Stool Collection Research Articles

Stool DNA screening for colorectal neoplasia: biological and technical basis for high detection rates

Colorectal cancer (CRC), the second most common cause of cancer-related mortality worldwide, is preventable with effective screening and removal of precursor lesions. Yet, screening efforts have been hampered by low participation rates and by performance limitations of the screening tools themselves. Stool DNA testing has emerged as a biologically rational and user-friendly strategy for the non-invasive detection of both CRC and critical precursor lesions. Unlike most conventional screening tools, stool DNA testing detects proximal and distal colorectal neoplasms equally well. Several key technical advances have led to increasingly accurate approaches for stool DNA testing including use of a DNA preservative buffer with stool collection, efficient target capture and amplification methods, broadly informative marker panels, and automated assay components. Based on recent studies, advanced multi-marker stool DNA tests including methylated markers, mutation markers and an assessment of faecal haemoglobin have been shown to detect CRC at sensitivities of 85% and higher and adenomas >1 cm at 60% and higher in a case-control environment. If the high accuracy of multi-marker stool tests is corroborated in multicentre screening studies on average-risk persons currently underway, then these stool tests could influence our CRC screening paradigm.This review discusses the biological basis, key technical advances, and recent clinical performance validation of stool DNA testing.

Partial Pancreatic Resection for Pancreatic Malignancy Is Associated with Sustained Pancreatic Exocrine Failure and Reduced Quality of Life: A Prospective Study

Objectives: Pancreatic resection for cancer may produce pancreatic exocrine insufficiency (PEI), which is poorly understood. This study examined the coefficient of fat absorption (CFA), symptoms, quality of life (QoL) and the accuracy of faecal elastase-1 (FE-1) measurement to predict PEI. Methods: Forty patients were analysed following resection for pancreatic malignancy. The primary endpoint was PEI diagnosis defined by CFA !93%; secondary endpoints were PEI diagnosis using FE-1 <200 μg/g, body mass index (BMI), and symptom and QoL analysis. Interventions were 3-day stool collection, EORTC QLQ-C30 (version 1) questionnaire and patient's diary, at 6 weeks and 3,6 and 12 months after surgery. Results: CFA <93% was presentin 67% of patients at 6 weeks and in 55% at 12 months. PEI using FE-1 was present in 77 and 83% of patients, respectively. No significant changes between time-points were observed. Sensitivity, specificity, PPV, NPV and accuracy for FE-1 in detecting CFA <93% were 91, 35, 70, 71 and 70%, respectively. CFA and FE-1 levels were uncorrelated. Overall, QoL increased at 6 (p = 0.0212) and 12 (p < 0.0001) months after surgery, mainly driven by physical, role and social functioning, and by appetite. Importantly, however, BMI and symptoms were unaffected by PEI, which suggests a subclinical presentation; such patients had attributes indicating poorer QoL (notably insomnia, p = 0.0012). Conclusions: PEI was common and sustained following resection and not associated with significant symptoms. These patients had a tendency toward poorer QoL. FE-1 is a poor surrogate for diagnosing impaired fat absorption. Postoperative pancreatic enzyme replacement should be considered more routinely.

Evaluation of Stool Collections to Measure Efficacy of PERT in Subjects With Exocrine Pancreatic Insufficiency

The standard measure of pancreatic enzyme replacement therapy (PERT) efficacy in treating exocrine pancreatic insufficiency (EPI) is the coefficient of fat absorption (CFA). CFA measurement involves 72-hour stool collection, which presents a logistical challenge because, although the test may be performed on an outpatient basis in clinical practice, hospitalization is needed if assurance of complete collection and 100% compliance is required, for example, in controlled situations such as clinical trials. Our aim was to investigate sparse stool sample collection as an alternative to complete 72-hour collection for measurement of stool fat in subjects with EPI. Prospective data analysis from a previously published, double-blind, randomized, placebo-controlled, 2-period crossover trial in subjects ages 7 to 11 years with EPI caused by cystic fibrosis. Percentage fat (PF) data from sparse stool samples were compared with 72-hour CFA values as a dichotomous variable (<80%, ≥80%), with evaluation of sensitivity, specificity, and positive predictive value. Area under the curve values were obtained from receiver operating characteristic plots of sensitivity versus 1-specificity. Twelve subjects provided samples for this analysis. Multiple-sample PF values ≤30% were greatly predictive for CFA values ≥80%, as shown by positive predictive value, sensitivity, and specificity values ≥0.89, with high accuracy (AUCs ≥0.93). Sparse stool sampling for PF analysis appears to be a valid, practical alternative to 72-hour CFA determination and has potential as a screening tool in clinical practice to identify both suboptimal dosing in subjects with EPI receiving PERT and substantial fat malabsorption in subjects not receiving PERT.

