Validation of the Red Flags Index for Early Diagnosis of Crohn’s Disease: A Prospective Observational IG-IBD Study Among General Practitioners

Gionata Fiorino, Stefanos Bonovas, Daniela Gilardi, Antonio Di Sabatino, Mariangela Allocca, Federica Furfaro, Giulia Roda, Marco V Lenti, Nicola Aronico, Caterina Mengoli, Enzo Angeli, Nicola Gaffuri, Laurent Peyrin-Biroulet, Silvio Danese

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Diagnostic delay \gt;12 months is frequent in Crohn’s disease [CD]. Recently, the International Organization for Inflammatory Bowel Disease [IO-IBD] developed a tool to identify early CD and reduce diagnostic delay. Subjects with an index ≥8 are more likely to have suspected CD (odds ratio [OR] 205, p \lt;0.0001). We aimed to validate this questionnaire at the community level in patients seen by the general practitioners [GPs] in two large areas of Lombardy, Italy.Consecutive adult patients referring to the GP were screened. The GPs administered the Red Flags [RF] questionnaire to the eligible patients. All patients were referred to the nearest participating centre to confirm or exclude the diagnosis of CD. Sensitivity, specificity, and positive and negative predictive values [PPV, NPV] of the RF index [RFI] were calculated. Patients lost to follow-up after the first gastroenterological visit were analysed using a non-responder imputation, assuming they were negative for CD diagnosis.From November 2016 to November 2019, 112 patients were included. A total of 66 subjects [59\ completed the study after the first gastroenterological visit. The prevalence of CD was 3.6\4/112]. The RF index had 50\ 58\ 4\ and 97\FC] [RFI ≥8 and/or FC \gt;250 ng/g] resulted in significantly improved accuracy: sensitivity 100\29–100\, specificity 72\55–85\, PPV = 21\5–51\, NPV = 100\88–100\.The RF Index combined with FC is a valid tool to identify patients with high probability of having CD at early stage.
Original languageUndefined/Unknown
Pages (from-to)1777-1779
Number of pages3
JournalJournal of Crohn's and Colitis
Issue number12
Publication statusPublished - Sep 1 2020

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