Marian D Pfefferkorn

SickKids, Toronto, Ontario, Canada

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Publications (93)548.43 Total impact

  • Journal of Crohn s and Colitis 09/2014; 8:S400. · 3.56 Impact Factor
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    ABSTRACT: Methotrexate (MTX) use as an alternative to thiopurines in the treatment of Crohn's disease (CD) in children is increasing. This study was undertaken to assess safety and efficacy of MTX in children with CD.
    Inflammatory Bowel Diseases 06/2014; · 5.12 Impact Factor
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    ABSTRACT: Inflammatory bowel disease associated liver diseases (IBD-LDs) include autoimmune hepatitis (AIH), primary sclerosing cholangitis (PSC) and an overlap syndrome. Prospective unbiased multi-center data regarding the frequency of IBD-LD in pediatric IBD patients is lacking. We examined early alanine amino transferase (ALT) and gamma glutamyl transpeptidase (GGT) elevations in children diagnosed with IBD and assessed the likelihood of IBD-lD. Data came from the prospective observational Pediatric IBD Collaborative Research Group Registry (PIBDCR) enrolling children <16 years within 30 days of diagnosis. AIH, PSC and overlap syndrome were diagnosed by local institutional criteria. 1569 subjects had liver enzymes available. 757 had both ALT and GGT, 800 had ALT only (no GGT) and 12 had GGT only (no ALT). Overall, 29/1569 patients (1.8%) had IBD-LD. IBD-LD was diagnosed in 1/661 (0.15%) of patients with both ALT and GGT≤50 IU/L compared to 21/42 (50%) of patients with both ALT and GGT>50 (odds ratio 660, P < 0.0001) Of the 29 patients with IBD-LD, 21 had PSC, 2 AIH and 6 overlap syndrome. IBD-LD was more common in patients with ulcerative colitis (UC) and IBD-unclassified (IBD-U) than in those with Crohn's Disease (CD) (4% vs. 0.8% respectively. P < 0.001). Elevation of both ALT and GGT within 90 days after diagnosis of IBD is associated with a markedly increased likelihood of IBD-LD. Both ALT and GGT levels should be measured in all pediatric patients newly diagnosed with IBD.
    Journal of pediatric gastroenterology and nutrition 05/2014; · 2.18 Impact Factor
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    ABSTRACT: & Aims: Standard therapy for children newly diagnosed with Crohn's disease CD includes early administration of immunomodulators after initial treatment with corticosteroids. We compared the effectiveness of early ≤3 months after diagnosis treatment with an anti-tumor necrosis factor TNFα with that of an immunomodulator in attaining clinical remission and facilitating growth of pediatric patients. We analyzed data from the RISK Study, an observational research program that enrolled patients <17 y old diagnosed with inflammatory non-penetrating, non-stricturing CD from 2008 through 2012 at 28 pediatric gastroenterology centers in North America. Patients were managed by physician dictate. From 552 children median age 11.8 y, 61% male, 63% with pediatric CD activity index scores>30, and median level of C-reactive protein 5.6-fold the upper limit of normal, we used propensity score methodology to identify 68 triads of patients matched for baseline characteristics who were treated with early anti-TNFα therapy, early IM, or no early immunotherapy. We evaluated relationships among therapies, corticosteroid and surgery-free remission pediatric CD activity index scores ≤10, and growth at 1 y for 204 children. Treatment following 3 months was a covariate. Early treatment with anti-TNFα was superior to early treatment with an immunomodulator 85.3% vs 60.3% in remission; relative risk [RR]=1.41; 95% confidence interval [CI], 1.14-1.75; P=.0017, whereas early immunomodulator therapy was no different than no early immunotherapy 60.3% vs 54.4% in remission; RR=1.11; 95% CI, 0.83-1.48; P=.49 in achieving remission at 1 y. Accounting for therapy >3 months, early treatment with anti-TNFα remained superior to early treatment with an immunomodulator RR=1.51; 95% CI, 1.20-1.89; P=.0004, whereas early immunomodulator therapy was no different than no early immunotherapy RR=1.00; 95% CI, 0.75-1.34; P=.99. The mean height z-score increased compared to baseline only the early anti-TNFα group. In children newly diagnosed with comparably severe CD, early monotherapy with anti-TNFαproduced better overall clinical and growth outcomes at 1 y than early monotherapy with an immunomodulator. Further data will be required to best identify children most likely to benefit from early treatment with anti-TNFα therapy.
