PC) was 500-fold more inhibitory than OxPAPC, being active in the nanomolar range. Our studies in human aortic endothelial cells identify one important mechanism of the inhibitory response as involving the activation of neutral sphingomyelinase. There is evidence that Toll-like receptor-4 and other members of the LPS receptor complex must be colocalized to the caveolar/lipid raft region of the cell, where sphingomyelin is enriched, for effective LPS signaling. Previous work from our laboratory suggested that OxPAPC could disrupt this caveolar fraction. These studies present evidence that OxPAPC activates sphingomyelinase, increasing the levels of 16:0, 22:0, and 24:0 ceramide and that the neutral sphingomyelinase inhibitor GW4869 reduces the inhibitory effect of OxPAPC and KOdiA-PC. We also show that cell-permeant C6 ceramide, like OxPAPC, causes the inhibition of LPS-induced IL-8 synthesis and alters caveolin distribution similar to OxPAPC. Together, these data identify a new pathway by which oxidized phospholipids inhibit LPS action involving the activation of neutral sphingomyelinase, resulting in a change in caveolin distribution. Furthermore, we identify specific oxidized phospholipids responsible for this inhibition.