Person: Leffler, Daniel
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Publication Clostridium difficile outbreaks: Prevention and treatment strategies
(Dove Medical Press, 2012) Martinez, Fernando J; Leffler, Daniel; Kelly, CiaranThe incidence and severity of Clostridium difficile infection (CDI) have increased dramatically over the past decade. Its treatment, however, has largely remained the same with the exception of oral vancomycin use as a first-line agent in severe disease. From 1999 to 2004, 20,642 deaths were attributed to CDI in the United States, almost 7 times the rate of all other intestinal infections combined. Worldwide, several major CDI outbreaks have occurred, and many of these were associated with the NAP1 strain. This ‘epidemic’ strain has contributed to the rising incidence and mortality of CDI. The purpose of this article is to review the current management, treatment, infection control, and prevention strategies that are needed to combat this increasingly morbid disease.
Publication A Randomized, Double-Blind Study of Larazotide Acetate to Prevent the Activation of Celiac Disease During Gluten Challenge
(Nature Publishing Group, 2012) Leffler, Daniel; Kelly, Ciaran; Abdallah, H Z; Colatrella, A M; Harris, L A; Leon, F; Arterburn, L A; Paterson, B M; Lan, Z H; Murray, J AOBJECTIVES: In patients with celiac disease, enteropathy is caused by the entry of gluten peptides into the lamina propria of the intestine, in which their immunogenicity is potentiated by tissue transglutaminase (tTG) and T-helper type 1–mediated immune responses are triggered. Tight junction disassembly and paracellular permeability are believed to have an important role in the transport of gluten peptides to the lamina propria. Larazotide acetate is a tight-junction regulator peptide that, in vitro, prevents the opening of intestinal epithelial tight junctions. The aim of this study was to evaluate the efficacy and tolerability of larazotide acetate in protecting against gluten-induced intestinal permeability and gastrointestinal symptom severity in patients with celiac disease. METHODS: In this dose-ranging, placebo-controlled study, 86 patients with celiac disease controlled through diet were randomly assigned to larazotide acetate (0.25, 1, 4, or 8 mg) or placebo three times per day with or without gluten challenge (2.4 g/day) for 14 days. The primary efficacy outcome was the urinary lactulose/mannitol (LAMA) fractional excretion ratio. Secondary endpoints included gastrointestinal symptom severity, quality-of-life measures, and antibodies to tTG. RESULTS: LAMA measurements were highly variable in the outpatient setting. The increase in LAMA ratio associated with the gluten challenge was not statistically significantly greater than the increase in the gluten-free control. Among patients receiving the gluten challenge, the difference in the LAMA ratios for the larazotide acetate and placebo groups was not statistically significant. However, larazotide acetate appeared to limit gluten-induced worsening of gastrointestinal symptom severity as measured by the Gastrointestinal Symptom Rating Scale at some lower doses but not at the higher dose. Symptoms worsened significantly in the gluten challenge–placebo arm compared with the placebo–placebo arm, suggesting that 2.4 g of gluten per day is sufficient to induce reproducible gluten toxicity. Larazotide acetate was generally well tolerated. No serious adverse events were observed. The most common adverse events were headache and urinary tract infection. CONCLUSIONS: LAMA variability in the outpatient setting precluded accurate assessment of the effect of larazotide acetate on intestinal permeability. However, some lower doses of larazotide acetate appeared to prevent the increase in gastrointestinal symptom severity induced by gluten challenge.
