脓毒症患儿降钙素原测定的临床意义

Clinical Significance of Procalcitonin Measurement in Children with Sepsis

目的探讨血清降钙素原（PCT）检测在小儿脓毒症中的应用价值。方法2005年3月～12月PICU感染患儿62例。男33例，女29例；年龄1个月～11岁。分为脓毒症组（30例）和非脓毒症组（32例）。脓毒症组进一步分为严重脓毒症和非严重脓毒症组。所有患儿于住院24h内进行降钙素原（PCT）、C-反应蛋白（CRP）、白细胞（WBC）计数、血气分析和病原学检测，并进行小儿危重病例评分。结果脓毒症组PCT、CRP、WBC水平明显高于非脓毒症组（P〈0．01）；严重脓毒症组PCT水平明显高于非严重脓毒症组，但二组CRP和WBC水平无显著差异。危重病例评分二组间差异有显著性。当PCT≥2．2μg／L时诊断脓毒症的敏感性、特异性、阳性预测值、阴性预测值分别为96．7％、87．5％、87．9％和96．5％，ROC曲线下面积为0．992；当CRP≥25mg／L时分别为83％、75％、75．8％、82．8％和0．796；当WBC≥13．09×10^9／L时分别为53％、75％、69．6％、64．1％和0．651。62例患儿PCT水平与危重评分呈显著负相关（r=-0．64 P〈0．01）。结论在鉴别脓毒症与非脓毒症时，PCT优于WBC和CRP，是敏感的血清学标志物。PCT水平与危重评分呈显著负相关，监测患儿PCT改变有助于评估脓毒症严重程度、疗效和预后。

Objective To evaluate the value of serum procalcitonin （PCT） measurement on diagnosis of sepsis in children. Methods From Mar. to Dec. 2005, 62 patients in our pediatric intensive care unit （ PICU ） with mean age of （4.6 ± 1.2 ） years old （ range 1 month to 11 years） were divided into sepsis group （S, n =30） and non -sepsis group （N, n =32） according to the 2005 definition for sepsis. Furthermore, the sepsis group was divided into severe （ SS, n = 11 ） and mild （ SM, n = 19 ） groups. Patients＇ severity was checked according to a domestic scoring system. Within 24 hours of hospitalization, serum PCT, C reactive protein （CRP）, white bloed cell （WBC）, bloed gas and pathogenic microorganisms were measured. Results Levels of PCT, CRP and WBC in S group were significantly higher than those in N group（Pa 〈0.01 ）. No differences were found in gender and age between the two groups. When PCT≥2.2 μg/L was applied as optimal cut-off values in diagnosing sepsis, its sensitivity, specificity, positive predictive value, negative predictive value were 96.7%, 87.5%, 87.9% and 96.5% ,respectively, and area under receiver operating characteristic （ROC） curve was 0. 992 ; when CRP≥25 mg/L was applied, the values were 83% , 75% , 75.8% , 82.8% and 0. 796, respectively; and when WBC≥13.09 × 10^9/L was applied, the values were 53 %, 75 %, 69.6%, 64.1% and 0.651, respectively. The PCT level was inversely correlated to patients＇ severity score （ r = - 0. 64 P 〈 0.01 ）. The PCT level in SS group was higher than that in SM group （ P 〈 0.01 ）. There were no differences in the levels of CRP and WBC between the two groups. Conclusion PCT may be a more sensitive serologic marker than WBC and CRP in differential diagnosis of sepsis. As there was an inverse correlation between PCT and severity score, PCT may be helpful to evaluate the severity of illness, therapeutic effect and prognosis in pediatric patients with sepsis.