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Lightner, Amy L.

https://orcid.org/0000-0002-0459-0699

Mayo Clinic

Scripps Health

Citations 64

Colorectal cAncer and CrohN's DIsease study (CANDID): An international multicentre retrospective audit
Garoufalia, Zoe , Dourado, Justin , Boutros, Marylise , Celentano, Valerio , Davies, Justin , Fleshner, Phillip , Gefen, Rachel , Holubar, Stefan D. , El‐Hussuna, Alaa , Keller, Deborah S. , Pellino, Gianluca , Shawki, Sherief , Siakavellas, Spyros I. , Spinelli, Antonino , Warusavitarne, Janindra, Wexner, Steven D. , Spinelli, Antonino , Holubar, Stefan D , Wexner, Steven D , Emile, Sameh Hany , Brady, R , Horesh, Nir , Lightner, Amy L.

Colorectal Disease | January 27, 2025 | Volume: 27 | Issue: 2 | Pages: No page available

10.1111/codi.70005 Get It

AbstractBackgroundInflammatory bowel disease (IBD) affects more than 10 million people worldwide. Men and women are equally affected by Crohn's disease (CD). It has been shown that patients with CD are at an increased risk of a colorectal cancer (CRC) diagnosis and CRC‐related mortality. During the last two decades, biological therapies have revolutionized the treatment of CD. There are no current studies investigating the prevalence of CRC in patients with CD in the era of biological therapy and the possible features of patients with CD who are at high risk of developing CRC.AimWe aim to assess the prevalence of CRC, risk factors and profile of CRC in patients with CD receiving biological treatment compared with those who are not under biological therapy and the impact of CD‐associated colorectal strictures on CRC development. The study hypothesis is that the use of biological therapy in the control of CD activity may decrease the risk of developing CRC.Study design and settingAn international, retrospective, snapshot of the prevalence of CRC in patients with CD, reported according to the SPIRIT guidelines. The study will involve centres that hold regular IBD multidisciplinary team meetings and have both IBD colorectal surgeons and gastroenterologists. Each participating centre will provide a local consultant lead and a local trainee lead. Data will be collected within a 2‐year recruitment period (January 2017–January 2019).Study populationAdult patients who presented with CD during the study period. Patients with an incidental diagnosis of CD during evaluation for CRC will be excluded.Statistical planBaseline patient characteristics will be summarized using the appropriate descriptive statistics. Univariable, multivariable and Cox regression models will be used to identify factors significantly associated with CRC. For noncontinuous variables a comparison between the subgroups will be carried out using the chi‐square test corrected by Fisher's exact test if appropriate. A p‐value of <0.05 will be considered statistically significant.Data storageData will be stored on a secured server, pin‐code protected according to the local data management agreement.
Durable Response in Patients With Refractory Fistulizing Perianal Crohn’s Disease Using Autologous Mesenchymal Stem Cells on a Dissolvable Matrix: Results from the Phase I Stem Cell on Matrix Plug Trial
Dozois, Eric J. , Dietz, Allan B. , Lee, Yong S. , Friton, Jessica, Faubion, William A. , Friton, Jessica J, Dietz, Allan B , Lightner, Amy L. , Fletcher, Joel G.

Diseases of the Colon & Rectum | December 20, 2022 | Volume: 66 | Issue: 2 | Pages: 243-252

