Serum PCT, CRP and CD64 levels in predicting early infection after internal fixation of limb fractures / 中华临床感染病杂志

ABSTRACT

Objective:To investigate serum C-reactive protein (CRP) , procalcitonin (PCT) and neutrophil CD64 in predicting early infection after internal fixation of limb fractures.Methods:A total of 2 572 patients with limb fractures undergoing internal fixation in Taishun County People’s Hospital from January 2016 to December 2022 were enrolled. Postoperative infection occurred in 121 cases (infected group) and did not occur in 2 451 cases (uninfected group). Serum levels of PCT, CRP and CD64 were tested at admission and d1, d3, d5 and d7 after operation. Repeated measurement analysis of variance was used to compare the serum levels of PCT, CRP and CD64 at different time points between two groups, the receiver operating characteristic curve (ROC) was used to evaluate the predictive value of each index or in combination for early infection after internal fixation of limbs fractures.Results:The early infection rate after internal fixation was 4.70% (121/2 572). The levels of PCT, CRP and CD64 in the infection group began to rise after operation and decreased on d7; there were significant differences in PCT, CRP and CD64 levels between the two groups on d3, d5 and d7 after operation (PCT Ftime=678.607, Fintergroup=2 218.323, Finteraction=653.150; CRP Ftime=392.724, Fintergroup=1 812.502, FInteraction =379.577; CD64 Ftime=373.686, Fintergroup=4 817.438, Finteraction=528.353, all P< 0.001) . The area under the ROC curve of combined detection of PCT, CPR, and CD64 for predicting early infection was 0.856; the sensitivity and specificity of combined detection were 69.2% and 94.7%, respectively. The combined detection of three indicators showed better prediction values than PCT, CRP and CD64 alone ( Z=6.176, 3.838 and 2.431, P<0.01 or <0.05), and also better than combined detection of PCT and CRP ( Z=2.875, P=0.019). Conclusions:The combined detection of CD64, PCT and CRP is of value in prediction of postoperative infection after internal fixation of limb fractures, which is worthy of clinical application.