Inflammatory bowel disease
BioMG follows French guidelines. Adapt it to the guidelines and the tests available where you practise.
Initial tests
Fasting laboratory tests
- FBC
- CRP
- Serum electrolytes
- Serum albumin
- Serum creatinine with eGFR
- Serum ferritin
- Transferrin saturation
- Vitamin B9 (folate)
- Vitamin B12
- Liver function tests (AST, ALT, GGT, ALP, bilirubin)if neededAt diagnosis of UC: the French recommendation includes liver function tests in the initial tests [3].
- 25-hydroxyvitamin Dif neededAt diagnosis of UC: measurement recommended by the French recommendation [3].
- Hepatitis B serology (HBsAg, anti-HBs antibodies, anti-HBc antibodies)if needednon-French guidelineAt diagnosis, routine according to ECCO: hepatitis B screening and vaccination if needed, before any immunosuppressant. [4]
- Hepatitis C serologyif neededAt diagnosis of IBD: serology recommended in the initial tests (ECCO-ESGAR 2019, according to the French synthesis [4]).
- HIV serologyif neededAt diagnosis of IBD: serology recommended in the initial tests (ECCO-ESGAR 2019, according to the French synthesis [4]).
- Measles serologyif neededAt diagnosis, before any immunosuppressive treatment: measles and varicella vaccines are live, hence contraindicated afterwards.
- Varicella serologyif neededAt diagnosis, before any immunosuppressive treatment: measles and varicella vaccines are live, hence contraindicated afterwards.
- EBV serologyif neededAt diagnosis of IBD: serology recommended in the initial tests (ECCO-ESGAR 2019, according to the French synthesis [4]).
- CMV serologyif neededAt diagnosis of IBD: serology recommended in the initial tests (ECCO-ESGAR 2019, according to the French synthesis [4]).
- QuantiFERONif neededScreening for latent tuberculosis: requested from diagnosis by the French recommendation on Crohn's disease [5]; not provided for by the ECCO consensus [4]. Reimbursed (code 4103) before starting an anti-TNF or an anti-JAK; outside these situations, outside the NABM indications [6].
Stool tests
- Stool culture
- Faecal calprotectin (if doubt between inflammatory bowel disease and functional disorder)if neededSuspected IBD, especially to distinguish IBD from a functional disorder: the synthesis of the ECCO consensus places it in the initial tests [4], whereas the French recommendations on Crohn's disease and ulcerative colitis propose it "possibly" with FBC and CRP [3,5]; a low CRP together with a low calprotectin has a negative predictive value of 99% for Crohn's disease [5]. At diagnosis, it is not reimbursed (code 1684 requires already known IBD) [6], and in 2020 HAS did not reach a consensus judgement on its diagnostic value [7].
- Clostridioides difficile testing (if diarrhoea)if neededSuspected IBD: the first step is to exclude intestinal infection, with stool culture and C. difficile toxin testing as routine [4]; code 1033 reimbursed in a patient over 3 years of age with diarrhoea [6].
- Stool parasitology, to be done 3 times (if stay in an endemic area)if neededRecommended after recent travel to a parasite-endemic area [3,5].
Also consider
- Biologic or JAK inhibitor planned? Before a biologic or a JAK inhibitor, see the page "Biologic or JAK inhibitor: tests before treatment and monitoring".
- Azathioprine planned? Before azathioprine, see the "Pharmacogenetics" page for TPMT.
Do not order
Monitoring
Stool tests
- Faecal calprotectin
Laboratory tests
- CRP
Sources (19)
- Sarter H, Crétin T, Savoye G, et al. Incidence, prevalence and clinical presentation of inflammatory bowel diseases in Northern France: a 30-year population-based study. Lancet Reg Health Eur 2024;47:101097.
- LES MICI EN FRANCE
- Amiot A, Viennot S, Uzzan M, et al. Recommandations de pratique pour le diagnostic et la prise en charge de la rectocolite hémorragique (version longue), GETAID. Hepato Gastro Oncol Dig 2022;29:e297-e351.
- Diagnostic initial, suivi des MICI et détection des complications
- Bouguen G, Gornet JM, Hamoudi N, et al. Recommandations françaises pour la prise en charge de la maladie de Crohn, version longue. GETAID, avril 2024 (Hepatogastroenterol Oncol Dig 2024;31:1-52).
- Assurance maladie. Nomenclature des actes de biologie médicale (NABM), version 105 : actes 1684 (calprotectine fécale), 4103 (IGRA), 1804 (CRP), 1033 (Clostridioides difficile).
- Haute Autorité de santé. Intérêt du dosage de calprotectine fécale pour le diagnostic étiologique de troubles digestifs chroniques survenant chez des sujets de moins de 50 ans sans signe d'alarme ni élévation de la CRP. Rapport d'évaluation, mai 2020.
- Haute Autorité de santé. Actes et prestations – affection de longue durée n° 24 : maladie de Crohn. Mise à jour mai 2019.
- Haute Autorité de santé. Actes et prestations – affection de longue durée n° 24 : rectocolite hémorragique évolutive. Mise à jour mai 2019.
- ANSM, Base de données publique des médicaments. Résumé des caractéristiques du produit IMUREL 50 mg (azathioprine), rubriques 4.2 et 4.4, consulté le 13 octobre 2026.
- Institut national d'excellence en santé et en services sociaux (INESSS, Québec). Dosage de la calprotectine fécale. Avis d'évaluation (réf. 2013-03-005), avis transmis au ministre le 28 février 2014.
- Lichtenstein GR, Loftus EV, Afzali A, Long MD, Barnes EL, Isaacs KL, Ha CY. ACG Clinical Guideline: Management of Crohn's Disease in Adults. Am J Gastroenterol 2025;120(6):1225-1264.
- Rubin DT, Ananthakrishnan AN, Siegel CA, Barnes EL, Long MD. ACG Clinical Guideline Update: Ulcerative Colitis in Adults. Am J Gastroenterol 2025;120(6):1187-1224.
- National Institute for Health and Care Excellence. Faecal calprotectin diagnostic tests for inflammatory diseases of the bowel. HealthTech guidance HTG320 (ex-diagnostics guidance DG11), publiée le 2 octobre 2013, texte inchangé.
- Nakase H, Uchino M, Shinzaki S, et al. Evidence-based clinical practice guidelines for inflammatory bowel disease 2020 (Japanese Society of Gastroenterology). J Gastroenterol 2021;56(6):489-526.
- Belgique, SPF Sécurité sociale. Arrêté royal du 18 juin 2017 modifiant l'article 24, § 1er, de la nomenclature des prestations de santé (dosage de la calprotectine, prestations 544751-544762, règle diagnostique 122). Moniteur belge, 13 juillet 2017, p. 72418.
- Ananthakrishnan AN, Adler J, Chachu KA, et al. AGA Clinical Practice Guideline on the Role of Biomarkers for the Management of Crohn's Disease. Gastroenterology 2023;165(6):1367-1399.
- Butler TD, Segal JP. Guideline review: 2025 British Society of Gastroenterology guidelines on inflammatory bowel disease in adults - Part 2: ulcerative colitis. Frontline Gastroenterol 2025 (doi 10.1136/flgastro-2025-103426). Revue de la recommandation BSG 2025 (Moran GW et al., Gut 2025;74(Suppl 2):s1-s101), dont le texte n'a pas pu être lu.
- ECCO-ESGAR Guideline for Diagnostic Assessment in IBD Part 1: Initial diagnosis, monitoring of known IBD, detection of complications (ECCO 2019). Maaser C, Sturm A, Vavricka SR, et al. J Crohns Colitis. 2019;13(2):144-164.