title: Development of the Lémann index to assess digestive tract damage in patients with Crohn's disease.
abstract: OBJECTIVE
  There is a need for a scoring system that provides a comprehensive assessment of structural bowel damage, including stricturing lesions, penetrating lesions, and surgical resection, for measuring disease progression. We developed the Lémann Index and assessed its ability to measure cumulative structural bowel damage in patients with Crohn's disease (CD).
  
  
  METHODS
  We performed a prospective, multicenter, international, cross-sectional study of patients with CD evaluated at 24 centers in 15 countries. Inclusions were stratified based on CD location and duration. All patients underwent clinical examination and abdominal magnetic resonance imaging analyses. Upper endoscopy, colonoscopy, and pelvic magnetic resonance imaging analyses were performed according to suspected disease locations. The digestive tract was divided into 4 organs and subsequently into segments. For each segment, investigators collected information on previous operations, predefined strictures, and/or penetrating lesions of maximal severity (grades 1-3), and then provided damage evaluations ranging from 0.0 (no lesion) to 10.0 (complete resection). Overall level of organ damage was calculated from the average of segmental damage. Investigators provided a global damage evaluation (from 0.0 to 10.0) using calculated organ damage evaluations. Predicted organ indexes and Lémann Index were constructed using a multiple linear mixed model, showing the best fit with investigator organ and global damage evaluations, respectively. An internal cross-validation was performed using bootstrap methods.
  
  
  RESULTS
  Data from 138 patients (24, 115, 92, and 59 with upper tract, small bowel, colon/rectum, and anus CD location, respectively) were analyzed. According to validation, the unbiased correlation coefficients between predicted indexes and investigator damage evaluations were 0.85, 0.98, 0.90, 0.82 for upper tract, small bowel, colon/rectum, anus, respectively, and 0.84 overall.
  