10.1097/dcr.0000000000002579 Get It

BACKGROUND: Refractory perianal Crohn’s disease remains notoriously difficult to treat. We developed a novel technology using a commercially available bioabsorbable fistula plug to deliver autologous adipose-derived mesenchymal stem cells. OBJECTIVE: This study aimed to assess therapeutic safety and feasibility in the completed STOMP (stem cells on matrix plugs) phase 1 clinical trial. DESIGN: Prospective single-arm phase I clinical trial. SETTING: Tertiary academic medical center. PATIENTS: Adults (aged 18–65 y) with complex single-tract Crohn’s disease perianal fistula who have failed conventional therapy were included in this study. INTERVENTION: Autologous adipose-derived mesenchymal stem cells were isolated, ex vivo culture expanded, and seeded onto a commercially available bioabsorbable fistula plug. Six weeks later, patients returned to the operating room for removal of the seton and placement of the stem cell-loaded plug. MAIN OUTCOME MEASURES: Patients were followed up for a total of 8 visits through 12 months. Safety was the primary end point; clinical healing and MRI response were secondary end points. RESULTS: Twenty patients (12 females; mean age 36 y) were treated with the stem cell–loaded plug. Of the 20 patients enrolled, 3 were not included in the 12-month analysis because of study withdrawal. Through 12 months, no patient experienced a serious adverse event related to the stem cell–loaded plug. Four patients experienced 7 serious adverse events and 12 patients experienced 22 adverse events. Complete clinical healing occurred in 14 of 18 patients at 6 months and 13 of 17 patients at 12 months. MRI response was observed in 12 of 18 patients at 6 months. LIMITATIONS: The main limitations were the small sample size and restrictive inclusion criteria. CONCLUSIONS: A stem cell–loaded plug can safely and effectively deliver cell-based therapy for patients with single-tract fistulizing perianal Crohn’s disease. See Video Abstract at http://links.lww.com/DCR/C70. RESPUESTA DURADERA OBSERVADA EN PACIENTES CON ENFERMEDAD DE CROHN PERIANAL FISTULIZANTE REFRACTARIA MEDIANTE EL USO DE CÉLULAS MADRE MESENQUIMALES AUTÓLOGAS EN UNA MATRIZ DISOLUBLE: RESULTADOS DEL ENSAYO DE FASE I STEM CELL ON MATRIX PLUG ANTECEDENTES: La enfermedad de Crohn perianal refractaria sigue siendo notoriamente difícil de tratar. Desarrollamos una tecnología novedosa utilizando un tapón de fístula bioabsorbible disponible comercialmente para administrar células madre mesenquimales derivadas de tejido adiposo autólogo. OBJETIVO: Evaluar la seguridad y viabilidad terapéutica en el ensayo finalizado STOMP. DISEÑO: Ensayo clínico prospectivo de fase I de un solo brazo. AJUSTE: Centro médico académico terciario. PACIENTES: Adultos (18-65) con fístula perianal compleja de la enfermedad de Crohn de un solo tracto que han fracasado con la terapia convencional. INTERVENCIÓN: Se aislaron células madre mesenquimales derivadas de tejido adiposo autólogo, se expandieron en cultivo ex vivo y se sembraron en un tapón de fístula bioabsorbible disponible comercialmente. Seis semanas después, los pacientes regresaron al quirófano para retirar el setón y colocar el tapón cargado de células madre. PRINCIPALES MEDIDAS DE RESULTADO: Los pacientes fueron seguidos durante un total de 8 visitas durante 12 meses. La seguridad fue el criterio principal de valoración; la curación clínica y la respuesta a la resonancia magnética fueron criterios de valoración secundarios. RESULTADOS: Veinte pacientes (12 mujeres, edad media 36 años) fueron tratados con el tapón cargado de células madre. De los 20 pacientes inscritos, tres no se incluyeron en el análisis de 12 meses porque se retiraron del estudio. A lo largo de 12 meses, ningún paciente experimentó un evento adverso grave relacionado con el tapón cargado de células madre. Cuatro pacientes experimentaron 7 eventos adversos graves y 12 pacientes experimentaron 22 eventos adversos. La curación clínica completa ocurrió en 14 de 18 pacientes a los 6 meses y en 13 de 17 pacientes a los 12 meses. La respuesta a la resonancia magnética se observó en 12 de 18 pacientes a los 6 meses. LIMITACIONES: Las principales limitaciones son el tamaño pequeño de la muestra y los criterios de inclusión restrictivos. CONCLUSIONES: Un tapón cargado de células madre se puede administrar de manera segura y efectiva, una terapia basada en células para pacientes con enfermedad de Crohn perianal fistulizante de un solo tracto. Consule Video Resumen en http://links.lww.com/DCR/C70. (Traducción— Dr. Yesenia Rojas-Khalil)
Predicting Risk of Surgery in Patients With Small Bowel Crohn’s Disease Strictures Using Computed Tomography and Magnetic Resonance Enterography
Inoue, Akitoshi , Bartlett, David J. , Shahraki, Narges, Sheedy, Shannon P. , Heiken, Jay P. , Voß, Benjamin, Fidler, Jeff L. , Tootooni, M. Samie , Sır, Mustafa Y. , Baker, Mark E. , Rieder, Florian , Deepak, Parakkal , Bruining, David H. , Voss, Benjamin A, Lightner, A L , Deepak, Parakkal , Fletcher, Joel G , Inoue, Akitoshi , Fidler, Jeff L. , Pasupathy, Kalyan S. , Lightner, Amy L. , Fletcher, Joel G.

