Regenerative Therapy for Crohn’s Disease: One-Year Results of MSC Injections for Perianal Fistulas

Aims Perianal lesions affect 25–30% of Crohn’s disease patients during the course of their illness. These lesions are often refractory to conventional and biologic therapies due to persistent pelvic inflammation and recurrent local infections, which exacerbate tissue damage. Recent studies have demonstrated the efficacy of adipose-derived mesenchymal stem cell (MSC) injections for treating perianal fistulas, reporting closure rates exceeding 50% at one year, with excellent safety profiles. However, this treatment is not yet widely available. This study evaluates the feasibility, safety, and efficacy of hematopoietic MSC injections produced at the Regenerative Medicine Center annexed to Mohammed VI University Hospital in Marrakech, for treating perianal fistulas in Crohn’s disease. Secondary objectives include assessing treatment impact on quality of life and perianal disease activity at weeks 12 and 48.

Methods This prospective observational study was conducted at Mohammed VI University Hospital, from October 2021 to October 2023. Adults with perianal Crohn’s disease and setons placed for at least six weeks were eligible. Exclusion criteria included undrained perianal abscesses. Hematopoietic MSCs were isolated locally from donor peripheral blood. A dose of 3×10⁶ MSCs was injected by a colorectal surgeon, with half administered through the internal fistula opening and the other half through the external opening. The internal opening was sutured. Baseline and follow-up assessments (weeks 0, 4, 12, 24, 36, and 48) included clinical examination, CDAI, PRO scores, CRP, calprotectin, quality of life (Short Health Scale, SHS), and pelvic MRI. Perianal disease activity (PDAI) was evaluated at inclusion and week 48. Efficacy was defined as complete closure of external openings with no drainage under pressure and no abscess on MRI.

Results Sixteen patients were included. Median age was 49 years, with a median anal disease duration of 8 years. Six patients had two external openings, while 10 had one. Setons had been in place for a median of 16 months. At baseline, 69% of patients were on anti-TNF therapy. Median baseline CDAI and PDAI scores were 97.5 and 5, respectively. At weeks 12 and 48, complete fistula closure was achieved in 63% (10/16) and 50% (8/16) of patients, respectively. Among patients with two fistulas, one or both were closed in the majority by week 12. One patient developed an anal abscess requiring drainage and seton placement, with no further abscess recurrence during follow-up. Perianal disease activity (PDAI) and quality of life (SHS) scores progressively improved.

Conclusions Locally produced hematopoietic MSC therapy for perianal Crohn’s disease is feasible, safe, and effective, achieving closure rates comparable to international studies (50% at one year). This therapy also improves quality of life and perianal disease activity, positioning it as a promising option in regenerative medicine.

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Artikel online veröffentlicht:
27. März 2025