Abstract:

Objective To analyze the predictive value of serum levels of procalcitonin （PCT） and cytokines on the prognosis of patients with COVID?19 at admission. Methods From November 2022 to February 2023， patients diagnosed with COVID?19 who were admitted to Beijing Chest Hospital were enrolled. Chemiluminescence was used to detect serum PCT levels， and flow microsphere array was used to detect serum cytokines IL?1β， IL ?2， IL?4， IL?5， IL?6， IL?8， IL?10， IL?12p70， IL?17A， IL?17F， IL?22， TNF?α， TNF?β， IFN?γ level. ICU admission， mechanical ventilation and in?hospital death were defined as poor prognosis. After excluding patients with bacterial infection， the relationship between serum PCT and cytokine levels at admission and the prognosis of COVID?19 patients was analyzed. After excluding patients with bacterial infection， the relationship between serum PCT and cytokine levels at admission and the prognosis of COVID?19 patients was analyzed. Results A total of 176 patients with complete data were included， including 134 in the PCT?normal group and 42 in the PCT?elevated group， with a median age of 71.50 years and 71.59% males. Patients in the PCT elevated?group had significantly higher rates of ICU admission （38.41% vs. 13.11%， P < 0.05）， mechanical ventilation （76.92% vs. 24.59%， P < 0.001） and in?hospital mortality （38.46% vs. 6.56%， P < 0.001） were significantly higher than those in the PCT?normal group. Serum levels of cytokines IL?6 （7.40 pg/mL vs. 4.78 pg/mL， P = 0.033 4） and IL?8 （10.97 pg/mL vs. 5.92 pg/mL， P < 0.001） were significantly higher in patients with poor prognosis than in those with good prognosis. The area under the curve for PCT， IL?6， and IL?8 to predict poor prognosis in COVID?19 patients was 0.687， 0.660， and 0.746， respectively； sensitivity was 52.78%， 55.17%， and 72.41%， respectively； and specificity was 81.58%， 74.19%， and 74.19%， respectively， as calculated from the ROC curve. When PCT， IL?6 and IL?8 jointly predict the prognosis of COVID?19 patients， the area under the curve is 0.764， the sensitivity is 70.00%， and the specificity is 80.00%. Conclusion Serum PCT and cytokines IL?6 and IL?8 could be used as predictive markers for poor prognosis in patients with COVID?19.

Key words: COVID?19 infection, cytokines, procalcitonin, prognosis