Is Moderate Red Wine Consumption Safe in Inactive Inflammatory Bowel Disease?

Background: Alcohol consumption is a potential trigger for inflammatory bowel disease (IBD) flare because of alcohol-induced oxidative stress and its deleterious effects on gut barrier function. Additionally, we have recently shown that alcohol consumption is associated with more symptoms in IBD. However, it is not known whether moderate daily alcohol consumption can modify IBD disease activity. To test what effects alcohol may have on patients with IBD, we evaluated the effect of moderate daily red wine for 1 week on two factors associated with recurrent IBD disease activity: intestinal permeability and stool calprotectin. Methods: To assess the effects of moderate daily alcohol consumption on intestinal permeability and inflammation, we recruited 21 patients: 8 with inactive ulcerative colitis (UC), 6 with inactive Crohn’s disease (CD), and 7 healthy controls. All participants with IBD completed a validated questionnaire on disease activity (Crohn’s disease activity index or ulcerative colitis clinical activity index), to confirm they had inactive disease. All subjects then underwent a baseline assessment that included a blood draw, urine collection after sugar challenge, and stool collection. Subjects then consumed 1–3 glasses of red wine a day for 1 week (approx. 0.4 g EtOH/kg), and repeated the three measures. Results: No subjects flared during the study. Moderate alcohol consumption did not significantly change either clinical disease activity scores or C-reactive protein. In contrast to healthy subjects, daily consumption of red wine significantly (1) decreased stool calprotectin in IBD subjects from baseline (p = 0.001) and (2) increased intestinal permeability as measured by urinary lactulose/mannitol excretion (marker of small bowel permeability) in CD (p = 0.028) or urinary sucralose secretion (marker of large bowel permeability) in UC (p = 0.012). Conclusions: One week of moderate consumption of red wine in inactive IBD was associated with a significant decrease in stool calprotectin and a significant increase in intestinal permeability. Our data suggests that patients with inactive IBD who drink red wine daily may be at an increased long-term risk for disease relapse.

P2-347 10 years of Polio/AFP surveillance in Lebanon: 2000–2009

BackgroundEver since the 1988 poliomyelitis eradication global initiative, cases have been drastically decreasing; however, four countries remain polio reservoir sources for virus exportation. In Lebanon, the last two indigenous cases...

High alpha‐1 antitrypsin clearance predicts severity of gut graft‐versus‐host disease (GVHD) in children

The clinical evaluation and management of gut GVHD is a significant challenge in pediatric HSCT. It is often difficult to obtain pathological evidence to confirm diagnosis and/or to determine response to treatment. The severity of the disease itself may not be related to just the classic symptom of diarrhea. The objectives of this study were to prospectively evaluate patients with suspected gut GVHD for PLE as measured by AATC in stools at two different times for each patient and to compare the severity of the PLE with the severity of clinical acute gut GVHD. Thirteen patients were suspected of gut GVHD by clinical criteria (diarrhea > 10 mL/kg/24 h); one patient was excluded for being unable to complete the stool collection. Therefore, 12 patients, 10 boys and two girls, were studied. Median stool volume was 27.5 mL/kg/day (range 10.1-109.0).The median age at BMT was 11.1 yr (range 3.9-17.0 yr). All patients had negative stool electron microscopy for viruses and cultures for C. difficile on their first collection. Nine patients (75%) had two 24-h stool collections performed at a median of eight days apart (range 7-14 days). At the time of the first collection, six patients had ≥ stage 2 acute gut GVHD, and at second collection, four patients had ≥ stage 2 gut GVHD and four collections were of non-diarrheal stool (hence treatment response). Median AATC from all 21 collections was 19.0 mL/day (range 3.0-561.0), and levels >22 mL/day indicate the diagnosis of PLE. The four children initially suspected of GVHD but who had a negative biopsy completed a total of five collections with a median AATC of 5.0 mL/day (range 3.0-16.0) vs. a median of 33.5 for the remainder of the collections (range 3-561). Stage of gut GVHD correlated with elevated AATC and with stool volume. AATC > 22 mL/day showed a sensitivity of 70% and specificity of 82% for significant gut GVHD (≥ stage 2). Seven stool collections were taken at ≥ stage 3 gut GVHD; six of those seven patients were positive for PLE. Larger stool volumes were more predictive, and five collections with stool volumes >30 mL/kg/day were positive for PLE. We conclude that a significant positive correlation exists between the severity of PLE and the stage of gut GVHD (p < 0.04), particularly obvious in patients with stages 2-4 GVHD (p = 0.03). Despite the small number of patients recruited, this study emphasizes the need to consider PLE as a useful aspect of the clinical picture. We suggest that in order to see a response to therapy and therefore a decrease in AATC, clinicians should wait at least 2 wk from the initiation of therapy before repeating AATC test. In light of the significant morbidity and mortality associated with ≥ stage 2 gut GVHD, and as an important therapeutic decision for these patients, one may consider evaluating AATC if a biopsy is not an option.

