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Crohn Disease: HELP
Articles by Ramon J. Sanchez
Based on 5 articles published since 2010
(Why 5 articles?)
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Between 2010 and 2020, R. Sanchez wrote the following 5 articles about Crohn Disease.
 
+ Citations + Abstracts
1 Review Pediatric Small Bowel Crohn Disease: Correlation of US and MR Enterography. 2015

Dillman, Jonathan R / Smith, Ethan A / Sanchez, Ramon J / DiPietro, Michael A / DeMatos-Maillard, Vera / Strouse, Peter J / Darge, Kassa. ·From the Section of Pediatric Radiology, Department of Radiology (J.R.D., E.A.S., R.J.S., M.A.D., P.J.S.), and Division of Pediatric Gastroenterology, Department of Pediatrics and Communicable Diseases (V.D.M.), C.S. Mott Children's Hospital, University of Michigan Health System, 1540 E Hospital Dr, Ann Arbor, MI 48109 · and Department of Radiology, Children's Hospital of Philadelphia, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pa (K.D.). ·Radiographics · Pubmed #25839736.

ABSTRACT: Small bowel Crohn disease is commonly diagnosed during the pediatric period, and recent investigations show that its incidence is increasing in this age group. Diagnosis and follow-up of this condition are commonly based on a combination of patient history and physical examination, disease activity surveys, laboratory assessment, and endoscopy with biopsy, but imaging also plays a central role. Ultrasonography (US) is an underutilized well-tolerated imaging modality for screening and follow-up of small bowel Crohn disease in children and adolescents. US has numerous advantages over computed tomographic (CT) enterography and magnetic resonance (MR) enterography, including low cost and no required use of oral or intravenous contrast material. US also has the potential to provide images with higher spatial resolution than those obtained at CT enterography and MR enterography, allows faster examination than does MR enterography, does not involve ionizing radiation, and does not require sedation or general anesthesia. US accurately depicts small bowel and mesenteric changes related to pediatric Crohn disease, and US findings show a high correlation with MR imaging findings in this patient population.

2 Article Defining the ultrasound longitudinal natural history of newly diagnosed pediatric small bowel Crohn disease treated with infliximab and infliximab-azathioprine combination therapy. 2017

Dillman, Jonathan R / Dehkordy, Soudabeh Fazeli / Smith, Ethan A / DiPietro, Michael A / Sanchez, Ramon / DeMatos-Maillard, Vera / Adler, Jeremy / Zhang, Bin / Trout, Andrew T. ·Department of Radiology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave., ML5031, Cincinnati, OH, 45229-3039, USA. jonathan.dillman@cchmc.org. · Department of Radiology, Section of Pediatric Radiology, C. S. Mott Children's Hospital, University of Michigan Health System, Ann Arbor, MI, USA. · Department of Pediatrics, Division of Gastroenterology, C. S. Mott Children's Hospital, University of Michigan Health System, Ann Arbor, MI, USA. · Division of Biostatistics and Epidemiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA. · Department of Radiology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave., ML5031, Cincinnati, OH, 45229-3039, USA. ·Pediatr Radiol · Pubmed #28421251.

ABSTRACT: BACKGROUND: Little is known about changes in the imaging appearances of the bowel and mesentery over time in either pediatric or adult patients with newly diagnosed small bowel Crohn disease treated with anti-tumor necrosis factor-alpha (anti-TNF-α) therapy. OBJECTIVE: To define how bowel ultrasound findings change over time and correlate with laboratory inflammatory markers in children who have been newly diagnosed with pediatric small bowel Crohn disease and treated with infliximab. MATERIALS AND METHODS: We included 28 pediatric patients treated with infliximab for newly diagnosed ileal Crohn disease who underwent bowel sonography prior to medical therapy and at approximately 2 weeks, 1 month, 3 months and 6 months after treatment initiation; these patients also had laboratory testing at baseline, 1 month and 6 months. We used linear mixed models to compare mean results between visits and evaluate whether ultrasound measurements changed over time. We used Spearman rank correlation to assess bivariate relationships. RESULTS: Mean subject age was 15.3±2.2 years; 11 subjects were girls (39%). We observed decreases in mean length of disease involvement (12.0±5.4 vs. 9.1±5.3 cm, P=0.02), maximum bowel wall thickness (5.6±1.8 vs. 4.7±1.7 mm, P=0.02), bowel wall color Doppler signal (1.7±0.9 vs. 1.2±0.8, P=0.002) and mesenteric color Doppler signal (1.1±0.9 vs. 0.6±0.6, P=0.005) at approximately 2 weeks following the initiation of infliximab compared to baseline. All laboratory inflammatory markers decreased at 1 month (P-values<0.0001). There was strong correlation between bowel wall color Doppler signal and fecal calprotectin (ρ=0.710; P<0.0001). Linear mixed models confirmed that maximum bowel wall thickness (P=0.04), length of disease involvement (P=0.0002) and bowel wall color Doppler signal (P<0.0001) change over time in response to infliximab, when adjusted for age, sex, azathioprine therapy, scanning radiologist and baseline short pediatric Crohn's disease activity index score. CONCLUSION: The ultrasound appearance of the bowel changes as early as 2 weeks after the initiation of infliximab therapy. There is strong correlation between bowel wall color Doppler signal and fecal calprotectin.