  
  CONCLUSIONS
  In a cross-sectional study, we assessed the ability of the Lémann Index to measure cumulative structural bowel damage in patients with CD. Provided further successful validation and good sensitivity to change, the index should be used to evaluate progression of CD and efficacy of treatment.
authors.affiliation: Department of Hepatogastroenterology, Hôpital Saint-Louis, Paris, France; Department of Hepatogastroenterology, University of Lille, Hôpital Claude Huriez, Lille, France.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Pariente
authors.affiliation: INSERM U717, Biostatistics and Clinical Epidemiology, Hôpital Saint-Louis, Paris, France.
authors.forename: Jean-Yves
authors.initials: JY
authors.lastname: Mary
authors.affiliation: BD Center, Department of Gastroenterology, Istituto Clinico Humanitas, Rozzano, Milan, Italy.
authors.forename: Silvio
authors.initials: S
authors.lastname: Danese
authors.affiliation: Department of Gastroenterology, Rambam Health Care Campus, Haifa, Bat Galim, Israel.
authors.forename: Yehuda
authors.initials: Y
authors.lastname: Chowers
authors.affiliation: St Vincent's Hospital & University of Melbourne, Melbourne, Australia.
authors.forename: Peter
authors.initials: P
authors.lastname: De Cruz
authors.affiliation: Academic Medical Center, Amsterdam, The Netherlands; Imelda GI Clinical Research Center, Bonheiden, Belgium.
authors.forename: Geert
authors.initials: G
authors.lastname: D'Haens
authors.affiliation: Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota.
authors.forename: Edward V
authors.initials: EV
authors.lastname: Loftus
authors.affiliation: Department of Hepatogastroenterology, Centre Hospitalier Universitaire de Liège, Liège University, Liège, Belgium.
authors.forename: Edouard
authors.initials: E
authors.lastname: Louis
authors.affiliation: Gastroenterology Department, Hospital Clinic of Barcelona, IDIBAPS, CIBERehd, Barcelona, Spain.
authors.forename: Julian
authors.initials: J
authors.lastname: Panés
authors.affiliation: Department of Internal Medicine I, University of Regensburg, Regensburg, Germany.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Schölmerich
authors.affiliation: Institute of Clinical Molecular Biology, Christian-Albrechts University, Kiel, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Schreiber
authors.affiliation: Gastroenterology and Gastrointestinal Endoscopy Unit, IRCCS Policlinico San Donato and University of Milan, Milan, Italy.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Vecchi
authors.affiliation: Department of Hepatogastroenterology, University of Lille, Hôpital Claude Huriez, Lille, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Branche
authors.affiliation: Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota.
authors.forename: David
authors.initials: D
authors.lastname: Bruining
authors.affiliation: BD Center, Department of Gastroenterology, Istituto Clinico Humanitas, Rozzano, Milan, Italy.
authors.forename: Gionata
authors.initials: G
authors.lastname: Fiorino
authors.affiliation: Institute of Clinical Molecular Biology, Christian-Albrechts University, Kiel, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Herzog
authors.affiliation: St Vincent's Hospital & University of Melbourne, Melbourne, Australia; Imperial College, London, UK.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Kamm
authors.affiliation: Department of Gastroenterology, Rambam Health Care Campus, Haifa, Bat Galim, Israel.
authors.forename: Amir
authors.initials: A
authors.lastname: Klein
authors.affiliation: Radiology Department, Hôpital Saint-Antoine, Paris, France.
authors.forename: Maïté
authors.initials: M
authors.lastname: Lewin
authors.affiliation: Department of Medical Imaging, Centre Hospitalier Universitaire de Liège, Liège University, Liège, Belgium.
authors.forename: Paul
authors.initials: P
authors.lastname: Meunier
authors.affiliation: Gastroenterology Department, Hospital Clinic of Barcelona, IDIBAPS, CIBERehd, Barcelona, Spain.
authors.forename: Ingrid
authors.initials: I
authors.lastname: Ordas
authors.affiliation: Department of Internal Medicine I, University of Regensburg, Regensburg, Germany.
authors.forename: Ulrike
authors.initials: U
authors.lastname: Strauch
authors.affiliation: Gastroenterology and Gastrointestinal Endoscopy Unit, IRCCS Policlinico San Donato and University of Milan, Milan, Italy.
authors.forename: Gian-Eugenio
authors.initials: GE
authors.lastname: Tontini
authors.affiliation: Radiology Department, Hôpital Saint-Louis, Paris, France.
authors.forename: Anne-Marie
authors.initials: AM
authors.lastname: Zagdanski
authors.affiliation: Department of Radiology, Istituto Clinico Humanitas, Rozzano, Milan, Italy.
authors.forename: Cristiana
authors.initials: C
authors.lastname: Bonifacio
authors.affiliation: Radiology Department, CDI-Hospital Clinic, Barcelona, Spain.
authors.forename: Jordi
authors.initials: J
authors.lastname: Rimola
authors.affiliation: Department of Hepatogastroenterology, University of Lille, Hôpital Claude Huriez, Lille, France.
authors.forename: Maria
authors.initials: M
authors.lastname: Nachury
authors.affiliation: Radiology Department, University Hospital, Lille, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Leroy
authors.affiliation: Division of Gastroenterology, UC San Diego Health System, La Jolla, California.
authors.forename: William
authors.initials: W
authors.lastname: Sandborn
authors.affiliation: Department of Gastroenterology, Icahn Medical School at Mount Sinai, New York, New York.
authors.forename: Jean-Frédéric
authors.initials: JF
authors.lastname: Colombel
authors.affiliation: Gastroenterology and Nutrition Department, Hôpital Saint-Antoine, Paris, France. Electronic address: jacques.cosnes@sat.ap-hop-paris.fr.
authors.forename: Jacques
authors.initials: J
authors.lastname: Cosnes
mesh_terms: D000328:Adult; D001315:Australia; D003113:Colonoscopy; D003424:Crohn Disease / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D003430:Cross-Sectional Studies; D003952:Diagnostic Imaging / Q000379:methods; D005060:Europe; D005260:Female; D041981:Gastrointestinal Tract / Q000000981:diagnostic imaging / Q000473:pathology*; D006801:Humans; D007557:Israel; D016014:Linear Models; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D015588:Observer Variation; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed
keywords: Illness Index Severity; MRI; Prognosis; Response to Therapy