Advances in the management of acute pancreatitis

Effect of the Step-Jump Approach in Infected Pancreatic Necrosis: A Propensity Score-Matched Study

Purpose

The effects of the step-jump approach on the survival and prognosis of infected pancreatic necrosis (IPN) patients have not yet been determined.

Patients and Methods

Between November 2018 and June 2023, 188 patients were included in this study. There were 144 patients in the step-up group (the SU group) and 44 in the step-jump group (the SJ group). In the SU group, patients successfully treated with percutaneous catheter drainage (PCD) alone were classified into the SU-1 group (n=101), while those requiring additional surgery after PCD were categorized into the SU-2 group (n=43). In the SJ group, patients who underwent minimally invasive necrosectomy (MIN) without PCD were assigned to the SJ-1 group (n=34), whereas those who initially underwent PCD followed by immediate open surgery were placed in the SJ-2 group (n=10). Propensity score matching (PSM) was used to mitigate bias.

Results

After PSM, a total of 34 pairs were successfully matched. A comparison of the SU group with the SJ-1 group (upfront MIN without PCD) revealed similar mortality rates (P=0.239); however, the incidences of multiple drug-resistant organisms (MDROs) (P=0.029) and surgical complications (P<0.001) were significantly lower in the SJ-1 group. After comparing the SU-2 and SJ-2 groups (patients who underwent direct open necrosectomy without MIN after PCD failure), the incidences of surgical complications and MDRO in the SJ-2 group were significantly lower (P<0.05).

Conclusion

Compared with the step-up approach, the step-jump approach is safer and more effective and can significantly reduce the incidence of MDRO and surgical complications.

Biomimetic Trypsin-Responsive Structure-Bridged Mesoporous Organosilica Nanomedicine for Precise Treatment of Acute Pancreatitis

Developing strategies to target injured pancreatic acinar cells (PACs) in conjunction with primary pathophysiology-specific pharmacological therapy presents a challenge in the management of acute pancreatitis (AP). We designed and synthesized a trypsin-cleavable organosilica precursor bridged by arginine-based amide bonds, leveraging trypsin's ability to selectively identify guanidino groups on arginine via Asp189 at the active S1 pocket and cleave the carboxy-terminal (C-terminal) amide bond via catalytic triads. The precursors were incorporated into the framework of mesoporous silica nanoparticles (MSNs) for encapsulating the membrane-permeable Ca2+ chelator BAPTA-AM with a high loading content (∼43.9%). Mesenchymal stem cell membrane coating and surface modification with PAC-targeting ligands endow MSNs with inflammation recruitment and precise PAC-targeting abilities, resulting in the highest distribution at 3 h in the pancreas with 4.7-fold more accumulation than that of naked MSNs. The outcomes transpired as follows: After bioinspired MSNs' skeleton biodegradation by prematurely and massively activated trypsin, BAPTA-AM was on-demand released in injured PACs, thereby effectively eliminating intracellular calcium overload (reduced Ca2+ level by 81.3%), restoring cellular redox status, blocking inflammatory cascades, and inhibiting cell necrosis by impeding the IκBα/NF-κB/TNF-α/IL-6 and CaMK-II/p-RIP3/p-MLKL/caspase-8,9 signaling pathways. In AP mice, a single dose of the formulation significantly restored pancreatic function (lipase and amylase reduced more by 60%) and improved the survival rate from 50 to 91.6%. The formulation offers a potentially effective strategy for clinical translation in AP treatment.

Inflammation and Acinar Cell Dual-Targeting Nanomedicines for Synergistic Treatment of Acute Pancreatitis via Ca2+ Homeostasis Regulation and Pancreas Autodigestion Inhibition

Severe acute pancreatitis (AP) is a life-threatening pancreatic inflammatory disease with a high mortality rate (∼40%). Existing pharmaceutical therapies in development or in clinical trials showed insufficient treatment efficacy due to their single molecular therapeutic target, poor water solubility, short half-life, limited pancreas-targeting specificity, etc. Herein, acid-responsive hollow mesoporous Prussian blue nanoparticles wrapped with neutrophil membranes and surface modified with the N,N-dimethyl-1,3-propanediamine moiety were developed for codelivering membrane-permeable calcium chelator BAPTA-AM (BA) and trypsin activity inhibitor gabexate mesylate (Ga). In the AP mouse model, the formulation exhibited efficient recruitment at the inflammatory endothelium, trans-endothelial migration, and precise acinar cell targeting, resulting in rapid pancreatic localization and higher accumulation. A single low dose of the formulation (BA: 200 μg kg-1, Ga: 0.75 mg kg-1) significantly reduced pancreas function indicators to close to normal levels at 24 h, effectively restored the cell redox status, reduced apoptotic cell proportion, and blocked the systemic inflammatory amplified cascade, resulting in a dramatic increase in the survival rate from 58.3 to even 100%. Mechanistically, the formulation inhibited endoplasmic reticulum stress (IRE1/XBP1 and ATF4/CHOP axis) and restored impaired autophagy (Beclin-1/p62/LC3 axis), thereby preserving dying acinar cells and restoring the cellular "health status". This formulation provides an upstream therapeutic strategy with clinical translation prospects for AP management through synergistic ion homeostasis regulation and pancreatic autodigestion inhibition.