3 Article DWI in Pediatric Small-Bowel Crohn Disease: Are Apparent Diffusion Coefficients Surrogates for Disease Activity in Patients Receiving Infliximab Therapy? 2016

Dillman, Jonathan R / Smith, Ethan A / Sanchez, Ramon / Adler, Jeremy / Fazeli, Soudabeh / Zhang, Bin / Davenport, Matthew S. ·1 Department of Radiology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229-3039. · 2 Section of Pediatric Radiology, Department of Radiology, C. S. Mott Children's Hospital, University of Michigan Health System, Ann Arbor, MI. · 3 Michigan Radiology Quality Collaborative, University of Michigan Health System, Ann Arbor, MI. · 4 Division of Pediatric Gastroenterology, Department of Pediatrics and Communicable Diseases, C. S. Mott Children's Hospital, University of Michigan Health System, Ann Arbor, MI. · 5 Division of Biostatistics and Epidemiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH. · 6 Division of Abdominal Imaging, Department of Radiology, University of Michigan Health System, Ann Arbor, MI. ·AJR Am J Roentgenol · Pubmed #27505635.

ABSTRACT: OBJECTIVE: The purpose of this study was to determine prospectively whether bowel wall apparent diffusion coefficient (ADC) measurements can be used to monitor treatment response to infliximab therapy in the setting of pediatric small-bowel Crohn disease. SUBJECTS AND METHODS: Twenty-eight pediatric subjects with newly diagnosed biopsy-proven Crohn disease of the distal or terminal ileum treated with infliximab were enrolled. Subjects underwent MR enterography at baseline, 1 month after therapy, and 6 months after therapy. Imaging features were documented, including bowel wall ADC and arterial or enteric phase contrast-enhanced signal intensity normalized to that of unenhanced imaging. A linear mixed model assessed the relationship between ADC and time; patient age and sex and azathioprine combination therapy were covariates. The diagnostic performance (with 95% CIs) of an increase in bowel wall ADC of 20% or more for identifying response to infliximab was calculated using a decrease in normalized contrast-enhanced bowel wall signal intensity of 20% or more as the reference standard. RESULTS: Bowel wall ADC increased over time (mean [± SD], 1180 ± 200 × 10 CONCLUSION: Bowel wall ADC increases over time in pediatric subjects receiving infliximab, but the diagnostic performance of ADC is likely insufficient for reliable treatment monitoring.

4 Article Prospective cohort study of ultrasound-ultrasound and ultrasound-MR enterography agreement in the evaluation of pediatric small bowel Crohn disease. 2016

Dillman, Jonathan R / Smith, Ethan A / Sanchez, Ramon / DiPietro, Michael A / Dehkordy, Soudabeh Fazeli / Adler, Jeremy / DeMatos-Maillard, Vera / Khalatbari, Shokoufeh / Davenport, Matthew S. ·Department of Radiology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave., Cincinnati, OH, 45229-3039, USA. jonathan.dillman@cchmc.org. · Department of Radiology, Section of Pediatric Radiology, University of Michigan Health System, C.S. Mott Children's Hospital, Ann Arbor, MI, USA. · Department of Pediatrics, Division of Pediatric Gastroenterology, University of Michigan Health System, C.S. Mott Children's Hospital, Ann Arbor, MI, USA. · Michigan Institute for Clinical and Health Research, University of Michigan, Ann Arbor, MI, USA. · Department of Radiology, Division of Abdominal Imaging, University of Michigan Health System, University of Michigan Hospital, Ann Arbor, MI, USA. ·Pediatr Radiol · Pubmed #26718197.

