老年下呼吸道感染患者病原菌分布及耐药性分析

Distribution and drug resistance of pathogenic bacteria causing lower respiratory tract infections in senile patients

目的探讨青海地区藏族和汉族老年下呼吸道感染患者病原菌分布及耐药性特点与差异,为下呼吸道感染临床用药提供参考。方法分别采用VITEK-32全自动细菌鉴定仪和K-B纸片扩散法,对520例藏族和520例汉族老年下呼吸道感染患者下呼吸道痰和分泌物样本进行病原菌种类、分布和耐药性检测,比较分析两组患者原菌菌分布及耐药性的特点和区别。结果共分离出病原菌725株,其中革兰阴性菌占66.76%,革兰阳性菌占16.14%,真菌占17.10%;藏族患者检出革兰阴性菌占67.14%,革兰阳性菌占19.49%显著高于汉族(P<0.05),真菌为13.37%,显著低于汉族(P<0.05);亚胺培南对革兰阴性菌敏感性最好,耐药率在0～14.08%;氨曲南对革兰阴性菌敏感性最差,耐药率在45.71%～76.92%;藏族和汉族老年下呼吸道感染患者主要革兰阴性菌对亚胺培南和氨曲南耐药性差异有统计学意义(P<0.05)。结论青海藏族和汉族老年下呼吸道感染患者病原菌以革兰阴性菌为主,但病原菌分布及耐药性存在民族间差异,临床应根据药敏结果合理选用抗菌药物。

OBJECTIVE To explore the distribution and drug resistance of pathogenic bacteria causing lower respiratory tract infections in the senile patients of Tibetan and Han in Qinghai so as to guide the clinical medication for treatment of lower respiratory tract infections. METHODS The VITEK-32 automatic bacterial identification system and the K-B disk diffusion method were respectively employed to detect the species of pathogens that were isolated from the lower respiratory tract sputum and secretions obtained from 520 senile patients of Tibetan and 520 senile patients of Han, then the characteristics of the distribution of pathogens and the drug resistance were analyzed and compared. RESULTS Totally 725 strains of pathogenic bacteria were isolated, among which the gram-negative bacteria accounted for 66.76%, gram-positive bacteria 16.14%, fungi 17.10% 67.4% of the gram-negative bacteria and 19.49 % of the gram-positive bacteria were isolated from the Tibetan patients, significantly higher than those from the Han patients （P〈 0. 05） ~ 13. 37 % of the fungi were isolated from the Tibetan patients, significantly lower than that from the Han patients （P^0.05）. The gram-negative bacteria were most susceptible to imipenem, with the drug resistance rate varying between 0 and 14, 08% ; the gram-negative bacteria were least susceptible to aztreonam, with the drug resistance rate varying between 45.71% and 76.92%. The difference in the drug resistance of the main gram-negative bacteria isolated from the senile patients of Tibetan and Han to imipenem or aztreonam was significant （P〈0. 05）. CONCLUSION The gram- negative bacteria are the predominant pathogens causing the lower respiratory tract infections in the senile patients of Tibetan and Han in Qinghai, but there is difference in the distribution of pathogens or the drug resistance between the two ethnics, it is necessary to reasonably use antibiotics based on the result of drug susceptibility testing.