Does obesity affect the diagnostic value of various biomarkers for periprosthetic joint infections? A single center...

The aim of this study was to examine the impact of obesity on the diagnosis of periprosthetic joint infections (PJI) by assessing the levels and diagnostic efficacy of biomarkers.

A total of 254 patients were divided into obese group (n=59) and non-obese group (n=195) according to BMI. Each group was further divided into the PJI group and the AF group. Data on CRP, ESR, fibrinogen, D-dimer, CRP-albumin ratio (CAR), CRP-lymphocyte ratio (CLR), and CRP-monocyte ratio (CMR) were collected from all patients. ROC curve was performed to evaluate the diagnostic values of these biomarkers.

The levels of biomarkers were significantly higher in PJI patients compared to the AF patients in both the obese and non-obese groups (P < 0.001), but the levels of biomarkers were similar between the obese and non-obese groups. In the obese group, CRP exhibited the highest diagnostic value (AUC=0.982). In the non-obese group, CAR demonstrated the highest diagnostic value (AUC =0.935). Subgroup analysis showed no significant differences in biomarker levels (P > 0.05).

Obesity did not affect biomarker levels in patients with PJI. But for obese patients, the diagnostic thresholds for CRP and ESR are higher, and clinical diagnosis should be careful to avoid false positives. CRP and CAR were identified as the most effective biomarkers for diagnosing PJI in the obese and non-obese groups, respectively.