Predicting the risk of early intensive care unit admission for patients hospitalized with acute pancreatitis using supervised machine learning

Background

Acute pancreatitis (AP) is a complex and life-threatening disease. Early recognition of factors predicting morbidity and mortality is crucial. We aimed to develop and validate a pragmatic model to predict the individualized risk of early intensive care unit (ICU) admission for patients with AP.

Methods

The 2019 Nationwide Readmission Database was used to identify patients hospitalized with a primary diagnosis of AP without ICU admission. A matched comparison cohort of AP patients with ICU admission within 7 days of hospitalization was identified from the National Inpatient Sample after 1:N propensity score matching. The least absolute shrinkage and selection operator (LASSO) regression was used to select predictors and develop an ICU acute pancreatitis risk (IAPR) score validated by 10-fold cross-validation.

Results

A total of 1513 patients hospitalized for AP were included. The median age was 50.0 years (interquartile range: 39.0-63.0). The three predictors that were selected included hypoxia (area under the curve [AUC] 0.78), acute kidney injury (AUC 0.72), and cardiac arrhythmia (AUC 0.61). These variables were used to develop a nomogram that displayed excellent discrimination (AUC 0.874) (bootstrap bias-corrected 95% confidence interval 0.824-0.876). There was no evidence of miscalibration (test statistic = 2.88; P = 0.09). For high-risk patients (total score >6 points), the sensitivity was 68.94% and the specificity was 92.66%.

Conclusions

This supervised machine learning-based model can help recognize high-risk AP hospitalizations. Clinicians may use the IAPR score to identify patients with AP at high risk of ICU admission within the first week of hospitalization.

PRMT7-Dependent Transcriptional Activation of Hmgb2 Aggravates Severe Acute Pancreatitis by Promoting Acsl1-Induced Ferroptosis

Severe acute pancreatitis (SAP) is a highly fatal abdominal emergency, and its association with protein arginine methyltransferase 7 (PRMT7), the sole known type III enzyme responsible for the monomethylation of arginine residue, remains unexplored. In this study, we observe an increase in the PRMT7 levels in the pancreas of SAP mice and Cerulein-LPS-stimulated AR42J cells. Overexpression of Prmt7 exacerbated pancreatic damage in SAP, while the inhibition of PRMT7 improved SAP-induced pancreatic damage. Furthermore, PRMT7 overexpression promoted inflammation, oxidative stress, and ferroptosis during SAP. Mechanically, PRMT7 catalyzed monomethylation at histone H4 arginine 3 (H4R3me1) at the promoter region of high mobility group proteins 2 (HMGB2), thereby enhancing its transcriptional activity. Subsequently, HMGB2 facilitated Acyl CoA synthase long-chain family member 1 (ACSL1) transcription by binding to its promoter region, resulting in the activation of ferroptosis. Inhibition of PRMT7 effectively alleviated ferroptosis in Cerulein-LPS-induced AR42J cells by suppressing the HMGB2-ACSL1 pathway. Overall, our study reveals that PRMT7 plays a crucial role in promoting SAP through its regulation of the HMGB2-ACSL1 pathway to accelerate ferroptosis.

Recent Treatment Strategies for Acute Pancreatitis

Acute pancreatitis (AP) is a leading gastrointestinal disease that causes hospitalization. Initial management in the first 72 h after the diagnosis of AP is pivotal, which can influence the clinical outcomes of the disease. Initial management, including assessment of disease severity, fluid resuscitation, pain control, nutritional support, antibiotic use, and endoscopic retrograde cholangiopancreatography (ERCP) in gallstone pancreatitis, plays a fundamental role in AP treatment. Recent updates for fluid resuscitation, including treatment goals, the type, rate, volume, and duration, have triggered a paradigm shift from aggressive hydration with normal saline to goal-directed and non-aggressive hydration with lactated Ringer's solution. Evidence of the clinical benefit of early enteral feeding is becoming definitive. The routine use of prophylactic antibiotics is generally limited, and the procalcitonin-based algorithm of antibiotic use has recently been investigated to distinguish between inflammation and infection in patients with AP. Although urgent ERCP (within 24 h) should be performed for patients with gallstone pancreatitis and cholangitis, urgent ERCP is not indicated in patients without cholangitis. The management approach for patients with local complications of AP, particularly those with infected necrotizing pancreatitis, is discussed in detail, including indications, timing, anatomical considerations, and selection of intervention methods. Furthermore, convalescent treatment, including cholecystectomy in gallstone pancreatitis, lipid-lowering medications in hypertriglyceridemia-induced AP, and alcohol intervention in alcoholic pancreatitis, is also important for improving the prognosis and preventing recurrence in patients with AP. This review focuses on recent updates on the initial and convalescent management strategies for AP.