The prognostic value of the neutrophil-lymphocyte ratio (NLR) in acute pancreatitis: identification of an optimal NLR.

INTRODUCTION: The neutrophil-lymphocyte ratio (NLR), calculated from the white cell differential count, provides a rapid indication of the extent of an inflammatory process. The aim of this study was to investigate the prognostic value of the NLR in acute pancreatitis (AP) and determine an optimal ratio for severity prediction.

MATERIALS AND METHODS: NLRs were calculated on days 0, 1, and 2, and correlated with severity. Severity was defined using the Atlanta classification.

RESULTS: One hundred forty-six consecutive patients managed were included, 22 with severe acute pancreatitis (SAP). NLR in SAP was significantly higher than in the favorable prognosis group on all 3 days (day 0, 15.5 vs. 10.5; day 1, 13.3 vs. 9.8; day 2, 10.8 vs. 7.6). The optimal cut-offs from ROC curves were 10.6 (day 0), 8.1 (day 1), and 4.8 (day 2) giving sensitivities of 63-90 %, specificities of 50-57 %, negative predictive value of 89.5-96.4 %, positive predictive values of 21.2-31.1 %, and accuracies of 57.7-60 %.

CONCLUSIONS: Elevation of the NLR during the first 48 h of admission is significantly associated with severe acute pancreatitis and is an independent negative prognostic indicator in AP.