Cyclophosphamide Pulse Therapy in Severe Refractory Crohn's Disease: A Retrospective Multicenter Case Series

Exploration of the potential causative genes for inflammatory bowel disease: Transcriptome-wide association analysis, Mendelian randomization analysis and Bayesian colocalisation

Background

Inflammatory bowel disease (IBD) poses a complex challenge due to its intricate underlying mechanisms, and curative treatments remain elusive. Consequently, there is an urgent need to identify genes causally associated with IBD.

Methods

We extracted blood eQTL data from the GTExv8.ALL.Whole_Blood database, genome-wide association studies (GWAS) summary statistics of IBD from the IEU GWAS database, and performed a three-fold analysis protocol, including transcriptome-wide association analysis, Mendelian randomisation analysis, Bayesian colocalisation, and subsequent potential therapeutic agents identification.

Results

We identified four pathogenic genes, namely CARD9, RTEL1, STMN3 and ARFRP1, that promote the development of IBD, encompassing both ulcerative colitis (UC) and Crohn's disease (CD). Notably, ARFRP1 exhibited the ability to suppress IBD (encompassing UC and CD) development. Regarding drug prediction, cyclophosphamide emerged as a promising novel therapeutic option for IBD, encompassing UC and CD.

Conclusion

We identified several potential genes related to IBD (UC and CD), including CARD9, RTEL1, STMN3 and ARFRP1, warranting further investigation in functional studies to elucidate underlying disease mechanisms. Additionally, clinical studies exploring the potential of cyclophosphamide as a treatment avenue for IBD are warranted.

Management of refractory inflammatory bowel disease

PURPOSE OF REVIEW

Nearly one-third of patients with inflammatory bowel disease (IBD) do not achieve remission despite our best therapies. When this happens, it is critical to understand the reason for treatment failure. Once nonresponse is confirmed, these patients should be referred to an IBD centre for multidisciplinary care. This review will discuss the remaining treatment options, including escalation of biologics to unlicensed doses, combination biologics, nonvalidated therapies and surgical options. It will additionally provide updates in the management of acute severe ulcerative colitis (ASUC).

RECENT FINDINGS

There is an increasing interest in combination biologics to treat refractory IBD, although data supporting its safety and effectiveness are limited. The use of hyperbaric oxygen, mesenchymal stem cell therapy and dietary interventions also show early promise in this area. Studies have additionally focused on personalized therapy to identify aggressive phenotypes and predict treatment response in these challenging patients. In ASUC, infliximab and cyclosporine remain mainstays of treatment, and tofacitinib shows promise as a salvage therapy.

SUMMARY

Refractory IBD is common, yet large knowledge gaps remain. Recent and ongoing studies have focused on medical, surgical and dietary approaches with mixed success. Larger prospective studies are desperately needed to address this complex issue.