Objective:

To evaluate the diagnostic accuracy of the cerebrospinal fluid glucose-to-lactate ratio (CGLR) for detecting postoperative intracranial infections in patients with acute brain injury (ABI) and compare it explicitly with conventional biomarkers such as cLac and cGlu.

Key Findings:

• CGLR demonstrated a higher diagnostic performance (AUC = 0.866) compared to cGlu (AUC = 0.836) and cLac (AUC = 0.820), with statistical significance noted.
• Optimal cutoffs were determined: 2.6 mmol⋅L–1 for cGlu, 4.5 mmol⋅L–1 for cLac, and 0.61 for CGLR.
• CGLR values were similar between hyperglycemic and normoglycemic patients, regardless of infection status, with all P > 0.05.

Interpretation:

CGLR is a rapid, cost-effective, and reliable biomarker for diagnosing postoperative intracranial infections in ABI patients, outperforming traditional markers and remaining unaffected by peripheral glucose fluctuations, which is crucial for clinical application.

Limitations:

• Single-center study may limit generalizability.
• Exclusion criteria may affect the applicability of findings to broader populations, particularly in diverse clinical settings.

Conclusion:

CGLR is a promising biomarker for diagnosing postoperative intracranial infections in ABI patients, warranting further studies to validate these findings.