Inflammatory Bowel Diseases | January 15, 2022 | Volume: 28 | Issue: 11 | Pages: 1677-1686

10.1093/ibd/izab332 Get It

Abstract Background We aimed to determine if patient symptoms and computed tomography enterography (CTE) and magnetic resonance enterography (MRE) imaging findings can be used to predict near-term risk of surgery in patients with small bowel Crohn’s disease (CD). Methods CD patients with small bowel strictures undergoing serial CTE or MRE were retrospectively identified. Strictures were defined by luminal narrowing, bowel wall thickening, and unequivocal proximal small bowel dilation. Harvey-Bradshaw index (HBI) was recorded. Stricture observations and measurements were performed on baseline CTE or MRE and compared to with prior and subsequent scans. Patients were divided into those who underwent surgery within 2 years and those who did not. LASSO (least absolute shrinkage and selection operator) regression models were trained and validated using 5-fold cross-validation. Results Eighty-five patients (43.7 ± 15.3 years of age at baseline scan, majority male [57.6%]) had 137 small bowel strictures. Surgery was performed in 26 patients within 2 years from baseline CTE or MRE. In univariate analysis of patients with prior exams, development of stricture on the baseline exam was associated with near-term surgery (P = .006). A mathematical model using baseline features predicting surgery within 2 years included an HBI of 5 to 7 (odds ratio [OR], 1.7 × 105; P = .057), an HBI of 8 to 16 (OR, 3.1 × 105; P = .054), anastomotic stricture (OR, 0.002; P = .091), bowel wall thickness (OR, 4.7; P = .064), penetrating behavior (OR, 3.1 × 103; P = .096), and newly developed stricture (OR: 7.2 × 107; P = .062). This model demonstrated sensitivity of 67% and specificity of 73% (area under the curve, 0.62). Conclusions CTE or MRE imaging findings in combination with HBI can potentially predict which patients will require surgery within 2 years.
The American Society of Colon and Rectal Surgeons Clinical Practice Guidelines for the Surgical Management of Ulcerative Colitis
Holubar, Stefan D. , Vogel, Jon D., Gaertner, Wolfgang B. , Davis, Bradley R. , Davis, Kurt G. , Mahadevan, Uma, Shah, Samir A. , Kane, Sunanda V. , Paquette, Ian M., Holubar, Stefan D , Lightner, Amy L. , Poylin, Vitaliy Y. , Steele, Scott R. , Feingold, Daniel L.

Diseases of the Colon & Rectum | April 17, 2021 | Volume: 64 | Issue: 7 | Pages: 783-804

10.1097/dcr.0000000000002037 Get It

The American Society of Colon and Rectal Surgeons Clinical Practice Guidelines for the Management of Clostridioides difficile Infection
Boutros, Marylise , Khanna, Sahil , Paquette, Ian M., Poylin, Vitaliy Y. , Hawkins, Alexander T. , Bhama, Anuradha R. , Lightner, Amy L. , Feingold, Daniel L.

Diseases of the Colon & Rectum | March 26, 2021 | Volume: 64 | Issue: 6 | Pages: 650-668

10.1097/dcr.0000000000002047 Get It

S0695 Appropriateness of Medical and Surgical Treatments in Patients With Chronic Inflammation of the Ileal Pouch: A RAND Panel Approach
Syal, Gaurav , Sparrow, Miles , Velayos, Fernando, Bressler, Brian , Chiefetz, Adam, Devlin, Shane , Jones, Jennifer , Raffals, Laura H., Fleshner, Phillip, Ullman, Thomas, Melmed, Gil , Melmed, Gil Y , Baidoo, Leonard , Irving, Peter Miles , Kaplan, Gilaad G. , Kozuch, Patricia L. , Gecse, Krisztina Barbara , Lightner, Amy L. , Siegel, Corey A

American Journal of Gastroenterology | October 24, 2020 | Volume: 115 | Issue: 1 | Pages: S348-S350

10.14309/01.ajg.0000704828.13102.9d Get It

Does IBD Portend Worse Outcomes in Patients with Rectal Cancer? A Case-Matched Analysis
Alsughayer, Ahmad, McKenna, Nicholas P. , Petersen, M. , Mathis, Kellie L. , Petersen, Molly, McKenna, Nicholas P , Grass, Fabian , Lightner, Amy L.

