Abstract
<jats:p>Background. Early risk stratification in acute pancreatitis should address not only the detection of severe disease but also the timely prediction of persistent organ failure, infectious complications (including infected pancreatic necrosis), and mortality. The neutrophil-to-lymphocyte ratio (NLR) is an accessible first-line marker that can be obtained within the first hours of presentation. Objective: to assess the clinical utility of admission NLR for predicting persistent organ failure and mortality in acute pancreatitis. Materials and methods. We conducted a systematic review with meta-analytic synthesis of studies in which NLR was measured at hospital admission. Databases searched were PubMed, Scopus, and Google Scholar (through September 2025). Search terms included “neutrophil-to-lymphocyte ratio”, “NLR”, and “acute pancreatitis”; reference lists of included studies were hand-searched by two independent reviewers. Random-effects models (REML with Hartung-Knapp-Sidik-Jonkman adjustments) summarized associations; diagnostic performance was evaluated using bivariate/HSROC approaches. Results. Twenty-three studies were synthesized. Higher admission NLR was consistently associated with a greater frequency of persistent organ failure and in-hospital mortality. Summary models indicated moderate discriminative ability for both endpoints. Optimal cut-offs varied across studies; between-study heterogeneity was driven mainly by differences in thresholds and sample characteristics. Subgroup and sensitivity analyses preserved the direction of association; no clear evidence of substantial publication bias was detected. Conclusions. NLR is a simple, reproducible tool for early prediction of organ failure and mortality in acute pancreatitis. Use of time-specific, locally calibrated cut-offs and integration of NLR with clinical scores and basic laboratory parameters are recommended to improve early triage.</jats:p>