Diagnostic performance of the LRINEC score for diagnosing necrotizing fasciitis in a Latin American population.

Introduction: The Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) score was developed to estimate the likelihood of necrotizing fasciitis (NF); however, its diagnostic performance varies across populations, and evidence from Latin America remains limited. Objective: To assess the diagnostic performance of the LRINEC score in a Colombian population with skin and soft tissue infections. Materials and Methods: A retrospective cohort study was conducted among patients hospitalized at two tertiary care institutions in Colombia between 2016 and 2021. Patients with signs of systemic inflammatory response were considered suspected cases of NF. The diagnosis was confirmed or ruled out based on intraoperative or histopathologic findings. The LRINEC score was calculated, and its diagnostic performance was evaluated using sensitivity, specificity, and receiver operating characteristic (ROC) curves. Results: Among 1.546 medical records, 29 confirmed cases of NF and 106 suspected cases in which NF was ruled out were identified. The mean LRINEC score among patients with NF was 6 points. A cutoff score of ≥6 yielded a sensitivity of 62.07%, a specificity of 71.70%, and an area under the ROC curve (AUC) of 0.67. At a cutoff score of ≥8, sensitivity was 34.48%, and specificity was 89.62%. Discussion: These findings indicate moderate diagnostic performance, similar to that reported in other retrospective studies conducted in Latin American populations, with greater utility for ruling out NF than for ruling it in. Conclusion: The LRINEC score showed limited utility as a standalone diagnostic tool. A score <6 had a high negative predictive value and should always be interpreted in conjunction with clinical judgment.