    Gastroenterology 10/2013; · 12.82 Impact Factor
  • Journal of pediatric gastroenterology and nutrition 06/2013; · 2.18 Impact Factor
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    ABSTRACT: OBJECTIVES:: Despite a paucity of published supporting data, 5-aminosalicylate (5-ASA) use in pediatric ulcerative colitis (UC) is common. This study describes the use and outcome of a large multicenter inception cohort of children with UC treated with 5-ASA. METHODS:: Data were obtained from the Pediatric Inflammatory Bowel Disease Collaborative Research Group Registry, a prospective North American observational study of newly diagnosed children with IBD≤16 years of age. Patient data are recorded at diagnosis, 30 days, and then quarterly. Patients are managed by physician dictate not protocol. Disease activity is classified by physician global assessment (PGA). The primary outcome examined was corticosteroid (CS)-free, inactive UC at 1 year following initiation of 5-ASA within 30 days of diagnosis (with or without concomitant CS use) without the need for rescue therapy (immunomodulators, biologics or colectomy). RESULTS:: Study subjects included 213 patients newly diagnosed with UC who received oral 5-ASA compounds (115 of whom also received CS) during the first 30 days after diagnosis, and no other oral therapies for the treatment of UC. Of these 213 patients, 86 (40%) were CS-free and PGA inactive at 1 year without rescue. Outcome was not associated with disease severity at diagnosis, demographic or laboratory factors examined, or initial dose of 5-ASA used. CONCLUSION:: 40% of children started on 5-ASA as primary maintenance therapy at diagnosis are in corticosteroid free remission after 1 year of treatment. Further pediatric studies will be needed to address whether increased adherence and/or higher dosing schedules will improve outcomes.
    Journal of pediatric gastroenterology and nutrition 07/2012; · 2.18 Impact Factor
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    ABSTRACT: Budesonide (BUD) is being used in pediatric Crohn disease (CD) because it is believed to have the potential to reduce corticosteroid-related toxicity; however, few data are available describing its use. The aim of the present study was to describe BUD use in an inception cohort of pediatric patients with CD. Data were derived from the prospective Pediatric IBD Collaborative Research Group Registry established in 2002 in North America. Use of BUD in children with CD was examined. BUD was used in 119 of 932 (13%) of children with newly diagnosed CD, with 56 of 119 (47%) starting BUD ≤ 30 days of diagnosis (26/56 with ileum and/or ascending colon [IAC] disease). BUD was used as monotherapy (9%), in combination with 5-aminosalicylates (77%), or in combination with immunomodulators (43%). Forty-three percent (24/56) went on to receive conventional corticosteroid at some point following their first BUD course. For the 63 of 119 (53%) who started BUD beyond the diagnosis period, 51 of 63 (81%) also received prednisone, with BUD used as a means of weaning from prednisone in 17 of 63 (27%). Patients with IAC disease who received BUD ≤ 30 days of diagnosis were just as likely to have received conventional corticosteroids by 1 year as were those who did not receive BUD ≤ 30 days of diagnosis. Two-thirds (77/119) of patients received BUD for ≤ 6 months. BUD is being used among pediatric patients newly diagnosed as having CD, although the majority does not have disease limited to the IAC. BUD monotherapy was rare, and further data are required to better define the role of BUD in the treatment of pediatric CD.
    Journal of pediatric gastroenterology and nutrition 01/2012; 55(2):200-4. · 2.18 Impact Factor
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    ABSTRACT: Eosinophilic esophagitis (EE) continues to present clinical challenges, including a need for noninvasive tools to manage the disease. To identify a marker able to assess disease status in lieu of repeated endoscopies, we examined 3 noninvasive biomarkers, serum interleukin (IL)-5, serum eosinophil-derived neurotoxin (EDN), and stool EDN, and examined possible correlations of these with disease phenotype and activity (symptoms and histology) in a longitudinal study of children with EE. Children with EE were studied for up to 24 weeks (12 weeks on 1 of 2 corticosteroid therapies and 12 weeks off therapy). Twenty children with normal esophagogastroduodenoscopies with biopsies were enrolled as controls. Serum IL-5, serum EDN, and stool EDN were measured at weeks 0, 4, 12, 18, and 24 in children with EE, and at baseline alone for controls. Primary and secondary statistical analyses (excluding and including outlier values of the biomarkers, respectively) were performed. Sixty subjects with EE (46 [75%] boys, mean age 7.5 ± 4.4 years) and 20 normal controls (10 [50%] boys, mean age 6.7 ± 4.1 years) were included. Significant changes in serum EDN (significant decrease from baseline to week 4, and then rebound from week 4 to week 12) occurred. Serum EDN levels were stable after week 12. Serum IL-5 and stool EDN levels in subjects with EE were not statistically different from those of the control subjects when each time point for the cases was compared with the controls' 1-time measurement. Serum EDN levels were significantly higher in subjects with EE than in controls, and the results suggest a possible role, after additional future studies, for serum EDN in establishing EE diagnosis, assessing response to therapy, and/or monitoring for relapse or quiescence.
