血清降钙素原联合血乳酸水平对老年COPD合并下呼吸道细菌感染的预后判断价值

Prognostic value of serum procalcitonin combined with blood lactate level in elderly patients with COPD complicated with lower respiratory tract bacterial infection

目的 探讨血清降钙素原(PCT)、血乳酸(LAC)水平对老年慢性阻塞性肺疾病(COPD)合并下呼吸道细菌感染的预后判断价值。方法 选取2019年5月~2022年5月在本院入院治疗的老年COPD合并下呼吸道细菌感染患者95例为观察组。根据治疗后60d的随访情况,将患者分为预后不良组53例和预后良好组42例,另取同期入院治疗的未发生下呼吸道细菌感染的老年COPD患者107例为对照组。ELISA法检测血清PCT水平;血气分析仪检测血LAC水平;Pearson法分析老年COPD合并下呼吸道细菌感染患者血清PCT与血LAC水平的相关性;Logistic回归分析老年COPD合并下呼吸道细菌感染患者预后不良的影响因素;ROC曲线分析血清PCT水平与血LAC水平对老年COPD合并下呼吸道细菌感染预后不良的诊断价值。结果 观察组PCT、LAC水平分别为(1.97±0.51)ng/mL、(1.97±0.51)mmol/L,高于对照组PCT、LAC水平(1.02±0.29)ng/mL、(4.31±1.31)mmol/L,血氧分压(PaO2)(87.33±10.31)mmHg,显著低于对照组(92.21±11.14)mmHg,差异均具有统计学意义(t=16.500、6.930、3.218,P<0.05);预后不良组PCT水平为(2.33±0.56)ng/mL、LAC为(6.54±1.70)mmol/L显著高于预后良好组PCT水平(1.52±0.34)ng/mL、LAC(4.71±1.25)mmol/L,且PaO2水平(83.31±14.62)mmHg显著低于预后良好组(90.52±18.25)mmHg,差异均具有统计学意义(t=8.242、5.835、5.835,P<0.05);老年COPD合并下呼吸道细菌感染患者血清PCT与血LAC水平呈正相关(r=0.554,P<0.01);PCT、LAC是影响老年COPD合并下呼吸道细菌感染患者预后不良的危险因素(P<0.05);血清PCT水平、血LAC水平诊断老年COPD合并下呼吸道细菌感染预后不良的最佳截断值分别为2.06 ng/mL、6.18 mmol/L,两者联合诊断的AUC为0.957,敏感度为86.79%,特异性为92.86%。结论 老年COPD合并下呼吸道细菌感染患者血清PCT水平、血LAC水平升高,二者联合对老年COPD合并下呼吸道细菌感染预后不良的判断具有重要参考价值。

Objective To explore the prognostic value of serum procalcitonin(PCT)and blood lactate(LAC)in elderly patients with chronic obstructive pulmonary disease(COPD)complicated with lower respiratory tract bacterial infection.1Methods A total of 95 elderly COPD patients with lower respiratory tract bacterial infections admitted to our hospital from May 2019 to May 2022 were collected as the observation group.Based on the 60 day follow-up after treatment,the patients were grouped into a poor prognosis group of 53 cases and a good prognosis group of 42 cases,another 107 elderly COPD patients who did not experience lower respiratory tract bacterial infection during the same period of hospitalization were collected as the control group.ELISA method was applied to detect serum PCT level;blood gas analyzer was applied to detect blood LAC level;Pearson method was applied to analyze the correlation between serum PCT and blood LAC levels in elderly COPD patients with lower respiratory tract bacterial infection;Logistic regression was applied to analyze the influencing factors of poor prognosis in elderly COPD patients with lower respiratory tract bacterial infection;ROC curve was applied to analyze the diagnostic value of serum PCT level and serum LAC level for poor prognosis in elderly COPD patients with lower respiratory tract bacterial infection.Results The levels of PCT and LAC in the observation group were(1.97±0.51)ng/mL and(1.97±0.51)mmol/L,respectively,which were higher than those in the control group(1.02±0.29)ng/mL and(4.31±1.31)mmol/L.The blood oxygen partial pressure(PaO,)of the observation group(87.33±10.31)mmHg was significantly lower than that of the control group(92.21±11.14)mmHg,and the differences were statistically significant(t=16.500,6.930,3.218,P<0.05);The levels of PCT(2.33±0.56)ng/mL and LAC(6.54±1.70)mmol/L in the poor prognosis group were significantly higher than those in the good prognosis group(1.52±0.34)ng/mL and LAC(4.71±1.25)mmol/L,and the PaO,(83.31±14.62)mmHg in the poor prognosis group was significantly lower than that in the good prognosis group(90.52±18.25)mmHg,with statistical significance(t=8.242,5.835,5.835,P<0.05);there was a positive correlation between serum PCT and serum LAC levels in elderly COPD patients with lower respiratory tract bacterial infection(r=0.554,P<0.01);PCT and LAC were risk factors for poor prognosis in elderly COPD patients with lower respiratory tract bacterial infection(P<0.O5);the optimal cutoff value for diagnosing poor prognosis in elderly COPD patients with lower respiratory tract bacterial infection by serum PCT level and blood LAC level was 2.06 ng/mL and 6.18 mmol/L,respectively,the combined diagnosis of AUC was 0.957,with a sensitivity of 86.79% and a specificity of 92.86%.Conclusion Serum PCT level and blood LAC level increase in elderly COPD patients with lower respiratory tract bacterial infection.The combination of the two has high value in predicting poor prognosis of elderly COPD patients with lower respiratory tract bacterial infection.