ABSTRACT: BACKGROUND: There is a paucity of published literature describing ultrasound (US)-US and US-MR enterography (MRE) inter-radiologist agreement in pediatric small bowel Crohn disease. OBJECTIVE: To prospectively assess US-US and US-MRE inter-radiologist agreement in pediatric small bowel Crohn disease. MATERIALS AND METHODS: Institutional Review Board approval and informed consent/assent were obtained for this HIPAA-compliant prospective cohort study of children with newly diagnosed distal small bowel Crohn disease (July 2012 to December 2014). Enrolled subjects (n = 29) underwent two small bowel US examinations performed by blinded independent radiologists both before and at multiple time points after initiation of medical therapy (231 unique US examinations, in total); 134 US examinations were associated with concurrent MRE. The MRE examination was interpreted by a third blinded radiologist. The following was documented on each examination: involved length of ileum (cm); maximum bowel wall thickness (mm); amount of bowel wall and mesenteric Doppler signal, and presence of stricture, penetrating disease and/or abscess. Inter-radiologist agreement was assessed with single-measure, three-way, mixed-model intra-class correlation coefficients (ICC) and prevalence-adjusted, bias-adjusted kappa statistics (κ). Numbers in brackets are 95% confidence intervals. RESULTS: Ultrasound-US agreement was moderate for involved length (ICC: 0.41 [0.35-0.49]); substantial for maximum bowel wall thickness (ICC: 0.67 [0.64-0.70]); moderate for bowel wall Doppler signal (ICC: 0.53 [0.48-0.59]); slight for mesenteric Doppler signal (ICC: 0.25 [0.18-0.42]), and moderate to almost perfect for stricture (κ: 0.54), penetrating disease (κ: 0.80), and abscess (κ: 0.96). US-MRE agreement was moderate for involved length (ICC: 0.42 [0.37-0.49]); substantial for maximum bowel wall thickness (ICC: 0.66 [0.65-0.69]), and substantial to almost perfect for stricture (κ: 0.61), penetrating disease (κ: 0.72) and abscess (κ: 0.88). CONCLUSION: Ultrasound-US agreement was similar to US-MRE agreement for assessing pediatric small bowel Crohn disease. Discrepancies in US-US and US-MRE reporting question the utility of US as an accurate, reproducible radiologic biomarker for assessing response to medical therapy and disease-related complications.

5 Article Association between genetic variants in the HNF4A gene and childhood-onset Crohn's disease. 2012

Marcil, V / Sinnett, D / Seidman, E / Boudreau, F / Gendron, F-P / Beaulieu, J-F / Menard, D / Lambert, M / Bitton, A / Sanchez, R / Amre, D / Levy, E. ·Departments of Medicine and Pediatrics, Research Institute, McGill University, Montreal, Quebec, Canada. ·Genes Immun · Pubmed #22914433.

ABSTRACT: Hepatocyte nuclear 4 alpha (HNF4α), involved in glucose and lipid metabolism, has been linked to intestinal inflammation and abnormal mucosal permeability. Moreover, in a genome-wide association study, the HNF4A locus has been associated with ulcerative colitis. The objective of our study was to evaluate the association between HNF4α genetic variants and Crohn's disease (CD) in two distinct Canadian pediatric cohorts. The sequencing of the HNF4A gene in 40 French Canadian patients led to the identification of 27 single nucleotide polymorphism (SNP)s with a minor allele frequency >5%. To assess the impact of these SNPs on disease susceptibility, we first conducted a case-control discovery study on 358 subjects with CD and 542 controls. We then carried out a replication study in a separate cohort of 416 cases and 1208 controls. In the discovery cohort, the genotyping of the identified SNPs revealed that six were significantly associated with CD. Among them, rs1884613 was replicated in the second CD cohort (odds ratio (OR): 1.33; P<0.012) and this association remained significant when both cohorts were combined and after correction for multiple testing (OR: 1.39; P<0.004). An 8-marker P2 promoter haplotype containing rs1884613 was also found associated with CD (P<2.09 × 10(-4) for combined cohorts). This is the first report showing that the HNF4A locus may be a common genetic determinant of childhood-onset CD. These findings highlight the importance of the intestinal epithelium and oxidative protection in the pathogenesis of CD.