痰液及血清降钙素原联合检测在婴幼儿社区获得性肺炎中的应用

目的通过对社区获得性肺炎（community acquired pneumonia, CAP）婴幼儿联合检测痰液及血清降钙素原（procalcitonin，PCT），探讨其在鉴别婴幼儿CAP病原学性质方面的意义。方法2010年8月至2012年9月我院儿科病房婴幼儿CAP病原学诊断明确的435例恩儿，根据病原性质分为3组：细菌感染组243例（混合细菌感染归人此组），病毒感染组106例，肺炎支原体感染组86例。比较分析痰液及血清PCT水平，同时检测血常规白细胞、C反应蛋白。结果细菌感染组CAP患儿痰液PCT（8．44±1．08）ng／ml，明显高于病毒感染组（0.32±0.12）ng／ml和支原体感染组（0．24±0.17）ng／ml，差异有统计学意义（F=765．03，P〈0．01）；血清PCT检测水平细菌感染组（6．69±1．36）ng／ml，亦高于病毒感染组（0．37±0．22）ng／ml及支原体感染组（0．42±0．28）ng／ml，差异有统计学意义（F=240．46，P〈0．01）；而病毒感染组与支原体感染组间痰液PCT、血清PCT比较差异无统计学意义（P〉0．05）。3组患儿血常规白细胞、C反应蛋白水平比较差异无统计学意义（P〉0．05）。以痰液、血清PCT〉0．5ng／ml为临界值，细菌感染组痰液、血清PCT阳性率比较差异有统计学意义（86．83％vs73．66％，x^2=13．92，P〈0．05）。痰液、血清PCT诊断婴幼儿细菌性CAP的敏感性分别为86．83％和73．66％，特异性分别为86．98％和88．54％，联合检测痰夜、血清PCT的敏感性、特异性分别为72．02％和94．27％。结论联合检测痰液及血清PCT，对明确婴幼儿CAP病原体性质更具临床价值。

Application of combined detection of sputum and serum procalcitonin in infants with community acquired pneumonia

Objective To evaluate the effects of combined detection of sputum and serum procalcitonin （PCT） to identify the etiology of community acquired pneumonia（CAP） in infants. Methods Retro- spective analysis from August 2010 to September 2012 enrolled 435 patients with definitely etiological diagnosis of CAP. The all cases were divided into three groups according to the etiological diagnosis ：243 cases of bacterial infection group（ including mixed bacterial infection）, 106 cases of viral infection group, and 86 cases of mycoplasma infection group. Sputum and serum PCT levels in all cases were detected, with simultaneous detection of blood leukocytes, C-reactive protein levels. Results Sputum PCT level of bacterial infection group [ （8.44 ±1.08） ng/ml] was significantly higher than viral infection group E （0. 32 ±0. 12） ng/ml] and mycoplasma infection group [（ 0. 24 ±0. 17 ） ng/ml ], which showed statistically significant difference （ F = 765.03 ,P 〈0. 01 ）. Serum PCT level of bacterial infection group [ （6. 69 ±1.36） ng/ml] was also higher than viral infection group [ （0. 37 ±0. 22 ） ng/ml ] and mycoplasma infection group [ （ 0. 42 ±0. 28 ） ng/ml ], the difference of which was statistically significant （ F = 240. 46, P 〈 0. 01 ）. Meanwhile between the viral infection group and mycoplasma infection group, sputum PCT and serum PCT showed no significant difference （P 〉 0. 05）. The levels of blood leukocytes and C-reactive protein among 3 groups showed no statistically significant difference（P 〉 0. 05）. As the critical value of the PCT 〉 0. 5ng/ml, the positive rates of sputum and serum PCT were significant difference in bacterial infection group （86. 83% vs 73.66%, x2 = 13.92, P 〈0.05 ）. The sensitivity of diagnosing bacterial CAP by sputum and serum PCT levels were 86. 83% and 73.66%, the specificity were 86. 98% and 88.54% ,respectively. The sensitivity and specificity of combined detection sputum and serum PCT were 72. 02% and 94. 27%. Conclusion Combined detection of sputum and serum PCT has clinical value and efficiency in pathogen identification of CAP.