Small Bowel Evaluation in Asymptomatic Fecal Immunochemical Test-Positive Patients with a Negative Colonoscopy: Is It Necessary?

Screening for colorectal cancer (CRC) and its precursors by fecal occult blood test (FOBT) is widely recommended and is being applied more than ever [1–3]. Although annual or biennial guaiac fecal occult blood test (gFOBT) screening has been proved to reduce the mortality of CRC [4], the gFOBT has been faulted for its low sensitivity [5, 6]. More recently, the fecal immunochemical test (FIT) has been introduced as an alternative to the gFOBT. The FIT is currently preferred over the gFOBT due to its higher sensitivity and improved detection rate for advanced neoplasia [5, 7–10]. Besides its diagnostic performance, the FIT has several advantages over the gFOBT including no need for dietary restriction, easier stool collection method, and automated analysis [11]. Furthermore, quantitative FIT allows for the adjustment of the cutoff value for an abnormal result based on population characteristics and available colonoscopy resources. Due to these characteristics, quantitative FIT is more favored as a screening tool than qualitative FIT [11]. The FIT selectively reacts with the globin moiety of human hemoglobin [12]. Because globin is rapidly degraded by proteases in the upper gastrointestinal (GI) tract, the FIT dose not detect small amounts of blood in the upper GI tract and selectively recognizes occult bleeding of colorectal origin [12]. With regard to small bowel lesions, although there is a possibility that some small bowel occult bleeding could be identified by FIT, no data are currently available regarding this issue. In the current issue of Digestive Diseases and Sciences, Chiba et al. [13] present the results of their prospective study on small bowel evaluation in asymptomatic FIT-positive subjects with a negative colonoscopy. In this, the first study to evaluate the small bowel with capsule endoscopy (CE) in asymptomatic FIT-positive patients with a negative colonoscopy, 53 asymptomatic patients with FIT-positivity and a negative total colonoscopy and esophagogastroduodenoscopy underwent CE. The CE findings were classified into three categories: P0, no abnormalities or findings without potential for bleeding; P1, findings with uncertain potential for bleeding; and P2, findings with high potential for bleeding. The cecal completion rate was 92.5%. There were no cases of P2, 19 cases of P1, and 34 cases of P0. Moreover, no abnormalities were identified in five patients who underwent additional diagnostic evaluations that were considered necessary based on the individual clinical results. No clinically significant small bowel lesions were found in the asymptomatic FIT-positive patients with negative bidirectional endoscopy. Although FIT has been widely accepted as a CRC screening tool, 40–60% of subjects with a positive FIT are found to have no lesions in their colon or rectum to explain their positive status [5, 14, 15]. How then do we explain the discrepancy between the results of FIT and colonoscopy? There are several possible explanations for this discrepancy. First, this may reflect true false-positive results of FIT for advanced neoplasia. Quantitative FIT results are subjected to predetermined cut-off values for fecal hemoglobin; this methodology could inevitably yield some true false positives. Additionally, medications that can increase the likelihood of GI bleeding may cause false-positive FIT J. J. Park Department of Internal Medicine, Kyung Hee University Hospital at Gangdong, Kyung Hee University, Seoul, Korea

