Diagnostic accuracy of the leukocyte esterase test for native joint septic arthritis and prosthetic joint infections: a systematic review and meta-analysis.

backgroundsDiagnosing infectious arthritis, including native joint septic arthritis (NJSA) and prosthetic joint infections (PJI), is challenging but critical due to significant morbidity and mortality risks. The leukocyte esterase (LE) test shows promise as a quick, inexpensive diagnostic tool with high specificity. PURPOSES: This study aims to review and determine LE effectiveness for diagnosing both native and prosthetic joint infections and assess the extent to which methodological variations might affect its diagnostic accuracy. MATERIALS AND

methodsA systematic search of four databases was conducted to retrieve the studies on the diagnostic accuracy of the leukocyte esterase strip test for the detection of NJSA or PJI from inception to August 2025. The studies were screened independently by two authors, and the required data were extracted from the full text of the included studies. The extracted data was analyzed using bivariate random effects meta-analysis and subgroup analysis was done to assess the impact of possible affecting factors.

resultsAfter deduplication, 179 studies were further evaluated for inclusion in our study. Following the revision of full texts, 45 studies were included (with a total of 6682 patients, comprising 1971 infection cases and 4711 non-infection cases). For NJSA, eight studies yielded a pooled sensitivity of 86.5% (95% CI: 80.6%-90.8%), specificity of 67.9% (95% CI: 44.4%-84.9%), and diagnostic odds ratio (DOR) of 24.6 (95% CI: 6.6–91.6, I²: 62%). The pooled AUC was 0.86 (95% CI: 0.78–0.89). Subgroup analyses showed no significant impact of waiting time, test repetition, or centrifugation on diagnostic accuracy. For PJI, 38 studies revealed a pooled sensitivity of 77.9% (95% CI: 71.0%-83.5%), specificity of 92.9% (95% CI: 90.9%-94.5%), and DOR of 60.0 (95% CI: 35.9-100.3, I²: 70.9%), with an AUC of 0.941 (95% CI: 0.902–0.940). After removing outlier studies, the recalculated DOR was 61.8 (95% CI: 44.9–84.9, I²: 42.6%). Subgroup analyses for waiting time, test repetition, centrifugation, LE thresholds, and reference tests revealed no significant differences in diagnostic accuracy across groups.

conclusionIn both NJSA and PJI, variations in methodological factors did not significantly affect the LE strip test’s diagnostic accuracy; the LE test may serve as a useful adjunctive screening tool for joint infections, although its performance, particularly in NJSA, should be interpreted in the context of substantial between-study heterogeneity. For PJI, the LE test demonstrates higher overall accuracy and specificity sufficient to rule in infection. However, for NJSA, the LE test shows only moderate specificity and variability across studies, suggesting that positive results should be further investigated and interpreted cautiously. The observed heterogeneity, especially in NJSA analyses, limits the generalizability of pooled estimates and underscores the need for cautious clinical interpretation.