Detection of potential pathogen in pancreatic fluid aspiration with metagenomic next-generation sequencing in patients with suspected infected pancreatic necrosis

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.

Management of infected acute necrotizing pancreatitis

Necrotizing or severe pancreatitis represents approximately 10%-20% of acute pancreatitis. 30%-40% of patients with acute necrotizing pancreatitis (ANP) will develop debris infection through translocation of intestinal microbial flora. Infected ANP constitutes a serious clinical condition and is complicated by severe sepsis with high mortality rates of up to 40% despite progress in current intensive care. The timely detection of sepsis is crucial. The Quick Sequential Organ Failure Assessment score, procalcitonin levels > 1.8 ng/mL and increased lactates > 2 mmol/L (> 18 mg/dL), indicate the need for urgent management. The escalated step-by-step management protocol starts with broad-spectrum antibiotics, percutaneous drainage or endoscopic management, and ends with surgical management if needed. The latter includes necrosectomy (either laparoscopic or traditional open surgery), peritoneal lavage and extensive drainage. This management protocol increases the chance of survival to approximately 60% in patients with otherwise fatal cases. Any treatment choice must be individualized, and the timing is critical.