Risk Factors for Developing Hidradenitis Suppurativa in Patients With Inflammatory Bowel Disease: A Retrospective Case-Control Study

Causal association between inflammatory bowel disease and hidradenitis suppurativa: A two-sample bidirectional Mendelian randomization study

Background

Epidemiological studies have revealed a link between inflammatory bowel disease (IBD) and hidradenitis suppurativa (HS). To determine whether IBD and HS are causally related, we used the Mendelian randomization (MR) approach.

Methods

A two-sample MR was performed using an analysis of 12,882 patients and 21,770 controls with IBD and its main subtypes, ulcerative colitis (UC) and Crohn's disease (CD). A total of 409 cases and 211,139 controls without hidradenitis suppurativa (HS) were included in the data for this condition from various GWAS investigations. Odds ratios (ORs) with 95% confidence intervals (CIs) are used to estimate causal effects.

Results

The study assessed the causal relationship between HS and IBD in both directions. The risk of HS was increased by IBD (IVW OR = 1.34, 95% CI = 1.20-1.49, p = 2.15E-07) and, in addition, HS was affected by UC (IVW OR = 1.27, 95% CI = 1.13-1.43, p = 8.97E-04) and CD (IVW OR = 1.18, 95% CI = 1.08-1.29, p = 4.15E-04). However, there was no evidence of a causal relationship between HS and IBD or its subtypes (IBD IVW OR = 1.00, 95% CI = 0.96-1.05, p = 0.85; UC IVW OR = 0.99, 95% CI = 0.95-1.03, p = 0.65; CD IVW OR = 1.03, 95% CI = 0.98- 1.07, p = 0.28).

Conclusion

This study demonstrates that IBD and its subtypes have a causal effect on HS, whereas HS does not affect IBD. Gut-skin axis interactions may help to understand this association. Nevertheless, further studies are needed to clarify the pathophysiology of the causal relationship between IBD and HS.

Bone Marrow Mesenchymal Stem Cells (BMSC) Carried with miR-338 Improve BMSC Homing in Intestinal Mucosa of Inflammatory Bowel Disease (IBD) Rats Through Increasing C-X-C Chemokine Receptor Type 4 (CXCR-4)

This study assessed whether bone marrow mesenchymal stem cells (BMSC) carried with miR-338 improve its homing in intestinal mucosa of IBD rats. Fifty SD rats were equally and randomly assigned into control set, model set, miR-338 set, CXCR-4 Inhibitor set and positive control set followed by analysis of miR-338 expression, body weight, DAI grade, pathological changes of distal colonic tissue, ultra-microstructure of intestinal epithelium, level of IL-8, IL-10, TGF-β1, VEGF, and CXCR4, as well as the relation between miR-338 and CXCR-4. miR-338 in decorated BMSC was significantly upregulated. Body weight in model set and CXCR-4 Inhibitor set was lowest followed by miR-338 set and positive control set. However, opposite results were obtained for DAI grade. IL-8 level was highest and IL-10 was lowest in model set and CXCR-4 Inhibitor set. The BMSC carried with miR-338 exerted recovery action on the intestinal mucosa of IBD rats and inhibited the activity of inflammatory cells. In conclusion, BMSC carried with miR-338 develops recovery action on the intestinal mucosa of IBD rats possibly through regulation of CXCR4, indicating that miR-338 might be a target for the treatment of IBD.