The Diagnostic Accuracy of Neutrophil-to-Lymphocyte Ratio (NLR) Compared to C-Reactive Protein (CRP) in Patients with Acute Cholecystitis: A Systematic Review and Meta-Analysis

Background/Objectives: Acute cholecystitis is associated with an increased risk of morbidity and mortality. Thus, early diagnosis and detection of complications are essential. Neutrophil-to-lymphocyte ratio (NLR) and C-reactive protein (CRP) are inflammatory biomarkers that could predict the diagnosis and complications of acute cholecystitis. Yet, the results of which biomarker has higher accuracy are inconsistent. Objective: To compare the accuracy of NLR and CRP in the diagnosis and prediction of complications in patients with acute cholecystitis. Methods: We searched PubMed, Scopus, and Web of Science in January 2026 for studies that compared both biomarkers (NLR and CRP) for the diagnosis and detection of complications or severity in patients with acute cholecystitis. We assessed the quality of the included studies using the QUADAS 2 tool. A bivariate meta-analysis was performed using R to compare the pooled diagnostic odds ratio (DOR) and the difference in sensitivity and specificity between both biomarkers. We used RevMan software to generate forest plots and summary receiver operating characteristic (SROC) curves using parameters calculated through R. Results: We included 15 studies in the systematic review, and 12 of them were included in the meta-analysis. The pooled data showed that NLR had higher accuracy in the diagnosis of acute cholecystitis compared to CRP, DOR 2.257 (95% CI 1.1, 4.633); however, there was no significant difference in sensitivity or specificity. There was no significant difference between NLR and CRP in detecting complications, including perforation, gangrene, and suppurative cholecystitis, DOR 1.100 (95% CI 0.817, 1.481). Meanwhile, NLR had similar sensitivity but lower specificity −0.050 (95% CI −0.090, −0.010) compared to CRP. NLR had lower overall accuracy in the detection of disease severity grades according to the Tokyo guidelines compared to CRP, DOR 0.170 (95% CI 0.081, 0.359), but higher specificity 0.230 (0.182, 0.279) compared to CRP. Conclusions: This systematic review and meta-analysis showed that NLR had higher diagnostic accuracy than CRP in patients with acute cholecystitis. However, both biomarkers had comparable sensitivity and specificity. Additionally, both biomarkers had comparable accuracy in detecting complications such as perforation, gangrene, or suppurative cholecystitis. CRP had higher overall accuracy in detecting disease severity according to the Tokyo guidelines. Thus, while NLR may be useful in diagnosing acute cholecystitis, CRP could be more effective in assessing disease severity. However, owing to the limited number of included studies, these findings should be interpreted with caution, and further studies are needed to confirm these results.