531: Multimodal Pain Management in a Young Adult with Fistulizing Crohn�s Disease: A Case Report

Topic: Clinical Science
Subtopic: Pain category (ICD-11), Chronic neuropathic pain, Pharmacological treatments, Non-pharmacological treatments, Pain in special populations (e.g. neonates, children, teens, elderly, neurodegenerative diseases)

Background and Aims: Crohn’s disease (CD) is a chronic, idiopathic inflammatory bowel disease defined by transmural inflammation, which frequently penetrates the bowel wall leading to fibrotic strictures, fistulas, and abscesses. This case report details the multidisciplinary management of a 19-year-old male with a longstanding history of Crohn's disease who presented with severe abdominal pain, fever, and an active perianal enterocutaneous fistula.This case demonstrates the structural progression of the disease, necessitating an escalation in therapy from first-line mesalamine to a multimodal treatment strategy. This contemporary approach included necessary surgical source control (incision and drainage with Seton placement), targeted biologic therapy (vedolizumab), and a highly structured opioid-tapering pain management strategy utilizing scheduled paracetamol and gabapentinoids (pregabalin) to address severe visceral and neuropathic pain.

Methods: A 19-year-old male with a diagnosed case of fistulizing Crohn's disease was admitted to the hospital due to abdominal pain and fever, necessitating surgical evaluation and management of a perianal abscess.
The patient's clinical history dates back 11 years (at age 8) when he was initially admitted for a perianal abscess, which was managed with an incision and drainage (I&D) and subsequently healed. Ten years ago, at age 9, he experienced frequent episodes of abdominal pain, diarrhea, and weight loss. Subsequent endoscopy and colonoscopy noted gastric ulcers and chronic atrophic gastritis. He was formally diagnosed with Crohn's disease and managed with mesalamine for an unrecalled period of time. In the interim years, the patient noted poor wound healing at the site of his previous perianal abscess, which progressively developed into a fistula with continuous leakage of yellowish stool.

Results: Surgical intervention was required, and the patient underwent an I&D of the abscess with the placement of a Seton. Concurrently, his medical management was escalated with the initiation of vedolizumab, a humanized monoclonal antibody used to treat moderate-to-severe Crohn’s disease. Over the course of the admission, the pain management team gradually decreased the morphine while increasing the pregabalin dose and adding scheduled paracetamol to achieve better, opioid-sparing pain control.
After a 2-week hospital stay, the patient was in good pain control and successfully discharged. He was sent home on a structured medication regimen including a Morphine sulfate tablet every 6 hours, Fentanyl sublingual tablet as a rescue dose, added paracetamol, and pregabalin increased to 75 mg three times a day. His outpatient transition plan involves subsequently decreasing the opioid load and shifting down to tramadol.

Conclusions: The modern management of complex fistulizing Crohn's disease extends far beyond simple symptomatic control or isolated surgical intervention. It requires a coordinated, multidisciplinary strategy. This includes the targeted biologic therapy (vedolizumab) and timely surgical source control for penetrating complications. Crucially, integrating aggressive, multimodal pain management, particularly utilizing scheduled non-opioids and gabapentinoids to actively taper down opioid reliance, ensures patient safety, prevents narcotic dependency, and significantly improves functional recovery during severe acute exacerbations.