Diseases of the Colon & Rectum | August 13, 2020 | Volume: 63 | Issue: 9 | Pages: 1265-1275

10.1097/dcr.0000000000001666 Get It

BACKGROUND: Patients with IBD are at increased risk for developing colorectal cancer. However, overall survival and disease-free survival for rectal cancer alone in patients with IBD has not been reported. OBJECTIVE: This study aimed to determine overall survival and disease-free survival for patients with rectal cancer in IBD versus non-IBD cohorts. DESIGN: This is a retrospective cohort study. SETTING: This study was conducted at an IBD referral center. PATIENTS: All consecutive adult patients with IBD diagnosed with rectal cancer and at least 1 year of postsurgery follow-up were included and matched in a 1:2 fashion (age, sex, preoperative stage) with patients with rectal cancer who did not have IBD. MAIN OUTCOMES MEASURES: Five-year overall survival and disease-free survival, 30-day postoperative complication, readmission, reoperation, and mortality rates were measured. METHODS: Survival rates were calculated using Kaplan-Meier estimates. The association of risk factors and long-term outcomes was assessed using Cox proportion hazard models. RESULTS: A total of 107 study patients with IBD who had rectal cancer were matched to 215 control patients; preoperative stages were as follows: 31% with stage I, 19% with stage II, 40% with stage III, and 10% with stage IV. Differences were observed (IBD vs non-IBD) in neoadjuvant chemotherapy (33.6% vs 52.6%, p = 0.001) and preoperative radiotherapy (35.5% vs 53.5%, p = 0.003). Postoperative complication rates were similar. On surgical pathology, patients with IBD had more lymphovascular invasion (12.9% vs 5.6%, p = 0.04) and positive circumferential resection margins (5.4% vs 0.9%, p = 0.03). On multivariable analysis, the diagnosis of IBD did not significantly impact long-term mortality (HR, 0.91; 95% CI, 0.53–1.57; p = 0.73) or disease-free survival (HR, 1.36; 95% CI, 0.84–2.21; p = 0.22). LIMITATIONS: This study was limited by its retrospective design and the use of single-center data. CONCLUSIONS: Patients have rectal cancer with IBD and without IBD have similar long-term and disease-free survival, despite lower rates of neoadjuvant treatment and higher margin positivity in patients with IBD. See Video Abstract at http://links.lww.com/DCR/B271. ¿LA ENFERMEDAD INFLAMATORIA INTESTINAL ACARREA PEORES RESULTADOS EN PACIENTES CON CÁNCER RECTAL? UN ANÁLISIS DE CASOS-COINCIDENTES ANTECEDENTES: Los pacientes con enfermedad inflamatoria intestinal (EII) tienen un mayor riesgo de desarrollar cáncer colorrectal. Sin embargo, no se ha informado la supervivencia general y la supervivencia libre de enfermedad para el cáncer rectal solo en pacientes con EII. OBJETIVO: Determinar la supervivencia general y la supervivencia libre de enfermedad para pacientes con cáncer rectal en cohortes con EII versus sin EII. DISEÑO: Estudio de cohorte retrospectivo. MARCO: Centro de referencia para enfermedad inflamatoria intestinal. PACIENTES: todos los pacientes adultos con EII diagnosticados con cáncer rectal, consecutives, y al menos un año de seguimiento postoperatorio se incluyeron y se emparejaron de manera 1: 2 (edad, sexo, etapa preoperatoria) con pacientes con cáncer rectal sin EII. MEDIDAS DE RESULTADO PRINCIPALES: Se midieron la supervivencia general a cinco años y la supervivencia libre de enfermedad, complicaciones postoperatorias a los 30 días, reingreso, reoperación y tasas de mortalidad. MÉTODOS: Las tasas de supervivencia se calcularon utilizando estimaciones de Kaplan-Meier. La asociación de factores de riesgo y resultados a largo plazo se evaluó mediante modelos de riesgo de proporción de Cox. RESULTADOS: Un total de 107 pacientes con EII y cáncer rectal se compararon con 215 pacientes de control; las etapas preoperatorias fueron las siguientes: 31% de Etapa I, 19% de Etapa II, 40% de Etapa III y 10% de Etapa IV. Se observaron diferencias (EII versus no EII) en quimioterapia neoadyuvante (33.6% frente a 52.6%, p = 0.001) y radioterapia preoperatoria (35.5% frente a 53.5%, p = 0.003). Las tasas de complicaciones postoperatorias fueron similares. En la patología quirúrgica, los pacientes con EII tuvieron más invasión linfovascular (12.9% frente a 5.6%, p = 0.04) y márgenes de resección circunferencial positivos (5.4% frente a 0.9%, p = 0.03). En el análisis multivariable, el diagnóstico de EII no tuvo un impacto significativo en la mortalidad a largo plazo (HR 0.91; IC del 95%: 0.53-1.57, p = 0.73) o la supervivencia libre de enfermedad (HR 1.36; IC del 95%: 0.84-2.21, p = 0.22) LIMITACIONES: Diseño retrospectivo, centro único de datos. CONCLUSIONES: Los pacientes con EII y sin EII con cáncer rectal tienen una supervivencia similar a largo plazo y libre de enfermedad, a pesar de las tasas más bajas de tratamiento sneoadyuvante y un mayor margen positivo en pacientes con EII. Consulte Video Resumen en http://links.lww.com/DCR/B271.
The American Society of Colon and Rectal Surgeons Clinical Practice Guidelines for the Surgical Management of Crohn’s Disease
Lightner, Amy L., Vogel, Jon D., Keller, Deborah S. , Shah, Samir A. , Mahadevan, Uma, Kane, Sunanda V. , Paquette, Ian M., Lightner, Amy L. , Carmichael, Joseph C. , Steele, Scott R. , Feingold, Daniel L.

