Metagenomic Next-Generation Sequencing-Based Fine-Needle Aspiration in Patients With Suspected Infected Pancreatic Necrosis.

Introduction: Fine-needle aspiration (FNA) is no longer recommended for diagnosing infected pancreatic necrosis (IPN) due to a high false-negative rate. Metagenomic next-generation sequencing (mNGS) is a valuable tool for identifying potential pathogens. We hypothesized that adding mNGS to the standard FNA procedure may increase diagnostic accuracy.

Methods: This is a prospective, single-arm feasibility study enrolling patients with acute necrotizing pancreatitis complicated by suspected IPN. Computed tomography-guided FNA was performed immediately after enrollment, and the drainage samples were subjected to culture and mNGS assays simultaneously. Confirmatory IPN within the following week of the index FNA procedure was the reference standard. The diagnostic performance of FNA-mNGS and the impact of mNGS results on treatment were evaluated. Historical controls were used for comparison of clinical outcomes.

Results: There was no significant difference between mNGS and culture in the positive rate (75% vs 70%, P = 0.723). The accuracy of FNA-mNGS was 80.0%, with a sensitivity of 82.35%, specificity of 66.67%, positive predictive value of 93.3%, and negative predictive value of 40.0%. The results of the mNGS led to treatment change in 16 of 20 patients (80%), including implementing percutaneous catheter drainage (n = 7), expanding antibiotic coverage (n = 2), percutaneous catheter drainage and expanding coverage (n = 4), narrowing antibiotic coverage (n = 1), and discontinuation of antibiotics (n = 2). The FNA-mNGS approach was not associated with improved clinical outcomes compared with the historical control group.

Discussion: The addition of mNGS to standard FNA has comparable diagnostic accuracy with culture-based FNA and may not be associated with improved clinical outcomes.