血清降钙素原在诊断老年肺部感染中的临床价值

目的探讨降钙素原（procalcitonin,PCT）在诊断老年肺部感染中的临床应用。方法回顾性调查分析民航总医院2009年5月至2013年4月4年间166例老年人群肺部感染患者的临床及其病原微生物资料,包括细菌性肺部感染（共92例,其中革兰阴性菌50例,革兰阳性菌42例）、肺念珠菌感染（12例）、活动性肺结核（11例）、肺炎支原体肺部感染（31例）及病毒性肺炎（20例）。同时选择参加体检的健康人群（12例）作为对照组,测定患者的血清PCT等实验室指标,采用非参数检验分析肺部感染各组之间的PCT质量浓度差异。结果与对照组相比,除病毒性肺炎与肺炎支原体感染组外,其余3组PCT质量浓度均显著升高（P肺结核组＆gt;肺炎支原体肺部感染组≈病毒性肺炎组≈对照组;ROC曲线分析表明PCT质量浓度在0.48 ng/mL与0.10 ng/mL的cut-off值时可分别较好鉴别细菌/念珠菌感染与肺结核/肺炎支原体肺部感染以及肺结核与肺炎支原体肺部感染。结论血清PCT质量浓度检测可为临床肺部感染的诊断提供重要的辅助手段,但应用中存在局限。

Clinical utility of serum procalcitonin in differentiation of pulmonary infections in the elderly populations

Objective To investigate the clinical utility of serum procalcitonin （ PCT ） in the diagnosis of pulmonary infections in elderly populations due to different pathogens .Methods A retrospective review was conducted by collecting the clinical data and microbiological records of 166 aged patients（≥60） having pulmonary infections from January 2009 to December 2011, including bacterial pneumonia（92 cases, 50 Gram-negative bacteria and 42 Gram-positive bacteria）, pulmonary candida infection （PC, 12 cases）, active pulmonary tuberculosis infection（TB, 11 cases）, Mycoplasma pneumoniae infection （MP, 31 cases）, and viral pneumonia（20 cases）. Furthermore, 12 healthy subjects who underwent the physical examination enrolled as the control group .The serum PCT levels and other biomarkers were determined .The non-parametric test was used to analyze the differences of PCT between the aforementioned groups while ROC curves to determine the best differentiating cut -off values .Results The PCT levels were significantly higher in all pulmonary infections but Mycoplasma pneumoniae than those in the control group （P〈0.01）.Moreover, the PCT levels in bacterial pneumonia and pulmonary candida infection indicated no significant difference （χ2=447.0, P=0.285）, however, its levels in bacterial pneumonia and PC groups were significantly higher than those in active TB and MP infection groups （χ2=308.5, P=0.012）.The changing trends of PCT concentrations in different groups were as follows：bacterial pneumonia≈PC〉active TB〉MP infection/viral infection≈control group .ROC curve indicated that at the cut-off values of 0.48 ng/mL and 0.10 ng/mL PCT could best differentiate bacterial pneumonia and PC from active TB and MP infection , respectively .Conclusion The serum PCT concentration , if at higher level , could be used as an effective means in differentiating pulmonary infections in the elderly populations , but if it was at slightly increased level , it might be caused by various microbiol