Diseases of the Colon & Rectum | July 7, 2020 | Volume: 63 | Issue: 8 | Pages: 1028-1052

10.1097/dcr.0000000000001716 Get It

The American Society of Colon and Rectal Surgeons Clinical Practice Guidelines for the Treatment of Left-Sided Colonic Diverticulitis
Hall, Jason , Lee, Sang Hong , Stocchi, Luca , Paquette, Ian M., Hardiman, Karin M. , Lightner, Amy L. , Steele, Scott R. , Feingold, Daniel L.

Diseases of the Colon & Rectum | May 8, 2020 | Volume: 63 | Issue: 6 | Pages: 728-747

10.1097/dcr.0000000000001679 Get It

Are Biologics Safe in the Immediate Postoperative Period? A Single-Center Evaluation of Consecutive Crohn’s Surgical Patients
Lightner, Amy L., Alsughayer, Ahmad M., Harmsen, William S. , Petersen, M. , Loftus, Edward V. , Petersen, Molly, Loftus, Edward V , Lightner, Amy L. , Grass, Fabian , Alsughayer, Ahmad

Diseases of the Colon & Rectum | March 9, 2020 | Volume: 63 | Issue: 7 | Pages: 934-943

10.1097/dcr.0000000000001649 Get It

BACKGROUND: There is no study to date examining the safety of initiating or restarting biologic therapy after major abdominal surgery for Crohn’s disease. OBJECTIVE: The purpose of this study was to determine differences in the rates of 90-day superficial surgical site infections, intra-abdominal sepsis, and overall postoperative infectious complications among patients who were initiated on or restarted a biologic within 90 days postoperatively compared with those who were not. DESIGN: This was a retrospective cohort study. SETTINGS: The study was conducted at an IBD referral center. PATIENTS: Adult patients with Crohn’s disease who received a biologic therapy within 90 days of a major abdominal operation between May 20, 2014, and December 31, 2018, were included. MAIN OUTCOMES MEASURES: Ninety-day superficial surgical site infection, intra-abdominal sepsis, and overall postoperative infectious complications were measured. RESULTS: A total of 680 patients with Crohn’s disease were included: 351 were initiated on biologic therapy within 90 days after surgery and 329 were not. Patients exposed to biologic therapy postoperatively were younger (p < 0.001), had a lower BMI (p = 0.0014), were less often diabetic (p = 0.0011), and were more often exposed preoperatively to biologics (p < 0.0001) and immunomodulators (p < 0.0001) but not corticosteroids (p = 0.8399). Of those exposed postoperatively, nearly all (93.7%) had been on a biologics preoperatively, and most resumed the same biologic (68.0%). The median time to starting biologic therapy postoperatively was 31 days (range, 7–89 d). Postoperative biologic exposure was not associated with an increased risk of superficial surgical site infection (HR = 1.02 (95% CI, 0.95–1.09) per week; p = 0.59), intra-abdominal sepsis (HR = 1.07 (95% CI, 0.99–1.16); p = 0.73), or overall postoperative infectious complications (HR = 1.02 (95% CI, 0.98–1.07); p = 0.338); the overall rates of each at 90 days was 13%, 8%, and 28%. LIMITATIONS: The study was limited by its retrospective design and single-center data. CONCLUSIONS: Postoperative initiation or resumption of