Complex perianal fistulas are difficult to treat because of high recurrence rates and the need to preserve sphincter function. Negative pressure wound therapy (NPWT) improves healing in complex wounds, but its role in perianal fistula surgery is not well defined. This case series evaluated the feasibility, safety and early clinical outcomes of NPWT following surgical excision of complex perianal fistula tracts. A retrospective case series was conducted including eight adults with high or otherwise complex cryptoglandular perianal fistulas treated by surgical debridement followed by portable NPWT. Outcomes assessed were time to epithelialisation, symptom resolution, recurrence, complications and NPWT-related technical issues and refinements. Seven of eight patients achieved complete epithelialisation of the perianal wound after NPWT. One patient developed recurrence and required ongoing seton drainage. Over the course of the series, optimisation of sealing, sponge contouring and use of a bridge technique improved dressing reliability and wound progression. No NPWT device-related adverse events were observed. NPWT appears to be a feasible, well tolerated adjunct to surgery for complex cryptoglandular perianal fistulas, with high early healing rates and no device complications in this small series. Larger prospective studies are warranted to confirm efficacy and define optimal technical parameters.

This case describes a 31-year-old male who presented with acute exacerbation of pre-existing, undiagnosed Crohn's disease (CD) one week after rapid ascent to 4,500 meters. The patient had a long-standing history of recurrent oral ulcers and perianal fistulas. He was initially misdiagnosed with acute appendicitis based on right lower quadrant pain and fever, which resulted in emergency surgery. On postoperative day 9, life-threatening gastrointestinal bleeding (GIB) occurred. Management at the remote high-altitude facility was challenged by diagnostic limitations (lack of advanced imaging and endoscopic equipment), blood supply shortages, and lack of advanced interventions, which hindered the timely identification of the underlying disease and bleeding site. After emergency evacuation to lower altitude, GIB resolved spontaneously. Colonoscopy revealed ileocecal valve ulcers. Two-year follow-up with recurrent GIB and progressive intestinal ulceration further confirmed the diagnosis of CD. This case highlights ultra-high altitude exposure as a potential trigger for acute exacerbation of pre-existing CD, where atypical presentation often leads to misdiagnosis. The importance of recognizing extraintestinal manifestations in acute abdominal conditions is emphasized, alongside the critical challenges in managing complex cases in resource-limited high-altitude settings.

Fistula-associated adenocarcinoma (FAA) in Crohn's disease is an exceptionally rare and aggressive complication, often diagnosed late and historically managed with immediate radical surgery. Critically, the role of neoadjuvant chemoradiotherapy has remained undefined, with no reported cases of complete pathological response to date. We report the case of a 52-year-old man with longstanding Crohn's disease who developed a mucinous adenocarcinoma arising from a chronic perianal fistula, initially revealed by a perineal abscess. Histopathological analysis confirmed the diagnosis. Staging work-up demonstrated no evidence of distant metastasis. The patient underwent neoadjuvant chemoradiotherapy according to the PRODIGE-23 protocol, followed by abdominoperineal resection. Pathological assessment of the resection specimen demonstrated a complete pathological response (ypT0N0). This case highlights the importance of maintaining high clinical suspicion for malignant transformation in patients with chronic perianal fistulas in Crohn's disease and provides the first evidence that complete pathological response is achievable in fistula-associated adenocarcinoma, suggesting that neoadjuvant multimodal therapy may allow exploration of organ-preserving approaches in this rare condition.

This study systematically analyzed 170 registered clinical trials to clarify the global development landscape of stem cell therapy for inflammatory bowel disease (IBD) and its core challenges, and put forward corresponding future research directions. The results showed that the research on this therapy has accelerated significantly in the past three decades, with research geographically clustered in the US, China and Spain, and severe underrepresentation of African countries. The therapy is mainly focused on Crohn's disease (CD), especially refractory perianal fistulas, and mesenchymal stem cells (MSCs) account for over 70% of the applied cell types. Among 88 completed trials, 29.5% achieved primary endpoints, showing preliminary efficacy, yet the field faces prominent challenges: 20.6% of trials were prematurely terminated, early-phase studies dominate, Phase IV trials and long-term efficacy data are scarce, primary endpoints are highly heterogeneous, pediatric research is limited, and most completed trials have unknown outcomes. To address these issues, this study proposes that the future research should prioritize international cooperation to promote research equity, standardize efficacy endpoints, integrate long-term follow-up into study designs, optimize stem cell source and administration protocols, and implement precise patient selection. Overcoming these bottlenecks is essential to establish stem cell therapy as an effective complementary treatment for refractory IBD and improve the prognosis of patients unresponsive to conventional therapies.