探讨血浆降钙素原（PCT）、C-反应蛋白（CRP）水平及白细胞（WBC）计数联合检测在呼吸道感染诊断中的临床意义。

选取2013年7月至2014年4月于本院就诊的呼吸道感染者共104例，按照是否伴有细菌感染分组，选取同期健康体检者40例作为对照组，比较两组研究对象血浆PCT、CRP水平和WBC计数的差异，计算各指标联合检测对呼吸道细菌感染的诊断效率。

细菌感染组患者血浆PCT、CRP水平和WBC计数较非细菌感染组患者均显著升高，差异具有统计学意义（t = 9.316、8.389、8.495，P均= 0.000）；三者联合检测的敏感度与PCT、CRP、WBC检测差异均具有统计学意义（χ² = 30.687、21.682、22.753，P均= 0.000），联合检测的特异度与CRP、WBC检测差异均具有统计学意义（χ² = 11.665、11.665，P均= 0.000）。

PCT、CRP水平和WBC计数联合检测能够有效地提高临床对于呼吸道感染的诊断率，同时有利于对细菌性感染的准确判定，亦为临床合理用药提供了一定的依据。

To investigate the clinical significance of combined detection for the levels of plasma procalciton (PCT), C-reaction protein (CRP) and counts of white blood cell (WBC) in diagnosis for respiratory tract infection.

Total of 104 patients with respiratory tract infections in our hospital from July 2013 to April 2014 were selected and divided into two groups according to with or without bacterial infection, while 40 healthy adults were selected as control group. The differences of levels of PCT, CRP and counts of WBC were compared between the two groups, respectively. The clinical efficiency of each index of combined detection for diagnosis of respiratory tract bacterial infections was calculated.

The levles of PCT, CRP and counts of WBC in patients with bacterial infection were increased significantly than patients with non-bacterial infection (t = 9.316, 8.389, 8.495; P all = 0.000). The sensitivity of combined detection was compared with PCT, CRP and WBC detection, with significantly differences (χ² = 30.687, 21.682, 22.753; P all = 0.000). Compared specificity of combined detection was compared with CRP and WBC detection, the differences were significant (χ² = 11.665, 11.665; P all = 0.000).

The combined detection of levels of PCT, CRP and counts of WBC could effectively improve the clinical diagnosis rate for respiratory tract infection, and it was conducive to the judgment of bacterial infection and could provide related evidence for clinical rational drug application.