Economic implications of three strategies for the control of taeniasis

To evaluate the cost-effectiveness of three strategies for the control of taeniasis in a community, in terms of cost per case treated. A study was conducted in South India to determine the prevalence of taeniasis by screening stool samples from 653 randomly chosen subjects, for coproantigens. The costs incurred in the project were used to estimate the cost per case screened and treated. A one-way sensitivity analysis was carried out for varying rates of taeniasis, different screening strategies and mass therapy. Further sensitivity analysis was carried out with different manpower and test costs. The rate of taeniasis as detected by ELISA for coproantigen was 3 per 1000 (2 of 653 samples). Our study showed that mass therapy without screening for taeniasis would be the most economical strategy in terms of cost per case treated if field workers are employed exclusively for either mass therapy or screening. For each strategy, costs per case treated are higher at low prevalence of taeniasis, with a sharp rise below 15%. In places that are endemic for taeniasis and neurocysticercosis, mass therapy or screening for taeniasis should be considered. Screening by stool microscopy is not cost-effective in terms of cost per case of taeniasis treated owing to its low sensitivity. Although the cost per case of taeniasis treated is high at low prevalence of taeniasis for all options, incorporating mass therapy into existing mass drug distribution programmes might prove to be the most cost-effective control strategy.

The Effect of Egg Embryonation on Field-Use of a Hookworm Benzimidazole-Sensitivity Egg Hatch Assay in Yunnan Province, People's Republic of China

BackgroundCurrent efforts to control human soil-transmitted helminths (STHs) involve the periodic mass administration of benzimidazole drugs to school aged children and other at- risk groups. Given that high levels of resistance to these drugs have developed in roundworms of livestock, there is a need to monitor drug efficacy in human STHs. The current study aimed to evaluate an in vitro egg hatch assay for measuring the sensitivity of human hookworms to benzimidazole drugs in an isolated field setting in southern Yunnan province, People's Republic of China.Methodology/Principal FindingsEgg hatch assays were performed with hookworm (Necator americanus) eggs extracted from 37 stool samples received from local school-aged children. The mean IC50 was 0.10 ug/ml thiabendazole (95% CIs: 0.09–0.12 ug/ml). Observation of the eggs immediately prior to assay set-up revealed that a small percentage had embryonated in some samples. Scoring of % embryonation of eggs prior to the assay allowed for corrections to be made to IC50, IC95 and IC99 values. Examination of the data with and without this correction revealed that the embryonation of a small number of eggs did not affect IC50 values, but did increase IC95 and IC99 values for some samples.Conclusions/SignificanceThis study has highlighted the impact of egg embryonation on the use of benzimidazole drug sensitivity assays for human hookworms in field settings. Given the greater flexibility required in human stool collection procedures compared to livestock studies, we suggest that embryonation of some eggs may be an unavoidable issue in some human studies. Hence, it needs to be measured and accounted for when analysing dose response data, particularly for generation of IC95 and IC99 values. The protocols used in this study and our suggested measures for accounting for egg embryonation should have widespread application in monitoring benzimidazole sensitivity at field sites worldwide.

Faecal calprotectin (FC) in secondary care: unnecessarily complex or definitely helpful?

Introduction Faecal calprotectin (FC) is a protein complex released from degraded neutrophils exuded through the gut wall into the lumen. Its levels are therefore likely to better reflect the presence and intensity of gut inflammation than our conventional inflammatory markers: C reactive protein (most commonly used by us), platelets, albumin, endoscopy, histopathology and imaging. FC values (mg/kg) suggest inflammatory status as 100: likely; >1000: definite. The factors limiting its routine use include need for spot stool collection, which many patients dislike and the time involved for manual assay, hence higher cost. Is the ‘help’ in decision making worth the effort and cost? Aim To test the utility of FC in the routine clinical setting of a gastroenterology unit in a UK DGH. Methods Retrospective study of consecutive new and follow up patients who had FC (PhiCal ELISA test) done in our clinics between 10/2007 and 2/2009 (n = 200). Patients were categorised into IBD-flare (relapse), IBD-active (persistent activity), IBD-remission and non-IBD (eg, IBS, abdominal pain, weight loss). The spot FC values are tabulated as median and range according to presence or absence of inflammation by conventional markers as above (≤ 1 test done within 2 weeks in majority). Results See table 1. Conclusion FC levels > 500 correlate well with flare and active IBD. Very low levels ( 7.8 in non-IBD patients (majority of new referrals) may indicate ongoing GI inflammation in a few and hence the need to investigate fully rather than assume functional GI disease as the FC levels are within the published “normal” range. Raised FC in IBD-remission may signify ongoing silent inflammation with potentially significant influence on long-term prognosis (an area to be explored). Discussion This retrospective pilot study in our unit suggests that the effort and cost of FC is exceeded by the help it offers. It is of definite help when levels are very high or very low. We need to assess systematically the disease correlation with moderate FC elevation to develop local normal values.