Publication Acid Suppression Therapy Does Not Predispose to Clostridium difficile Infection: The Case of the Potential Bias
(Public Library of Science, 2014) Novack, Lena; Kogan, Slava; Gimpelevich, Larisa; Howell, Michael; Borer, Abraham; Kelly, Ciaran; Leffler, Daniel; Novack, VictorObjective: An adverse effect of acid-suppression medications on the occurrence of Clostridium difficile infection (CDI) has been a common finding of many, but not all studies. We hypothesized that association between acid-suppression medications and CDI is due to the residual confounding in comparison between patients with infection to those without, predominantly from non-tested and less sick subjects. We aimed to evaluate the effect of acid suppression therapy on incidence of CDI by comparing patients with CDI to two control groups: not tested patients and patients suspected of having CDI, but with a negative test. Methods: We conducted a case-control study of adult patients hospitalized in internal medicine department of tertiary teaching hospital between 2005–2010 for at least three days. Controls from each of two groups (negative for CDI and non-tested) were individually matched (1∶1) to cases by primary diagnosis, Charlson comorbidity index, year of hospitalization and gender. Primary outcomes were diagnoses of International Classification of Diseases (ICD-9)–coded CDI occurring 72 hours or more after admission. Results: Patients with CDI were similar to controls with a negative test, while controls without CDI testing had lower clinical severity. In multivariable analysis, treatment by acid suppression medications was associated with CDI compared to those who were not tested (OR = 1.88, p-value = 0.032). Conversely, use of acid suppression medications in those who tested negative for the infection was not associated with CDI risk as compared to the cases (OR = 0.66; p = 0.059). Conclusions: These findings suggest that the reported epidemiologic associations between use of acid suppression medications and CDI risk may be spurious. The control group choice has an important impact on the results. Clinical differences between the patients with CDI and those not tested and not suspected of having the infection may explain the different conclusions regarding the acid suppression effect on CDI risk.
Publication Diagnosis and management of adult coeliac disease: guidelines from the British Society of Gastroenterology
(BMJ Publishing Group, 2014) Ludvigsson, Jonas F; Bai, Julio C; Biagi, Federico; Card, Timothy R; Ciacci, Carolina; Ciclitira, Paul J; Green, Peter H R; Hadjivassiliou, Marios; Holdoway, Anne; van Heel, David A; Kaukinen, Katri; Leffler, Daniel; Leonard, Jonathan N; Lundin, Knut E A; McGough, Norma; Davidson, Mike; Murray, Joseph A; Swift, Gillian L; Walker, Marjorie M; Zingone, Fabiana; Sanders, David SA multidisciplinary panel of 18 physicians and 3 non-physicians from eight countries (Sweden, UK, Argentina, Australia, Italy, Finland, Norway and the USA) reviewed the literature on diagnosis and management of adult coeliac disease (CD). This paper presents the recommendations of the British Society of Gastroenterology. Areas of controversies were explored through phone meetings and web surveys. Nine working groups examined the following areas of CD diagnosis and management: classification of CD; genetics and immunology; diagnostics; serology and endoscopy; follow-up; gluten-free diet; refractory CD and malignancies; quality of life; novel treatments; patient support; and screening for CD.
Publication Attitudes to Mesalamine Questionnaire: A Novel Tool to Predict Mesalamine Nonadherence in Patients with IBD
(Springer Nature, 2014) Moss, Alan; Lillis, Yvonne; Edwards George, Jessica B.; Choudhry, Niteesh; Berg, Anders; Cheifetz, Adam; Horowitz, Gary Leigh; Leffler, DanielOBJECTIVES: Poor adherence to mesalamine is common and driven by a combination of lifestyle and behavioral factors, as well as health beliefs. We sought to develop a valid tool to identify barriers to patient adherence and predict those at risk for future nonadherence. METHODS: A 10-item survey was developed from patient-reported barriers to adherence. The survey was administered to 106 patients with ulcerative colitis who were prescribed mesalamine, and correlated with prospectively collected 12-month pharmacy refills (medication possession ratio (MPR)), urine levels of salicylates, and self-reported adherence (Morisky Medication Adherence Scale (MMAS)-8). RESULTS: From the initial 10-item survey, 8 items correlated highly with the MMAS-8 score at enrollment. Computer-generated randomization produced a derivation cohort of 60 subjects and a validation cohort of 46 subjects to assess the survey items in their ability to predict future adherence. Two items from the patient survey correlated with objective measures of long-term adherence: their belief in the importance of maintenance mesalamine even when in remission and their concerns about side effects. The additive score based on these two items correlated with 12-month MPR in both the derivation and validation cohorts (P<0.05). Scores on these two items were associated with a higher risk of being nonadherent over the subsequent 12 months (relative risk (RR) =2.2, 95% confidence interval=1.5–3.5, P=0.04). The area under the curve for the performance of this 2-item tool was greater than that of the 10-item MMAS-8 score for predicting MPR scores over 12 months (area under the curve 0.7 vs. 0.5). CONCLUSIONS: Patients’ beliefs about the need for maintenance mesalamine and their concerns about side effects influence their adherence to mesalamine over time. These concerns could easily be raised in practice to identify patients at risk of nonadherence (Clinical Trial number NCT01349504).