    Journal of pediatric gastroenterology and nutrition 06/2011; 53(6):651-8. · 2.18 Impact Factor
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    ABSTRACT: The aim of the present study was to report the global experience with placement, complication rate, and recording of esophageal pH using the BRAVO capsule at our institution. We recorded the rate of any technical problems and complications during placement in all of the patients (ages 4-22 years) who received this device during a 2-year period. All of the patients undergoing esophagogastroduodenoscopy with the placement of BRAVO pH capsule were included in this analysis. We also examined the pH data recorded on days 1 and 2 for significant day-to-day variability during 2 days of pH monitoring. Two hundred eighty-nine BRAVO pH probes were placed from January 1, 2006 to December 31, 2008. At least 1 day of data was obtained in 278 patients (96.2%). Two days of data were obtained in 274 patients (94.8%). Of all of the reported complications, 1% occurred before deployment of the capsule, 4% occurred during deployment of the capsule, and 9% occurred after successful deployment of the capsule. One patient experienced a superficial esophageal tear that was associated with failure of the capsule to release from the delivery system. No patient requested removal of the capsule and all of the capsules detached within 14 days. In 9.12% of our patients, reflux index was normal on day 1 and abnormal on day 2. There was no statistically significant difference between reflux index recorded on day 1 versus day 2 (P = 0.686). The BRAVO pH capsule is easy to place, safe, and well tolerated by children. Performing a 48-hour study detected abnormal reflux in an additional 9% of our patients.
    Journal of pediatric gastroenterology and nutrition 04/2011; 53(4):404-8. · 2.18 Impact Factor
  • Rana F Ammoury, Marian D Pfefferkorn
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    ABSTRACT: Esophageal Crohn disease (ECD) is more common than it was originally thought to be. Only limited information, however, is available regarding its significance and effect on clinical course in the pediatric population. The aim of the study was to determine the prevalence of ECD in our patient population and compare clinical features and severity of disease among patients with ECD and nonesophageal Crohn disease (NECD). Medical records of all patients with ECD diagnosed during a 12-year period based on specific endoscopic and histological criteria were reviewed and compared with a random group of patients with NECD. During the study period, 81 (20%) patients with ECD were identified. Mean age at diagnosis was 12 (range 4-19 years) with a male predominance of 63%. Only 29 (36%) patients had symptoms suggestive of upper gastrointestinal involvement. Endoscopic ulcers were present in 45 (56%) of patients with ECD, whereas noncaseating granulomas were found in 10 (12%) of those patients. The majority (89%) of these patients had concomitant gastric and/or duodenal involvement. When compared with 160 random patients with NECD, patients with ECD had higher mean Pediatric Crohn Disease Activity Index scores (40.2 vs 23.9; P < 0.001), more penetrating-type disease (12% vs 2%; P = 0.001), and a greater frequency of perianal involvement (51% vs 33%; P = 0.005) at diagnosis. No differences, however, were noted between the 2 groups in terms of need for surgical resection throughout duration of follow-up. Patients with ECD may represent a phenotype of Crohn disease with a more severe presentation. Patients with perianal disease at the time of initial physical examination should be considered for an upper endoscopy in addition to the colonoscopy to exclude esophageal involvement despite the absence of specific upper gastrointestinal symptoms. These observations should foster additional investigation into ECD phenotype to determine appropriate treatment and prognosis.