Portage parasitaire intestinal chez l’enfant scolarisé à Salé, Maroc

Intestinal parasitic infections are among the most widespread of human infections in developing countries, and children are the most vulnerable. The aim of this study was to determine the prevalence of protozoa and intestinal helminthes, as well as the risk factors of intestinal parasites in schoolchildren in Salé city, Morocco. This is a study of incidence and prevalence conducted prospectively over a period of five months in schoolchildren in Salé city. The collection of stool was performed over three days (j1, j3, j5). In addition, adhesive cellophane tape slide evaluation was performed on day 7 for all students included in this work. During the study period, we included 123 students. Seventy-six children (61.7%) were infected by intestinal parasites. The age group 12-14 years is by far the most affected. Protozoa were found in 57.7% (N = 71) of children examined. Amoebae family parasites were predominant. Helminths were present in 26% (N = 32) of the schoolchildren. Forty-five (36.6%) children were poly-parasitized. This work shows that the prevalence of intestinal parasitism is quite high among primary schoolchildren in Salé city. Several parasite species are found. This finding is explained by unhealthy living conditions and poor hygiene, predisposing to endemicity and perpetuation of the transmission. The impact on health is not negligible especially when compounded by malnutrition. The best way to fight this scourge is prevention and awareness.

High Alpha-1 Antitrypsin Clearance Predicts Severity of Gut Graft Versus Host Disease (GVHD) In Children

AbstractAbstract 1242The clinical evaluation and management of gut GVHD is a significant challenge in pediatric hematopoietic stem cell transplantation (HSCT). It is often difficult to obtain pathological evidence to confirm the GVHD diagnosis and/or determine response to treatment. The severity of the disease itself may not just be related to the associated classic symptoms. Our objective herein was to prospectively study the effect of gut GVHD on protein losing enteropathy (PLE) as measured by alpha-1 antitrypsin clearance (AATC) in stools. Thirteen patients who were diagnosed with gut GVHD by clinical criteria were recruited; 5 patients were excluded as 4 had gut GVHD ruled out by biopsy and 1 was unable to complete study due to stool collection issues. Therefore, 8 patients; 6 males and 2 females, were studied. The median age was 9.5 years (range 6–17). Diagnoses included ALL (4), AML (2), Lymphoma (1) and Adrenoleukodystrophy (1). Donor types were; 7 unrelated (BM n=4 and cord n=3) one matched related BM donor. All patients received cyclosporine for GVHD prophylaxis, in addition 4 patients also received methotrexate and 3 others received prednisone as the second agent. All patients had negative stool EM for viruses and cultures for C.difficile on their first collection. Two 24 hour stool collections were taken from each patient at a mean of 8.5d (range 7–13d) apart. Patients' gut GVHD staging is summarized in Table 1.Table 1:Summary of Stage gut GVHD and PLEPatientsAATC Median(range)normal = <22Stool outputml/kg/d Median(range)Stage of gutGVHD (n=)# with PLECollection #1831 (3-339)28 (10-109)Stg 1 (2)4/8Stg 2 (3)Stg 3 (1)Stg 4 (2)Collection #2856 (8-561)19 (0-85)Stg 1 (0)5/8Stg 2 (0)Stg 3 (3)Stg 4 (1)At the time of 1st collection, 6 patients had ≥ stage II gut GVHD and at 2nd collection 4 patients had ≥stage II gut GVHD and 4 collections were of non-diarrheal stool. A total of 7 stool collections were taken at a diagnosis of ≥stage III gut GVHD. Mean alpha-1 antitrypsin clearance (AATC) from all 16 collections was 143 mls/day (range 3–561), levels >22 mls/day indicate the diagnosis of protein-losing enteropathy (PLE). Nine of the collections (56%) showed PLE with a mean AATC of 247mls/day (range 31–561). Six out of the 7 samples from patients with ≥stage III gut GVHD were positive for PLE. Five collections with stool volumes >30 ml/kg/day were positive for PLE. Stool volumes were significantly higher on second collection (Wilcoxon signed ranks test, p = 0.003) consistent with the second stool collections being significantly more likely to have an elevated AATC, therefore more severe PLE over time (p<0.001). We conclude that a highly significant positive correlation exists between the severity of PLE and the stage of gut GVHD, particularly obvious in patients with stage 3–4 GVHD (ANOVA, p=0.015). See Table 2.Table 2:Stage of gut GVHD and AATCStage ofGVHDNumber ofcollectionsMeanAATCStd.Deviation0426.0020.801217.0019.802384.67136.2934171.50176.2143406.33134.32When patients were grouped as stage 0–2 GVHD vs. stage 3–4 GVHD, those with stage 3–4 GVHD had significantly higher AATC values (p =0.02). Despite the small number of patients recruited, this study emphasizes the need to consider PLE as a useful aspect of the clinical picture. We suggest that in order to see a response to therapy and therefore a decrease in AATC, clinicians should not repeat stool collections before 2 weeks from the initiation of therapy. In light of the significant morbidity and mortality associated with grade 3 and 4 gut GVHD, and as an important therapeutic decision for these patients, one may consider escalating GVHD therapy if a patient's AATC is rising. Disclosures:No relevant conflicts of interest to declare.

