Introduction

Patients with necrotizing pancreatitis are at risk of developing numerous complications as a consequence of their more severe disease course. Effective drainage strategies are essential for patients with symptomatic walled off necroses (WON). Here, most patients receive interventional-endoscopic drainage using Lumen apposing metal stents (LAMS)¹. However, LAMS-associated complications such as occlusion are still considered a relevant clinical problem. Occlusion rates ranging from 3,8% to 24,3% of all LAMS applied have been reported in literature^1,2. Thus far, few studies have identified factors, which could potentially affect LAMS occlusion rate such as preemptive placement of coaxial double pigtails through the LAMS³. A recent study suggested a potential influence of Proton Pump Inhibitors (PPI) on LAMS occlusion and the rate of endoscopic necrosectomies⁴. However, the results of this study were contradictory.

Aims & Methods

We performed a European-wide distributed expert survey in combination with a European-wide multicentric retrospective cohort study. Data was acquired using the electronic case record form (eCRF) tool REDCap and analyzed using R Studio (V4.2.3). 75 interventional endoscopists participated in the expert survey and 882 patients with 956 LAMS implanted were included in the retrospective cohort study. The primary aim of the expert survey was to assess the clinical relevance of LAMS occlusion. The primary aim of the retrospective cohort study was to investigate the potential correlation of PPI intake and LAMS occlusion and the numbers of necrosectomies.

Results

We observed that in the majority of cases, patients included received PPIs (746 cases (79.3%) with versus 195 without PPIs (20.7%). Moreover, we observed that a relevant number of experts would discontinue PPIs upon LAMS implantation (n=18; 27%) – even though this is not resembled by the real-world data. By performing a multivariable logistic regression of various factors potentially affecting LAMS occlusion we show that concomitant continuous intake of PPIs significantly increases the LAMS occlusion rate (Odds Ratio (OR): 0.62; p-value 0.045). Moreover, our data reveals that patients who continuously receive PPIs exhibit a significantly higher rate of required endoscopic necrosectomies (mean continuous PPI intake: 4.13; mean no PPI intake: 2.99; p-value 0.006). In addition, we show that this effect is dose-dependent with a significantly higher necrosectomy rate in patients who receive more than double the standard PPI dose in comparison to the standard dose of PPIs (p-value <0.001). For other complications such as relevant gastrointestinal bleeding (defined as with a need for blood transfusions or interventional measures) we did not observe any significant differences between the PPI and the Non-PPI group (bleeding: OR 1.37, p-value 0.3).

Conclusion

Our data suggests that concomitant PPI-intake could be disadvantageous in patients receiving LAMS. However, further studies are needed to investigate the mechanism behind the effects observed and to validate our findings prospectively.

References

1. Chandrasekhara, V. et al. Safety and efficacy of lumen-apposing metal stents versus plastic stents to treat walled-off pancreatic necrosis: systematic review and meta-analysis. Endosc Int Open 08, E1639–E1653 (2020).
2. Giri, S., Harindranath, S., Afzalpurkar, S., Angadi, S. & Sundaram, S. Does a coaxial double pigtail stent reduce adverse events after lumen apposing metal stent placement for pancreatic fluid collections? A systematic review and meta-analysis. Ther Adv Gastrointest Endosc 16, (2023).
3. Gopakumar, H. Endoscopic ultrasound-guided lumen-apposing metal stent with or without coaxial plastic stent for pancreatic fluid collections: a systematic review and meta-analysis comparing safety and efficacy. Ann Gastroenterol (2024) doi:10.20524/aog.2024.0858.
4. Powers, P. C. et al. Discontinuation of proton pump inhibitor use reduces the number of endoscopic procedures required for resolution of walled-off pancreatic necrosis. Endosc Ultrasound 8, 194–198 (2019).