    Journal of pediatric gastroenterology and nutrition 03/2011; 52(3):291-4. · 2.18 Impact Factor
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    ABSTRACT: The Pediatric Crohn's Disease Activity Index (PCDAI) has become the standard outcome measure in pediatric Crohn's disease (CD) clinical research. Other versions have been proposed but without systematic evaluation. The aim was to assess validity and responsiveness of the abbreviated PCDAI (abbrPCDAI), short PCDAI (shPCDAI), and modified PCDAI (modPCDAI) as measures of disease activity and to compare these with a mathematically weighted version developed here (wPCDAI). The raw data from four prospectively collected datasets were used, totaling 437 children with CD (including two clinical trials). Discriminant validity utilized physician global assessment of disease activity (PGA), and construct validity the correlation with PGA and laboratory results. Feasibility and face validity were ascertained by a survey of 33 experts in pediatric CD. The wPCDAI had better performance than the PCDAI in construct validity and responsiveness and it discriminated better between the disease activity categories (area under the receiver operator characteristic [ROC] 0.97; 95% confidence interval [CI]: 0.95-0.99). In comparison to the original PCDAI, the noninvasive versions (abbrPCDAI and shPCDAI) had lower face, construct, and discriminant validity but were judged to be significantly more feasible. The modPCDAI performed well in the construct validation but was consistently inferior in all other parameters. Cutoffs that correspond to remission, response, and gradations of disease activity were determined for each index. The newly weighted wPCDAI performed better than the original PCDAI and is more feasible. The noninvasive versions (shPCDAI and abbrPCDAI) are inferior to the full PCDAI, but when needed in retrospective studies either may be equally used.
    Inflammatory Bowel Diseases 02/2011; 18(1):55-62. · 5.12 Impact Factor
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    ABSTRACT: Despite little supporting data, thiopurine use is common in pediatric ulcerative colitis (UC). Our aim was to determine outcome following thiopurine use in a multicenter inception cohort of children diagnosed with UC. Data were obtained from a prospective observational study of newly diagnosed children <16 years of age. Data are recorded at diagnosis, 30 days, and quarterly. Patients are managed by physician dictates not protocol. Disease activity is classified by physician global assessment. The primary outcome was corticosteroid (CS)-free inactive UC at 1 year following thiopurine initiation without the need for rescue therapy (infliximab, calcineurin inhibitors, or colectomy). Of 1,490 patients in our registry, 394 have UC (mean age at diagnosis 11.3±3.7 years); 197 (50%) received thiopurine (49% ≤3 months from diagnosis). Also, 84% were receiving CSs and 60% 5-aminosalicylates at thiopurine start. Of the 197 patients, there was insufficient follow-up (41), previous or concomitant use of infliximab (16), or calcineurin inhibitor (7), leaving 133 patients evaluable at 1 year. Of these, 65 (49%) had CS-free inactive UC without rescue therapy. CS-free inactive disease at 1 year after initiating thiopurine was not affected by starting thiopurine ≤3 months vs. >3 months from diagnosis, gender, age, or concomitant treatment with 5-aminosalicylates. Kaplan-Meier analysis showed that the likelihood of remaining free of rescue therapy in the thiopurine-treated patients was 73% at 1 year. Approximately 50% of children with UC starting thiopurine without previous or concomitant biologic or calcineurin inhibitor therapy have CS-free inactive disease 1 year later without the need for rescue therapy.
    The American Journal of Gastroenterology 01/2011; 106(5):981-7. · 9.21 Impact Factor
  • Gastroenterology 01/2011; 140(5). · 12.82 Impact Factor
  • Gastroenterology 01/2011; 140(5). · 12.82 Impact Factor
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    ABSTRACT: The primary purpose of this study was to test whether recombinant human growth hormone (rhGH) supplementation would enhance protein synthesis and accretion of lean body mass. Eight adolescents (six males and two females; 17.2 +/- 2.6 years; age range, 13.7-21.2 years) participated in a randomized double-blind placebo-controlled cross-over trial of rhGH. We employed stable isotopes to measure proteolysis and protein synthesis during fasting and fed conditions during two 6-month treatment conditions. We also measured bone mineral density (BMD), markers of bone turnover, and body composition. Whole-body proteolysis, phenylalanine catabolism, and protein synthesis did not differ during treatment with rhGH vs. placebo. Enteral nutrition suppressed proteolysis and increased protein synthesis similarly during placebo and rhGH treatments. We conclude that rhGH is unlikely to provide sufficient metabolic benefit to warrant its use as an adjunct treatment in clinically stable adolescents with Crohn disease. A high prevalence of vitamin D deficiency and suboptimal BMD existed, which deserves further investigation and clinical attention.