Optimizing the Use of Deferasirox: Evidence of Synergy When Combined with Deferoxamine

AbstractAbstract 5163 Introduction:Deferasirox (Exjade, ICL670) is an orally effective iron chelating agent approved for use in patients 2 years of age and older with transfusional iron overload. While it is effective as a single agent, there are patients who do not attain net negative iron balance despite being at the upper limit of approved dosing (40 mg/kg/day). Deferiprone (Ferriprox, L1) is another orally effective iron chelator. Through a series of metabolic iron balance studies we were able to demonstrate that various regimens involving the combined use of deferiprone and deferoxamine (Desferal, DFO) were capable of placing all patients into net negative iron balance with the potential to adjust dosing schedules and the ratio of drugs to maximize effectiveness while minimizing toxicity. A variety of such regimens are now in widespread clinical use. We have taken the same approach in order to optimize the use of deferasirox. Methods:Six patients with thalassemia major were enrolled in a 34-day metabolic iron balance study wherein deferasirox and deferoxamine were evaluated alone and in combination, each patient serving as his/her own control. Deferoxamine (40 mg/kg) was administered on days 5 – 10 as an 8-hour subcutaneous infusion during the night. On days 15 – 20, deferasirox (30 mg/kg) was given orally, 30 minutes prior to breakfast. Both drugs were given on days 25 – 30, the same doses and dosing schedules being employed. Non drug days allowed for washout of stool iron induced by the previous treatment. The patients consumed a fixed low-iron diet consisting of four individualized meal plans. Daily collections of urine and stool were made and their iron content determined by atomic absorption, a correction being made for all uneaten food. Results:As in previous studies, there was significant patient to patient variability in terms of the amount of drug-induced iron excretion. Combination therapy placed all patients into iron balance exceeding 200% (206% - 270%, mean 251%). The combination was synergistic in two patients (35% and 57%), additive in three patients, and less than additive in one patient. Where iron excretion was more than additive, all of the excess appeared in the urine (a 2.1- and 3.4-fold increase). Deferasirox proved to be less effective than deferoxamine in all six patients (relative iron excretion: 23% - 59%, mean 42%), stool iron excretion in response to the respective drugs being 94% -100% (mean 98%) and 49% - 74% (mean 59%). Net negative iron balance was achieved in 2/6 patients when on deferasirox (iron balance 28% - 129%, mean 72%) and 6/6 patients when infusing deferoxamine (iron balance 125% - 219%, mean 167%). Discussion:These results suggest that chelation therapy can be tailored to the individual needs of each patient, selectively removing iron from different pools while minimizing any side effects. Deferasirox appears to shuttle iron to deferoxamine for excretion in the urine, not unlike the situation when deferiprone and deferoxamine are combined, although the source of the iron may be somewhat different. It is hoped that these results will provide patients with further options to optimize their chelation regimens. Disclosures:Grady:Novartis Pharmaceuticals: Research Funding. Off Label Use: Deferasirox and Deferoxamine are both iron chelating agents. Their use in combination is not indicated on their labeling. Galanello:Novartis Pharmaceuticals: Speakers Bureau. Paley:Novartis Pharmaceuticals: Employment. Giardina:Novartis Pharmaceuticals: Research Funding.

