Diagnostic Value of Ileal Biopsies in Patients with Suspected Crohn’s Disease

Aim: to analyze both consultative and current diagnostic biopsy materials to determine the diagnostic value of ileal biopsies and the possible spectrum of morphological changes observed in patients with suspected Crohn’s disease.  

Materials and methods. We analyzed the results of ileal biopsy examinations (n = 202) received at the centralized pathological anatomy department of the Clinical Center of Sechenov University from 2022 to 2024, performed both for current diagnostics and for consultations on pre-prepared histological slides. During this period, 568 ileal biopsies from 154 patients were examined, and an additional 200 pre-prepared histological slides from 48 consultative patients were reviewed.

Results. Among the examined ileal biopsies, a histological variant of normal tissue was confirmed in 97 patients, focal active ileitis was identified in 42 cases, and chronic active ileitis — in 63 cases. Chronic active ileitis with morphological changes highly suspicious for Crohn’s disease was found in 47 (23 %) cases. These findings suggest that the likelihood of diagnosing Crohn’s disease based on ileal biopsy results remains low.

Conclusions. Diagnosing chronic ileitis requires pathologists to identify reliable signs of chronicity. In addition to structural remodeling and plasma cell infiltration, which are not always easily recognizable in unoriented biopsies and have poor interobserver reproducibility, key indicators include pseudopyloric metaplasia, hypersecretion, microgranulomas, and epithelioid granulomas. The identification of these changes strongly supports the diagnosis of regional ileitis in Crohn’s disease. However, the final interpretation of these findings must be made in the context of clinical information and corroborative imaging data.

1. D’Amico F., Gomollón F., Bamias G., Magro F., Targownik L., Leitner C., et al. Proportion of inflammatory bowel diseases patients with suboptimal disease control in daily clinical practice — Real-world evidence from the inflammatory bowel diseases-podcast study. United European Gastroenterol J. 2024;12(6):705–16. DOI: 10.1002/ueg2.12572

2. Selivanova L.S., Sharoyan Zh.V., Tertychnyy A.S. Morphological characteristics of biopsy material from the ileum: Features in normal conditions and inflammatory bowel diseases. Bulletin of the N.I. Pirogov National Medical and Surgical Center. 2015;10(2):90–3. (In Russ.).

3. Tertych-nyy A.S., Akhriyeva Kh.M., Kogan E.A., Zayratyants O.V., Selivanova L.S. Modern approaches in the morphological diagnosis of inflammatory bowel diseases. Russian Journal of Gastroenterology, Hepatology, Coloproctology. 2022;32(2):73–84. (In Russ.). DOI: 10.22416/1382-4376-2022-32-2-73-84

4. Gordon H., Biancone L., Fiorino G., Katsanos K.H., Kopylov U., Al Sulais E., et al. ECCO guidelines on inflammatory bowel disease and malignancies. J Crohns Colitis. 2023;17(6):827–54. DOI: 10.1093/ecco-jcc/jjac187

5. Grinman A., Ungar B., Lahat A., Kopylov U., Eliakim R., Ben-Horin S. Incidentally diagnosed asymptomatic Crohn’s disease: A retrospective cohort study of long-term clinical outcomes. Crohns Colitis 360. 2022;4(3):otac034. DOI: 10.1093/crocol/otac034

6. Agrawal M., Miranda M.B., Walsh S., Narula N., Colombel J.F., Ungaro R.C. Prevalence and progression of incidental terminal ileitis on non-diagnostic colonoscopy: A systematic review and meta-analysis. J Crohns Colitis. 2021;15(9):1455–63. DOI: 10.1093/ecco-jcc/jjab030

7. Koureta E., Karatzas P., Tampaki M., Voulgaris T., Laoudi E., Sakellariou S., et al. Isolated nonspecific terminal ileitis: Prevalence, clinical evolution and correlation with metachronous diagnosis of Crohn’s disease: A retrospective study and review of the literature. Ann Gastroenterol. 2024;37(2):199–205. DOI: 10.20524/aog.2024.0863

8. Kim D.S., Ryu J.E., Shin J., Koo H.S., Lee S., Cho H., et al. Diagnostic value of ileal lesions found during colonoscopy with reference to endoscopic indications and findings. J Clin Med. 2024;13(4):1161. DOI: 10.3390/jcm13041161

9. Tertychnyi A.S., Akhrieva Kh.M., Maev I.V., Zayratyants O.V., Selivanova L.S. Diagnostic problems of histological remission in patients with inflammatory bowel disease. Russian Journal of Archive of Pathology. 2017;79(3):3–9. (In Russ.). DOI: 10.17116/patol20177933-9

10. Kotla N.G., Rochev Y. IBD disease-modifying therapies: Insights from emerging therapeutics. Trends Mol Med. 2023;29(3):241–53. DOI: 10.1016/j.molmed.2023.01.001

11. McHugh J.B., Appelman H.D., McKenna B.J. The diagnostic value of endoscopic terminal ileum biopsies. Am J Gastroenterol. 2007;102(5):1084–9. DOI: 10.1111/j.1572-0241.2007.01194.x

12. Feakins R., Borralho Nunes P., Driessen A., Gordon I.O., Zidar N., Baldin P., et al. Definitions of histological abnormalities in inflammatory bowel disease: An ECCO position paper. J Crohns Colitis. 2024;18(2):175–91. DOI: 10.1093/ecco-jcc/jjad142

13. Villanacci V., Reggiani-Bonetti L., Caprioli F., Saragoni L., Salviato T., Mescoli C., et al. Histopathology of inflammatory bowel disease — Position statement of the pathologists of the Italian Group for the Study of Inflammatory Bowel Disease (IG-IBD) and Italian Group of Gastrointestinal Pathologists (GIPAD-SIAPEC). Dig Liver Dis. 2020;52(3):262–7. DOI: 10.1016/j.dld.2019.11.005