Application of metagenomic next-generation sequencing for suspected infected pancreatic necrosis

Diagnostic performance of pancreatic fluid aspiration through metagenomic next-generation sequencing for suspected infected pancreatic necrosis

AIMS

This study aimed to evaluate the diagnostic performance of metagenomic next-generation sequencing (mNGS) with pancreatic fluid aspiration for the detection of infected pancreatic necrosis (IPN).

METHODS

This retrospective observational study included 66 patients with suspected IPN. The participants simultaneously underwent pancreatic fluid aspiration mNGS, and microbial and blood culture. We compared the diagnostic performance of mNGS with that of culture in the detection of pathogens associated with IPN.

RESULTS

Of the 66 patients, 45 (68.2 %) were confirmed to have IPN. Pancreatic fluid aspiration mNGS yielded positive results in 32 of these patients (71.1 %), significantly outperforming microbial culture results (25 patients, 55.6 %; P = 0.039); however, both methods exhibited similar specificity (95.2% vs. 100 %). The results of pancreatic fluid aspiration mNGS and microbial culture matched in 73.3 % (33/45) of patients with IPN. The turnaround time for the mNGS results was significantly shorter than that for the microbial culture method (P < 0.001). In addition, survival analysis demonstrated that a positive mNGS result was not associated with increased mortality (hazard ratio, 0.652; 95 % confidence interval 0.157-2.699, P = 0.555).

CONCLUSIONS

Our study highlights the potential of mNGS for diagnosing IPN, with implications for improving patient care by facilitating early and accurate diagnosis, guiding appropriate interventions, and possibly improving patient outcomes.

Metagenomic next-generation sequencing, instead of procalcitonin, could guide antibiotic usage in patients with febrile acute necrotizing pancreatitis: a multicenter, prospective cohort study

BACKGROUNDS

The effectiveness of procalcitonin-based algorithms in guiding antibiotic usage for febrile acute necrotizing pancreatitis (ANP) remains controversial. Metagenomic next-generation sequencing (mNGS) has been applied to diagnose infectious diseases. The authors aimed to evaluate the effectiveness of blood mNGS in guiding antibiotic stewardship for febrile ANP.

MATERIALS AND METHODS

The prospective multicenter clinical trial was conducted at seven hospitals in China. Blood samples were collected during fever (T ≥38.5°C) from ANP patients. The effectiveness of blood mNGS, procalcitonin, and blood culture in diagnosing pancreatic infection was evaluated and compared. Additionally, the real-world utilization of antibiotics and the potential mNGS-guided antimicrobial strategy in febrile ANP were also analyzed.

RESULTS

From May 2023 to October 2023, a total of 78 patients with febrile ANP were enrolled and 30 patients (38.5%) were confirmed infected pancreatic necrosis (IPN). Compared with procalcitonin and blood culture, mNGS showed a significantly higher sensitivity rate (86.7% vs. 56.7% vs. 26.7%, P <0.001). Moreover, mNGS outperformed procalcitonin (89.5 vs. 61.4%, P <0.01) and blood culture (89.5 vs. 69.0%, P <0.01) in terms of negative predictive value. Blood mNGS exhibited the highest accuracy (85.7%) in diagnosing IPN and sterile pancreatic necrosis, significantly superior to both procalcitonin (65.7%) and blood culture (61.4%). In the multivariate analysis, positive blood mNGS (OR=60.2, P <0.001) and lower fibrinogen level (OR=2.0, P <0.05) were identified as independent predictors associated with IPN, whereas procalcitonin was not associated with IPN, but with increased mortality (Odds ratio=11.7, P =0.006). Overall, the rate of correct use of antibiotics in the cohort was only 18.6% (13/70) and would be improved to 81.4% (57/70) if adjusted according to the mNGS results.

CONCLUSION

Blood mNGS represents important progress in the early diagnosis of IPN, with particular importance in guiding antibiotic usage for patients with febrile ANP.

Time to think prime times for treatment of necrotizing pancreatitis: Pendulum conundrum

Pancreatic fluid collections (PFCs) typically develop as local complications of acute pancreatitis and complicate the clinical course of patients with acute pancreatitis and potentially fatal clinical outcomes. Interventions are required in cases of symptomatic walled-off necrosis (WON) (matured PFCs with necrosis) and pancreatic pseudocysts (matured PFCs without necrosis). In the management of necrotizing pancreatitis and WON, endoscopic ultrasound-guided transluminal drainage combined with on-demand endoscopic necrosectomy (i.e. the step-up approach) is increasingly used as a less invasive treatment modality compared with a surgical or percutaneous approach. Through the substantial research efforts and development of specific devices and stents (e.g. lumen-apposing metal stents), endoscopic techniques of PFC management have been standardized to some extent. However, there has been no consensus about timing of carrying out each treatment step; for instance, it is uncertain when direct endoscopic necrosectomy should be initiated and finished and when a plastic or metal stent should be removed following clinical treatment success. Despite emerging evidence for the effectiveness of noninterventional supportive treatment (e.g. antibiotics, nutritional support, irrigation of the cavity), there has been only limited data on the timing of starting and stopping the treatment. Large studies are required to optimize the timing of those treatment options and improve clinical outcomes of patients with PFCs. In this review, we summarize the current available evidence on the indications and timing of interventional and supportive treatment modalities for this patient population and discussed clinical unmet needs that should be addressed in future research.

Escherichia coli infection indicates favorable outcomes in patients with infected pancreatic necrosis

Introduction

Infected pancreatic necrosis (IPN) is a severe complication of acute necrotizing pancreatitis with increasing morbidity. Escherichia coli is the most frequently cultured microorganism in IPN. However, the implications of Escherichia coli infection on the outcomes of patients with IPN remain unclear. Therefore, this study aimed to evaluate the clinical impacts of Escherichia coli infection on IPN.

Methods

A prospective database with consecutive patients with IPN between January 2010 and April 2022 at a tertiary hospital was post-hoc analyzed. The clinical and microbiological characteristics, surgical management, and follow-up data of patients with and without Escherichia coli infection were compared.

Results

A total of 294 IPN patients were enrolled in this cohort. Compared with non-Escherichia coli infection cases (n=80, 27.2%), patients with Escherichia coli infection (n=214, 72.8%) were characterized by more frequent polymicrobial infections (77.5% vs. 65.0%, P=0.04) but a lower occurrence of severe acute pancreatitis (SAP) (42.5% vs. 61.7%, P=0.003). In addition, significantly lower mortality (12.5% vs. 30.4%, p=0.002), fewer step-up surgical interventions (73.8% vs. 85.1%, P=0.025), and a lower rate of multiple organ failure (MOF) (25.0% vs. 40.2%, P=0.016) were also observed in patients with Escherichia coli infection. Multivariate analysis of mortality predictors indicated that MOF (odds ratio [OR], 6.197; 95% confidence interval [CI], 2.373–16.187; P&lt;0.001) and hemorrhage (OR, 3.485; 95% CI, 1.623–7.487; P=0.001) were independent predictors associated with higher mortality in patients with IPN. Escherichia coli infection was significantly associated with a lower mortality (OR, 0.302; 95% CI, 0.121–0.751; P= 0.01).

Conclusion

Escherichia coli infection indicates a favorable prognosis in patients with IPN, although the mechanism needs further investigation.