Predictive value of serum procalcitonin and hypersensitive C-reactive protein levels in patients with acute cerebral infarction complicated with infection

Abstract

To analyze the changes of early procalcitonin (PCT) and hypersensitive C-reactive protein (hs-CRP) in patients with acute cerebral infarction, and to explore the predictive value of both for acute cerebral infarction with infection. 206 acute cerebral infarction patients admitted to the department of neurology of Feicheng Mining Center Hospital from May 2014 to May 2019 were enrolled. Clinical data of patients and serum PCT and hs-CRP levels at 24, 48 and 72 hours after onset were collected. Patients were divided into infected group (n = 69) and non-infected group (n = 137) according to whether infection occurred within 5 days after onset. And 60 healthy people in the same period were selected as the healthy control group. The trends of serum PCT and hs-CRP levels in each group were analyzed. The receiver operating characteristic (ROC) curve was used to analyze the values of serum PCT and hs-CRP levels in identifying acute cerebral infarction with infection. The serum level of PCT at 24, 48 and 72 hours in the infected group and the non-infected group were significantly higher than those in the healthy control group, and the serum level of PCT at 48 hours and 72 hours in the infected group were significantly higher than those in the non-infected group (μg/L: 0.28±0.08 vs. 0.19±0.03, 0.31±0.07 vs. 0.15±0.06, both P < 0.05). Compared with 24 hours, the serum PCT level in the infected group at 48 hours and 72 hours were significantly increased, but decreased in the non-infected group. The serum hs-CRP level in the infected group at 24, 48 and 72 hours were significantly higher than those in the non-infected group and the healthy control group (mg/L: 5.86±1.73 vs. 5.45±1.08, 5.25±1.33; 8.01±2.41 vs. 5.67±2.13, 5.25±1.33; 14.25±2.19 vs. 12.30±1.87, 5.25±1.33; all P < 0.05). And the serum hs-CRP level in the non-infected group at 72 hours was significantly higher than that in the healthy control group. Compared with 24 hours, the serum hs-CRP level in the infected group and non-infected group at 48 hours and 72 hours were significantly increased. It was shown by ROC curve analysis that serum PCT and hs-CRP levels at 24 hours had no predictive value for infection in patients with acute cerebral infarction [area under ROC curve (AUC) was 0.440, 0.576 respectively, both P > 0.05]. At 48 hours, the AUC of serum PCT in diagnosis of acute cerebral infarction with infection was 0.850 [95% confidence interval (95%CI) = 0.784-0.916], the sensitivity and specificity were 66.7% and 97.8% when the cut-off of PCT was 0.25 μg/L; the AUC of serum hs-CRP was 0.759 (95%CI = 0.689-0.830), the sensitivity and specificity were 66.7% and 76.6% when the cut-off of hs-CRP was 6.80 mg/L; the AUC of PCT combined with hs-CRP was 0.911 (95%CI = 0.859-0.964), the sensitivity was 90.5%, the specificity was 86.9%. At 72 hours, the AUC of serum PCT in diagnosis of acute cerebral infarction with infection was 0.952 (95%CI = 0.916-0.989), the sensitivity and specificity were 89.9% and 93.4% when the cut-off of PCT was 0.23 μg/L; the AUC of serum hs-CRP was 0.753 (95%CI = 0.678-0.828), the sensitivity and specificity were 60.9% and 83.2% when the cut-off of hs-CRP was 14.01 mg/L; the AUC of PCT combined with hs-CRP was 0.954 (95%CI = 0.918-0.991), the sensitivity was 97.1%, and the specificity was 89.8%. The results showed that the diagnostic value of serum PCT at 48 hours and 72 hours were higher than those of hs-CRP, and the predictive value of PCT combined with hs-CRP was higher than those of single index. Acute cerebral infarction itself has an effect on serum PCT level; serum PCT level above 0.23 μg/L at 72 hours after onset and reference to serum hs-CRP level have a high predictive value for the diagnosis of infection in patients with acute cerebral infarction.