References: Angriman, I., Tomassi, M., Ruffolo, C., et al. (2022). Impact on quality of life of seton placing in perianal Crohn's disease. Frontiers in Surgery, 8. https://doi.org/10.3389/fsurg.2021.806497
Ayoub, F., Odenwald, M., Micic, D., et al. (2022). Vedolizumab for perianal fistulizing Crohn’s disease: Systematic review and meta-analysis. Intestinal Research, 20, 240–250. https://doi.org/10.5217/ir.2021.00091
Baillie, S., Norton, C., Saxena, S., & Pollok, R. (2024). Chronic abdominal pain in inflammatory bowel disease: A practical guide. Frontline Gastroenterology, 15(2), 144–153. https://doi.org/10.1136/flgastro-2023-102471
Casanova, M. J., Caballol, B., García, M. J., et al. (2024). Persistence, effectiveness and safety of ustekinumab and vedolizumab therapy for complex perianal fistula in Crohn's disease: The HEAL study from GETECCU. Digestive and Liver Disease, 56, 1845–1853. https://doi.org/10.1016/j.dld.2024.05.009
Common pathways in Crohn's disease and other inflammatory diseases revealed by genomics. (n.d.).
Comparison between fecal calprotectin and magnetic resonance enterography in ileal Crohn's disease for activity disease assessment: A systematic review. (n.d.). ResearchGate.
Feagan, B. G., Schwartz, D., Danese, S., et al. (2018). Efficacy of vedolizumab in fistulising Crohn’s disease: Exploratory analyses of data from GEMINI 2. Journal of Crohn's and Colitis, 12, 621–626. https://doi.org/10.1093/ecco-jcc/jjy019
Haennig, A., Staumont, G., Lepage, B., et al. (2015). The results of seton drainage combined with anti‐TNFα therapy for anal fistula in Crohn's disease. Colorectal Disease, 17, 311–319. https://doi.org/10.1111/codi.12851
Hoilat, G. J., Menon, G., & Rentea, R. M. (2023). Crohn disease stricturoplasty. In StatPearls. StatPearls Publishing.
Hukkinen, M., Pakarinen, M. P., Piekkala, M., et al. (2014). Treatment of complex perianal fistulas with seton and infliximab in adolescents with Crohn's disease. Journal of Crohn's and Colitis, 8, 756–762. https://doi.org/10.1016/j.crohns.2014.01.001
Ismail, M. S., & Charabaty, A. (2022). Management of Crohn's stricture: Medical, endoscopic and surgical therapies. Frontline Gastroenterology, 13(6), 524–530. https://doi.org/10.1136/flgastro-2021-101827
Lavoie, S., Conway, K. L., Lassen, K. G., Jijon, H. B., Pan, H., Chun, E., ... & Xavier, R. J. (2019). The Crohn's disease polymorphism, ATG16L1 T300A, alters the gut microbiota and enhances the local Th1/Th17 response. eLife, 8, e39982. https://doi.org/10.7554/eLife.39982
Lewis, J. D., Sandler, R. S., Brotherton, C., Brensinger, C., Li, H., Kappelman, M. D., ... & Herfarth, H. (2021). Comparing two diets to decrease symptoms from Crohn's disease – The DINE-CD study. Patient-Centered Outcomes Research Institute (PCORI). https://doi.org/10.25302/10.2021.PPRND.150731465
Luglio, G., Cricrì, M., Tropeano, F. P., & De Palma, G. D. (2023). Crohn's disease: Is minimally invasive surgery the gold standard? A narrative review. Annals of Laparoscopic and Endoscopic Surgery, 8, 21. https://doi.org/10.21037/ales-22-75
Meerschaert, K. A., & Chiu, I. M. (2024). The gut–brain axis and pain signalling mechanisms in the gastrointestinal tract. Nature Reviews Gastroenterology & Hepatology. https://doi.org/10.1038/s41575-024-01017-9
Melmed, G., Patel, D., Govalan, R., Huang, S. G., Bresee, C., & Nuckols, T. K. (2024, February 19). Novel pain management protocol reduces opioid use in hospitalized IBD patients. Cedars-Sinai.
Pathophysiological mechanisms, clinical management, and therapeutic evolution of Crohn's disease: A comprehensive analysis. (n.d.).
Ramos, G. P., & Papadakis, K. A. (2019). Mechanisms of disease: Inflammatory bowel diseases. Mayo Clinic Proceedings, 94(1), 155–165. https://doi.org/10.1016/j.mayocp.2018.09.013
Ribeiro da Silva, R. A. V., Genaro, L. M., Lahan-Martins, D., Leal, R. F., & Ayrizono, M. L. S. (2025). Comparison between fecal calprotectin and magnetic resonance enterography in ileal Crohn's disease for activity disease assessment: A systematic review. Translational Gastroenterology and Hepatology, 10, 73. https://doi.org/10.21037/tgh-24-159
Vaid, R., Fareed, A., Qader, R., Hussain, A., Shaikh, W., Zameer, U., & Ochani, S. (2025). Cannabis use in Crohn's disease: A systematic review and meta-analysis of randomized controlled trials (RCTs). Irish Journal of Medical Science, 194(2), 439-446. https://doi.org/10.1007/s11845-024-03844-w
Wang, H., Ding, J., Liu, G., Sun, G., Zhang, X., Xiao, W., Cai, Y., & Lin, A. (2025). Efficacy of different psychological interventions for the treatment of inflammatory bowel disease: A systematic review and network meta-analysis. Frontiers in Medicine, 12, 1630034. https://doi.org/10.3389/fmed.2025.1630034
Wasmann, K., de Groof, E. J., Stellingwerf, M. E., et al. (2019). Treatment of perianal fistulas in Crohn's disease, seton versus anti-TNF versus surgical closure following anti-TNF (PISA): A randomised controlled trial. SSRN Electronic Journal. https://doi.org/10.2139/ssrn.3356856
White, I., Karki, C., Geransar, P., et al. (2024). Impact of seton use on clinical, patient-reported, and healthcare resource utilization outcomes in complex Crohn’s perianal fistulas: A systematic literature review. Inflammatory Bowel Diseases. https://doi.org/10.1093/ibd/izae186
Zhai, M. Z., & Dalal, R. S. (2025). Updated 2025 ACG clinical guideline for the management of Crohn's disease. Evidence-Based GI.

Presenting Author: Jo Mari Darvin Carnaje Adorador, MD, DPBA
Submitting Author: Jo Mari Darvin Adorador

Senior Author: Maria Elena Basco-Tiamson, MD, FPSA, DPBPM

IASP 2026 Global Year theme of Neuropathic Pain: Yes