The association of bile acid excretion and atherosclerotic coronary artery disease

Excess cholesterol is usually eliminated from the body by conversion to bile acids excreted in feces as bile salts. The excretion of large amounts of bile protects against atherosclerosis, while diminished excretion may lead to coronary artery disease (CAD). To investigate a relationship between CAD and bile acid excretion. Bile acid excretion was compared between 36 patients with proven CAD and 37 CAD-free individuals (controls). The groups were comparable for demographics and selected risk factors. All subjects received a 4-day standard diet that included ∼500 mg of cholesterol. Fecal bile acids from 24-hour stool collections were measured by gas liquid chromatography. CAD patients excreted lower amounts of total bile acids (358 ± 156 mg) than controls (617 ± 293 mg; p < 0.01) and less deoxycholic acid (188.29 ± 98.12 mg versus 325.96 ± 198.57 mg; p < 0.0001) and less lithocholic acid (115.43 ± 71.89 mg versus 197.27 ± 126.87 mg; p < 0.01). Advanced age, male gender, left ventricular ejection fraction and total bile acid levels were significant independent factors that predicted CAD (p < 0.05). Mortality, CAD and cerebrovascular accident development rates were significantly lower for the controls at the 13-year follow up. CAD patients have significantly decreased bile acid excretion levels than non-CAD patients. An impaired ability to excrete cholesterol may be an additional risk factor for CAD development.

CommensalEscherichia coliIsolate Resistant to Eight Classes of Antimicrobial Agents in the United States

To increase understanding of community-acquired resistance, stool samples from 477 nonhospitalized persons in Maryland and Michigan, from 2004 to 2008, were screened for ceftriaxone resistance. Seven (1.5%) yielded ceftriaxone-resistant Escherichia coli; one isolate was resistant to all eight antimicrobial classes routinely tested: aminoglycosides, β-lactam/β-lactamase inhibitor combinations, cephems, penicillins, folate pathway inhibitors, phenicols, quinolones, and tetracyclines. The extensively resistant isolate was from a 50-year-old woman who denied antimicrobial use, hospitalization, or international travel within 6 months. Meat (beef, chicken, and pork) and eggs were consumed within 1 month before stool collection. Further studies are warranted to understand potential sources, including the food supply, of resistant E. coli.

Comparison of monoclonal antibody-based stool antigen tests to determine the results of Helicobacter pylori eradication therapy

Objective. Stool antigen tests using monoclonal antibody are used to test the results of eradication therapy of Helicobacter pylori. A newly developed test using multiple monoclonal antibodies is considered to have higher sensitivity. The aim of this study was to examine whether monoclonal antibody-based stool antigen tests are equally applicable to determine the results of eradication therapy. Materials and methods. Stool specimens obtained from patients infected with H. pylori were diluted by human stool and tested by both Testmate pylori antigen enzyme immunoassay (TPAg EIA) and Premier Platinum HpSA PLUS (HpSA ELISA II). A total of 239 patients infected with H. pylori received eradication therapy and 5–8 weeks after finishing the treatment, stool samples were tested by TPAg EIA and HpSA ELISA II. On the same day of stool collection, all the patients received 13C-urea breath test (UBT). Results. After 5× dilution, optical density (OD) values of TPAg EIA were significantly reduced and three out of four stool specimens were tested negative after 10× dilution. By contrast, three specimens were tested positive even after 100× dilution by HpSA ELISA II. In the determination of eradication therapy, accordance between the two tests was 95.8%. Among 199 patients who tested negative by both stool antigen tests, 10 patients were positive by UBT. Overall accordance of TPAg EIA and HPSA ELISA II to UBT was 91.2% and 95.4%, respectively (NS). Conclusions. Although reduction of OD values was seen in TPAg EIA, it did not seem to cause false negative results in stool samples after eradication therapy. Both TPAg EIA and HpSA ELISA II were equally useful to determine the results of eradication therapy comparing with UBT.

A case of Cronkhite–Canada syndrome presenting with adenomatous and inflammatory colon polyps

A 72-year-old man was referred for evaluation of dysgeusia, diarrhea and anorexia. 3 months prior he began to experience taste changes, a decline in appetite and 3-7 loose, non-bloody stools per day. Nausea and lower abdominal cramping subsequently developed and he lost 22.68 kg in weight. His past medical history included atrial fibrillation treated with anticoagulation and digoxin. In the past, he had experienced markedly increased levels of triglycerides and was being treated for this condition with a lipid-lowering agent. There was no family history of colorectal neoplasia or IBD. He was a non-smoker and did not drink alcoholic beverages. Medical history, physical examination, laboratory evaluation (including 72 h stool collection), upper endoscopy, colonoscopy and histologic analysis of biopsy samples. Cronkhite-Canada syndrome. Prednisone (40 mg orally once daily, eventually tapered to 10 mg orally once daily), a histamine-2-receptor blocker and oral micronutrient supplementation (iron, vitamins A, E and D and a multivitamin). Removal of all visible polyps from the anal verge to 25 cm endoscopically by snare polypectomy or with hot biopsy forceps, followed by subtotal colectomy with end-to-side ileorectostomy.

