Application of the laboratory risk indicator for necrotizing fasciitis score to the head and neck: a systematic review and meta-analysis

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.

Hematologic and inflammatory parameters for determining severity of odontogenic infections at admission: a retrospective study

BACKGROUND

Severe odontogenic infections in the head and neck region, especially necrotizing soft tissue infection (NSTI) and deep neck abscess, are potentially fatal due to their delayed diagnosis and treatment. Clinically, it is often difficult to distinguish NSTI and deep neck abscess in its early stage from cellulitis, and the decision to perform contrast-enhanced computed tomography imaging for detection is often a challenge. This retrospective case-control study aimed to examine the utility of routine blood tests as an adjunctive diagnostic tool for NSTI in the head and neck region and deep neck abscesses.

METHODS

Patients with severe odontogenic infections in the head and neck region that required hospitalization were classified into four groups. At admission, hematologic and inflammatory parameters were calculated according to the blood test results. In addition, a decision tree analysis was performed to detect NSTI and deep neck abscesses.

RESULTS

There were 271 patients, 45.4% in Group I (cellulitis), 22.5% in Group II (cellulitis with shallow abscess formation), 27.3% in Group III (deep neck abscess), and 4.8% in Group IV (NSTI). All hematologic and inflammatory parameters were higher in Groups III and IV. The Laboratory Risk Indicator for Necrotizing Fasciitis score, with a cut-off value of 6 and C-reactive protein (CRP) + the neutrophil-to-lymphocyte ratio (NLR), with a cut-off of 27, were remarkably useful for the exclusion diagnosis for Group IV. The decision tree analysis showed that the systemic immune-inflammation index (SII) of ≥ 282 or < 282 but with a CRP + NLR of ≥ 25 suggests Group III + IV and the classification accuracy was 89.3%.

CONCLUSIONS

Hematologic and inflammatory parameters calculated using routine blood tests can be helpful as an adjunctive diagnostic tool in the early diagnosis of potentially fatal odontogenic infections. An SII of ≥ 282 or < 282 but with a CRP + NLR of ≥ 25 can be useful in the decision-making for performing contrast-enhanced computed tomography imaging.