Diagnostic value of inflammatory indices and triglycerides in hyperlipidemic acute pancreatitis.

OBJECTIVE: High triglyceride (TG) levels complicate the diagnosis of acute pancreatitis (AP) due to delayed lipid testing. This study evaluates the diagnostic value of inflammatory indices, particularly the platelet-to-lymphocyte ratio (PLR) and systemic inflammation response index (SIRI), for identifying hyperlipidemic acute pancreatitis (HLAP). METHODS: A retrospective cohort study analyzed 140 AP patients (59 HLAP, 81 non-HLAP) admitted between January 2023 and December 2024. The HLAP group was further stratified into gray-zone (HLAP-G) and typical (HLAP-S) subgroups. Healthy controls (HC, n=80) and individuals with simple hypertriglyceridemia (HTG, n=80) were included for comparison. Inflammatory indices (PLR, SIRI, NLR, MLR, SII) were calculated from admission blood counts. Diagnostic performance was assessed using ROC analysis, and a combined model (PLR+SIRI+TG) was developed and validated in an external cohort. Dynamic changes of PLR and SIRI were evaluated at 1, 6, and 12 hours post-admission. RESULTS: PLR, SIRI, and other indices were significantly higher in the HLAP group than in the non-HLAP, HTG, and HC groups (all P < 0.01), showing a stepwise increase from HC to HLAP-S. SIRI demonstrated the highest diagnostic efficacy for HLAP (AUC=0.973, sensitivity =91.5%, specificity =96.3%), followed by PLR (AUC=0.960). The combined model achieved the highest AUC (0.988), with external validation confirming generalizability (AUC=0.845). Dynamic profiles revealed peak PLR and SIRI at 6 hours post-admission. Multivariate analysis identified PLR and SIRI as independent risk factors for HLAP. CONCLUSIONS: PLR and SIRI are valuable, easily accessible tools for early HLAP diagnosis. Their high diagnostic accuracy, particularly when combined with TG, provides a robust method for prompt identification and targeted therapy.