    Journal of pediatric endocrinology & metabolism: JPEM 01/2011; 24(9-10):633-40. · 0.71 Impact Factor
  • Gastroenterology 01/2011; 140(5). · 12.82 Impact Factor
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    ABSTRACT: Fecal lactoferrin (FL) is a noninvasive biomarker that is elevated in Crohn disease (CD) compared to irritable bowel syndrome. The purpose of this study was to evaluate FL in identifying children with active versus inactive CD. Fresh stool samples were collected from children with CD scheduled for endoscopy or a clinic visit, and from new outpatients who were scheduled for colonoscopy. FL was determined using a polyclonal antibody-based enzyme-linked immunosorbent assay. Physical global assessment, endoscopic findings, erythrocyte sedimentation rate (ESR), and the Pediatric CD Activity Index (PCDAI) were recorded for patients with CD. The PCDAI scores symptoms, laboratory parameters, physical examination, and extraintestinal manifestations. A score of ≤10 is inactive disease, 11 to 30 is mild active, and ≤31 is moderate to severe active. Of 101 study patients (4- to 20-year-old, 66 boys), 31 had active CD, 23 had inactive CD, and 37 had noninflammatory bowel disease (non-IBD) conditions. Four patients with ulcerative colitis and 6 patients with polyposis were excluded from analysis. FL was significantly elevated in CD versus non-IBD (P < 0.001) and in active versus inactive CD (P < 0.001). The PCDAI and ESR were higher in active CD than in inactive CD (both P < 0.001). Using an FL cutoff of 7.25 μg/g, FL has 100% sensitivity and 100% negative predictive value in detecting active CD. Using an FL cutoff level of 60 μg/g, FL had 84% sensitivity, 74% specificity, 81% positive predictive value, and 77% negative predictive value for detecting active CD. FL is a promising biomarker of active CD and may be more practical to use when it is not feasible to obtain all of the necessary clinical information for the PCDAI.
    Journal of pediatric gastroenterology and nutrition 10/2010; 51(4):425-8. · 2.18 Impact Factor
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    ABSTRACT: We examined the incidence of Crohn's disease (CD)-related surgery in a multi-center, inception cohort of pediatric patients with CD. We also examined the effect of starting immunomodulator therapy within 30 days of diagnosis. Data from 854 children with CD from the Pediatric Inflammatory Bowel Disease Collaborative Research Group who were diagnosed with CD between 2002 and 2008 were analyzed. Overall, 76 (9%) underwent a first CD-related surgery, 57 (7%) underwent a first bowel surgery (bowel resection, ostomy, strictureplasty, or appendectomy), and 19 (2%) underwent a first non-bowel surgery (abscess drainage or fistulotomy). The cumulative risks for bowel surgery, non-bowel surgery, and all CD-related surgeries were 3.4%, 1.4%, and 4.8%, respectively, at 1 year after diagnosis and 13.8%, 4.5%, and 17.7%, respectively, at 5 years after diagnosis. Older age at diagnosis, greater disease severity, and stricturing or penetrating disease increased the risk of bowel surgery. Disease between the transverse colon and rectum decreased the risk. Initiation of immunomodulator therapy within 30 days of diagnosis, sex, race, and family history of inflammatory bowel disease did not influence the risk of bowel surgery. In an analysis of pediatric patients with CD, the 5-year cumulative risk of bowel surgery was lower than that reported in recent studies of adult and pediatric patients but similar to that of a recent retrospective pediatric study. Initiation of immunomodulator therapy at diagnosis did not alter the risk of surgery within 5 years of diagnosis.