Publication Wheat amylase trypsin inhibitors drive intestinal inflammation via activation of toll-like receptor 4
(The Rockefeller University Press, 2012) Junker, Yvonne; Zeissig, Sebastian; Kim, Seong-Jun; Barisani, Donatella; Wieser, Herbert; Leffler, Daniel; Zevallos, Victor; Libermann, Towia; Dillon, Simon; Freitag, Tobias L.; Kelly, Ciaran; Schuppan, DetlefIngestion of wheat, barley, or rye triggers small intestinal inflammation in patients with celiac disease. Specifically, the storage proteins of these cereals (gluten) elicit an adaptive Th1-mediated immune response in individuals carrying HLA-DQ2 or HLA-DQ8 as major genetic predisposition. This well-defined role of adaptive immunity contrasts with an ill-defined component of innate immunity in celiac disease. We identify the α-amylase/trypsin inhibitors (ATIs) CM3 and 0.19, pest resistance molecules in wheat, as strong activators of innate immune responses in monocytes, macrophages, and dendritic cells. ATIs engage the TLR4–MD2–CD14 complex and lead to up-regulation of maturation markers and elicit release of proinflammatory cytokines in cells from celiac and nonceliac patients and in celiac patients’ biopsies. Mice deficient in TLR4 or TLR4 signaling are protected from intestinal and systemic immune responses upon oral challenge with ATIs. These findings define cereal ATIs as novel contributors to celiac disease. Moreover, ATIs may fuel inflammation and immune reactions in other intestinal and nonintestinal immune disorders.
Publication An open-access endoscopy screen correctly and safely identifies patients for conscious sedation
(Oxford University Press, 2016) Kothari, Darshan; Feuerstein, Joseph; Moss, Laureen; D’Souza, Julie; Montanaro, Kerri; Leffler, Daniel; Sheth, SunilBackground and aims: Open-access scheduling is highly utilized for facilitating generally low-risk endoscopies. Preprocedural screening addresses sedation requirements; however, procedural safety may be compromised if screening is inaccurate. We sought to determine the reliability of our open-access scheduling system for appropriate use of conscious sedation. Methods: We prospectively and consecutively enrolled outpatient procedures booked at an academic center by open-access using screening after in-office gastroenterology (GI) consultation. We collected the cases inappropriately booked for conscious sedation and compared the characteristics for significant differences. Results: A total of 8063 outpatients were scheduled for procedures with conscious sedation, and 5959 were booked with open-access. Only 78 patients (0.97%, 78/8063) were identified as subsequently needing anesthesiologist-assisted sedation; 44 (56.4%, 44/78) were booked through open-access, of which chronic opioid (47.7%, 21/44) or benzodiazepine use (34.1%, 15/44) were the most common reasons for needing anesthesiologist-assisted sedation. Patients on chronic benzodiazepines required more midazolam than those not on chronic benzodiazepines (P = .03) of those patients who underwent conscious sedation. Similarly, patients with chronic opioid use required more fentanyl than those without chronic opioid use (P = .04). Advanced liver disease and alcohol use were common reasons for patients being booked after in-office consultation and were significantly higher than those booked with open-access (both P < .01). Conclusions: We observed that the majority of patients can be triaged for conscious sedation using a multi-tiered screening process. Importantly, few patients (<1.0%) were inappropriately booked for conscious sedation. The most common reasons for considering anesthesiologist-assisted sedation were chronic opioid, benzodiazepine and/or alcohol use and advanced liver disease. This suggests that these entities could be included in screening processes for open-access scheduling.
