Systematic review and meta-analysis of the diagnostic accuracy of inflammatory markers for infected diabetic foot ulcer

Background: The aim was to evaluate the diagnostic value of ESR, CPR, PCT, and WBC in patients with infected diabetic foot ulcer (DFU). Methods: The MEDLINE, Embase, BIOSIS, Cochrane databases, and Web of Knowledge databases were searched, without language restriction, to July 2023. Original studies were selected that reported the performance of ESR, CPR, PCT, and WBC in diagnosing infected DFU. To assess the diagnostic value of biomarkers for infected DFU, pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and area under the summary receiver operating characteristic curve (ROC-AUC) were calculated. Results: Ten studies with 765 patients were identified in our meta-analysis. The pooled sensitivity and specificity of ESR was 0.82 (95 % CI: 0.68-0.91) and 0.83 (95 % CI: 0.69-0.91) respectively. The pooled sensitivity and specificity of CRP was 0.81 (95 % CI: 0.65-0.91) and 0.91 (95 % CI: 0.79-0.96) respectively. The pooled sensitivity and specificity of PCT was 0.76 (95 % CI: 0.65-0.85) and 0.89 (95 % CI: 0.78-0.95) respectively. The pooled sensitivity and specificity of WBC was 0.75 (95 % CI: 0.64-0.83) and 0.79 (95 % CI: 0.67-0.88) respectively. CRP showed the best diagnostic accuracy at distinguishing infected DFU from noninfected DFU with an AUC of 0.93, followed by PCT (AUC of 0.89), ESR (AUC of 0.89), and WBC (AUC of 0.84). Conclusion: CPR levels had high efficiency in distinguishing infected DFU from noninfected DFU, followed by PCT, ESR and WBC. All of these biomarkers could be helpful for early diagnosis of infected DFU. New biomarkers for improving medical decision in diagnosis of infected DFU are highly desirable.