biologic therapy did not increase 90-day rates of superficial surgical site infection, intra-abdominal sepsis, or total infectious complications after major abdominal surgery for Crohn’s disease. See Video Abstract at http://links.lww.com/DCR/B207. ¿SON SEGUROS LOS FÁRMACOS BIOLÓGICOS EN EL POSTOPERATORIO INMEDIATO? UNA EVALUACIÓN DE UN SOLO CENTRO DE PACIENTES QUIRÚRGICOS CONSECUTIVOS CON ENFERMEDAD DE CROHN ANTECEDENTES: No hay ningún estudio hasta la fecha que examine la seguridad de iniciar o reiniciar la terapia biológica después de una cirugía abdominal mayor en enfermedad de Crohn. OBJETIVO: Determinar las diferencias en las tasas a 90 días de infecciones del sitio quirúrgico superficial, sepsis intraabdominal y complicaciones infecciosas postoperatorias generales entre los pacientes en que se inició o reinició un biológico dentro de los 90 días después de la operación en comparación con aquellos que no lo recibieron. DISEÑO: Estudio de cohorte retrospectivo. ESCENARIO: Centro de referencia de enfermedad inflamatoria intestinal. PACIENTES: Pacientes adultos con enfermedad de Crohn que recibieron una terapia biológica dentro de los 90 días de una operación abdominal mayor entre el 20 de mayo de 2014 y el 31 de diciembre de 2018. PRINCIPALES MEDIDAS DE RESULTADO: Infección superficial del sitio quirúrgico, sepsis intraabdominal y complicaciones infecciosas postoperatorias generales a 90 días. RESULTADOS: Se incluyeron un total de 680 pacientes con enfermedad de Crohn: 351 se iniciaron en terapia biológica dentro de los 90 días posteriores a la cirugía y 329 no. Los pacientes expuestos a terapia biológica después de la operación eran más jóvenes (p <0.001), tenían un índice de masa corporal más bajo (p = 0.0014), eran con menos frecuencia diabéticos (p = 0.0011) y estaban expuestos con mayor frecuencia preoperatoriamente a fármacos biológicos (p <0.0001) e inmunomoduladores (p <0.0001) pero no a corticosteroides (p = 0.8399). De los expuestos postoperatoriamente, casi todos (93.7%) habían estado en terapia biológica en el preoperatorio, y la mayoría reanudó la misma terapia biológica (68%). La mediana de tiempo para comenzar la terapia biológica después de la operación fue de 31 días (rango, 7-89 días). La exposición biológica postoperatoria no se asoció con un mayor riesgo de infección superficial del sitio quirúrgico (HR 1.02 (0.95-1.09) por semana, p = 0.59), sepsis intraabdominal. (HR: 1.07 (0.99-1.16), p = 0.73), o complicaciones infecciosas postoperatorias generales (HR: 1.02, intervalo de confianza del 95% 0.98-1.07, p = 0.338); las tasas generales de cada uno a los 90 días fue del 13%, 8% y 28%. LIMITACIONES: Diseño retrospectivo, y datos de un centro único. CONCLUSIONES: El inicio o la reanudación en el postoperatorio de la terapia biológica no aumentaron las tasas a 90 días de infección superficial de sitio quirúrgico, sepsis intraabdominal o complicaciones infecciosas totales después de una cirugía abdominal mayor por enfermedad de Crohn. Consulte el Video Resumen en http://links.lww.com/DCR/B207. (Traducción—Dr Jorge Silva Velazco)