Publication Prospective randomized controlled study on the effects of Saccharomyces boulardii CNCM I-745 and amoxicillin-clavulanate or the combination on the gut microbiota of healthy volunteers
(Taylor & Francis, 2017) Kabbani, Toufic A.; Pallav, Kumar; Dowd, Scot E.; Villafuerte-Galvez, Javier; Vanga, Rohini R.; Castillo, Natalia E.; Hansen, Joshua; Dennis, Melinda; Leffler, Daniel; Kelly, CiaranABSTRACT Probiotics are believed to be beneficial in maintaining a healthy gut microbiota whereas antibiotics are known to induce dysbiosis. This study aimed to examine the effects of the probiotic Saccharomyces boulardii CNCM I-745 (SB), the antibiotic Amoxicillin-Clavulanate (AC) and the combination on the microbiota and symptoms of healthy humans. Healthy subjects were randomized to one of 4 study groups: SB for 14 days, AC for 7 days, SB plus AC, Control (no treatment). Participants gave stool samples and completed gastro-intestinal symptom questionnaires. Microbiota changes in stool specimens were analyzed using 16s rRNA gene pyrosequencing (bTEFAP). Only one subject withdrew prematurely due to adverse events. Subjects treated by S boulardii + AC had fewer adverse events and tolerated the study regimen better than those receiving the AC alone. Control subjects had a stable microbiota throughout the study period. Significant microbiota changes were noted in the AC alone group during antibiotic treatment. AC associated changes included reduced prevalence of the genus Roseburia and increases in Escherichia, Parabacteroides, and Enterobacter. Microbiota alterations reverted toward baseline, but were not yet completely restored 2 weeks after antibiotherapy. No significant shifts in bacterial genera were noted in the SB alone group. Adding SB to AC led to less pronounced microbiota shifts including less overgrowth of Escherichia and to a reduction in antibiotic-associated diarrhea scores. Antibiotic treatment is associated with marked microbiota changes with both reductions and increases in different genera. S. boulardii treatment can mitigate some antibiotic-induced microbiota changes (dysbiosis) and can also reduce antibiotic-associated diarrhea.
Publication Recent Advances in Celiac Disease from TTG to Gluten in Pee
(Nature Publishing Group, 2015) Silvester, J A; Leffler, DanielPublication A Multi-Center Prospective Derivation and Validation of a Clinical Prediction Tool for Severe Clostridium difficile Infection
(Public Library of Science, 2015) Na, Xi; Martin, Alan J.; Sethi, Saurabh; Kyne, Lorraine; Garey, Kevin W.; Flores, Sarah W.; Hu, Mary; Shah, Dhara N.; Shields, Kelsey; Leffler, Daniel; Kelly, CiaranBackground and Aims Prediction of severe clinical outcomes in Clostridium difficile infection (CDI) is important to inform management decisions for optimum patient care. Currently, treatment recommendations for CDI vary based on disease severity but validated methods to predict severe disease are lacking. The aim of the study was to derive and validate a clinical prediction tool for severe outcomes in CDI. Methods: A cohort totaling 638 patients with CDI was prospectively studied at three tertiary care clinical sites (Boston, Dublin and Houston). The clinical prediction rule (CPR) was developed by multivariate logistic regression analysis using the Boston cohort and the performance of this model was then evaluated in the combined Houston and Dublin cohorts. Results: The CPR included the following three binary variables: age ≥ 65 years, peak serum creatinine ≥2 mg/dL and peak peripheral blood leukocyte count of ≥20,000 cells/μL. The Clostridium difficile severity score (CDSS) correctly classified 76.5% (95% CI: 70.87-81.31) and 72.5% (95% CI: 67.52-76.91) of patients in the derivation and validation cohorts, respectively. In the validation cohort, CDSS scores of 0, 1, 2 or 3 were associated with severe clinical outcomes of CDI in 4.7%, 13.8%, 33.3% and 40.0% of cases respectively. Conclusions: We prospectively derived and validated a clinical prediction rule for severe CDI that is simple, reliable and accurate and can be used to identify high-risk patients most likely to benefit from measures to prevent complications of CDI.