    Clinical gastroenterology and hepatology: the official clinical practice journal of the American Gastroenterological Association 09/2010; 8(9):789-94. · 5.64 Impact Factor
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    ABSTRACT: Infliximab is effective in treating moderate/severe ulcerative colitis (UC) in adults. The aim of this study was to determine the outcome after treatment with infliximab in pediatric UC. We performed a multicenter cohort study of 332 pediatric patients with UC enrolled in the Pediatric Inflammatory Bowel Disease Collaborative Research Group Registry. Children<or=16 years of age and newly diagnosed with UC are enrolled in the registry. Disease and medication information are collected prospectively from the treating physician at diagnosis, 30 days, and quarterly thereafter. No interventions were specified, per protocol. Of 332 patients, 52 (16%) received infliximab (23%<3 months from diagnosis, 38% 3-12 months, 38% >12 months). Mean age at infliximab initiation was 13.3+/-2.6 (range 6-17) years; 87% of patients had pancolitis. Median follow-up was 30 months. Continuous maintenance (CM) therapy was given in 65%, episodic in 21%, episodic converted to CM in 6%, and insufficient data in 8% of patients. Sixty-three percent of patients were corticosteroid refractory, and 35% were corticosteroid dependent. Concomitant medications at first infliximab infusion included corticosteroids (87%), thiopurines (63%), and 5-aminosalicylates (51%). Corticosteroid-free inactive disease by physician global assessment was noted in 12/44 (27%), 15/39 (38%), and 6/28 (21%) patients at 6, 12, and 24 months, respectively. Kaplan-Meier analysis showed that the likelihood of remaining colectomy free after treatment with infliximab was 75% at 6 months, 72% at 12 months, and 61% at 2 years. In this cohort of children with UC receiving infliximab, corticosteroid-free inactive disease was observed in 38 and 21% of patients at 12 and 24 months, respectively. By 24 months, 61% of patients had avoided colectomy.
    The American Journal of Gastroenterology 06/2010; 105(6):1430-6. · 9.21 Impact Factor
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    ABSTRACT: Although it is known that extraintestinal manifestations (EIMs) commonly occur in pediatric inflammatory bowel disease (IBD), little research has examined rates of EIMs and their relation to other disease-related factors in this population. The purpose of this study was to determine the rates of EIMs in pediatric IBD and examine correlations with age, sex, diagnosis, disease severity, and distribution. Data were prospectively collected as part of the Pediatric IBD Collaborative Research Group Registry, an observational database enrolling newly diagnosed IBD patients <16 years old since 2002. Rates of EIM (occurring anytime during the period of enrollment) and the aforementioned variables (at baseline) were examined. Patients with indeterminate colitis were excluded from the analysis given the relatively small number of patients. One thousand nine patients were enrolled (mean age 11.6 +/- 3.1 years, 57.5% boys, mean follow-up 26.2 +/- 18.2 months). Two hundred eighty-five (28.2%) patients experienced 1 or more EIMs. Eighty-seven percent of EIM occurred within the first year. Increased disease severity at baseline (mild vs moderate/severe) was associated with the occurrence of any EIM (P < 0.001), arthralgia (P = 0.024), aphthous stomatitis (P = 0.001), and erythema nodosum (P = 0.009) for both Crohn disease (CD) and ulcerative colitis (UC) during the period of follow-up. Statistically significant differences in the rates of EIMs between CD and UC were seen for aphthous stomatitis, erythema nodosum, and sclerosing cholangitis. EIMs as defined in this study occur in approximately one quarter of pediatric patients with IBD. Disease type and disease severity were commonly associated with the occurrence of EIMs.
    Journal of pediatric gastroenterology and nutrition 05/2010; 51(2):140-5. · 2.18 Impact Factor

Publication Stats

1k Citations
548.43 Total Impact Points


  • 2013
    • SickKids
      Toronto, Ontario, Canada
    • Boston Children's Hospital
      Boston, Massachusetts, United States
  • 2002–2013
    • Riley Hospital for Children
      Indianapolis, Indiana, United States
  • 2006–2012
    • IWK Health Centre
      Halifax, Nova Scotia, Canada
  • 2008–2011
    • Connecticut Children's Medical Center
      Hartford, Connecticut, United States
    • Childrens Hospital of Pittsburgh
      • Division of Pediatric Gastroenterology, Hepatology and Nutrition
      Pittsburgh, PA, United States
    • North Shore-LIJ Health System
      Manhasset, New York, United States
    • The Ohio State University
      Columbus, Ohio, United States
  • 2002–2011
    • Indiana University-Purdue University Indianapolis
      Indianapolis, Indiana, United States
  • 2010
    • Nationwide Children's Hospital
      Columbus, Ohio, United States
  • 2009
    • Atlantic Health System
      Morristown, New Jersey, United States
  • 2007
    • University of Pittsburgh
      • Department of Pediatrics
      Pittsburgh, PA, United States