Does the handling time of unrefrigerated human fecal specimens impact the detection of Clostridium difficile toxins in a hospital setting?

The stability of Clostridium difficile toxins is an important factor in determining the accuracy of the enzyme immunoassay (EIA). The Centers for Disease Control has stated that C. difficile toxins may become undetectable in unrefrigerated stool specimens within 2h after collection. The purpose of our study was to determine how the unrefrigerated handling time of human fecal specimens affects the results of C. difficile infection (CDI) testing. A retrospective review of CDI testing with Premier™ Toxins A and B kit was conducted in northern New Jersey, USA. Stool collection times and receiving times were recorded for each specimen. The unrefrigerated handling time was calculated for each. A total of 1126 fecal specimens were submitted. We excluded 72 fecal specimens due to incomplete documentation. We included 1054 fecal specimens collected from 636 hospitalized patients. A total of 132 out of 1054 specimens (12.5%) tested positive for C. difficile toxins. Nine hundred and fifty-four specimens were unrefrigerated for 13h or less, of which 127 (13.3%) tested positive. Five (5%) of the 100 specimens that were unrefrigerated for more than 13h tested positive (p = 0.02). C. difficile toxins can still be detected up to 13h after collection in unrefrigerated human fecal specimens. However, fecal specimens should be processed according to the current recommendations to ensure the reliability of EIA testing until the results of our study are confirmed with prospective studies.

Cyclodextrin overcomes the transport defect in nearly every organ of NPC1 mice leading to excretion of sequestered cholesterol as bile acid

A mutation in NPC1 leads to sequestration of unesterified cholesterol in the late endosomal/lysosomal compartment of every cell culminating in the development of pulmonary, hepatic, and neurodegenerative disease. Acute administration of 2-hydroxypropyl-beta-cyclodextrin (CYCLO) rapidly overcomes this transport defect in both the 7-day-old pup and 49-day-old mature npc1(-/-) mouse, even though this compound is cleared from the body and plasma six times faster in the mature mouse than in the neonatal animal. The liberated cholesterol flows into the cytosolic ester pool, suppresses sterol synthesis, down-regulates SREBP2 and its target genes, and reduces expression of macrophage-associated inflammatory genes. These effects are seen in the liver and brain, as well as in peripheral organs like the spleen and kidney. Only the lung appears to be resistant to these effects. Forty-eight h after CYCLO administration to the 49-day-old animals, fecal acidic, but not neutral, sterol output increases, whole-animal cholesterol burden is reduced, and the hepatic and neurological inflammation is ameliorated. However, lifespan is extended only when the CYCLO is administered to the 7-day-old animals. These studies demonstrate that CYCLO administration acutely reverses the cholesterol transport defect seen in the NPC1 mouse at any age, and this reversal allows the sequestered sterol to be excreted from the body as bile acid.

Fecal Occult Blood Test in Patients on Low-Dose Aspirin, Warfarin, Clopidogrel, or Non-steroidal Anti-inflammatory Drugs

To determine the effect of anticoagulants and antiplatelet medications on the positive-predictive-value of fecal occult blood test (FOBT). All patients who underwent a colonoscopy at our institution from 1995 to 2006 for a positive FOBT were identified. Medical records were searched, and patients were stratified into five groups selected a priori: low-dose aspirin, NSAIDs, warfarin, clopidogrel, or controls. The positive-predictive-value of FOBT for advanced colonic neoplasia was computed for each group. During the study period, 1,126 patients underwent colonoscopy for a positive FOBT and met entry criteria. The average age of study participants was 69 years and most were men. The positive-predictive-value of FOBT for advanced colon neoplasia was significantly higher in the control group (30.5%) when compared to those on low-dose aspirin (20.5%; p = 0.003), NSAIDs (19.7%; p = 0.003), clopidogrel (7.3%; p = 0.002), or warfarin (20%; p = 0.05). The positive-predictive-value of FOBT was significantly lower for those on clopidogrel than those on low-dose aspirin (p = 0.04) and NSAIDs (p = 0.05), but not warfarin (p = 0.08). The positive-predictive-value for FOBT was similar for those on aspirin, NSAIDs, and warfarin. There was a linear trend between the number of number of positive FOBT cards and prevalence of advanced colon neoplasia (p = 0.01). Anticoagulants and antiplatelet medications lower the positive-predictive-value of FOBT for advance colonic neoplasia and should be stopped if clinically feasible prior to stool collection.