C-reactive protein and neutrophil-to-lymphocyte ratio as key inflammatory indicators in the diagnosis of cervical necrotizing fasciitis.

Background: Cervical necrotizing fasciitis (CNF) is a life-threatening bacterial infection with a diagnostic challenge. Currently, there is insufficient evidence on the diagnostic accuracy of inflammatory indicators in CNF.

Objective: This study aims to identify key inflammatory indicators and assess their diagnostic accuracy for CNF.

Methods: A diagnostic case-control study was conducted at a tertiary healthcare facility from January 2020 to December 2023. Laboratory data from patients with CNF and non-CNF at admission were evaluated. Key inflammatory indicators were identified through consistent outcomes from multivariable logistic regression and receiver operating characteristic curves analyses. The diagnostic accuracy of these indicators, with the results of combined tests, were calculated.

Results: CNF was confirmed in 21 of the 67 patients investigated. C-reactive protein (CRP) and neutrophil-to-lymphocyte ratio (NLR) were identified as key inflammatory indicators, with sensitivities of 0.905 and 0.810, and specificities of 0.870 and 0.913, respectively, at CRP threshold of 165.0 mg/L and NLR of 15.8. Combining CRP and NLR in parallel and serial tests increased sensitivity to 0.952 and specificity to 1.0, respectively.

Conclusions and significance: CRP and NLR have been verified as key inflammatory indicators with satisfactory diagnostic abilities for CNF diagnosis, providing a strong foundation for future studies.