老年重症肺炎患者病原学分布及死亡危险因素分析

Pathogenic distribution and risk factors of death in elderly patients with severe pneumonia

目的探讨老年重症肺炎(SP)患者病原学分布特征及影响其死亡的相关危险因素。方法选取2013年1月至2016年9月儋州市人民医院诊断为老年重症肺炎患者316例,根据治疗结束后48 h内患者的生存状况将其分为存活组215例和死亡组101例。对316例老年重症肺炎患者进行痰培养检查,采用法国生物梅里埃VITEK2全自动细菌分析仪分离和鉴定菌株,并观察病原菌耐药情况。应用单因素及多因素Logistic回归分析老年重症肺炎患者死亡的危险因素,并绘制ROC曲线分析各危险因素预测老年重症肺炎患者死亡的价值。结果 316例SP患者共分离出病原菌291株,其中革兰阴性菌占70.79%,革兰阳性菌占20.27%,真菌占8.94%。死亡组感染铜绿假单胞菌、鲍曼不动杆菌、金黄色葡萄球菌及混合菌患者人数明显高于存活组(P<0.001)。药敏结果显示,铜绿假单胞菌和鲍曼不动杆菌对亚胺培南、阿米卡星和环丙沙星敏感,而对头孢唑林、头孢呋辛和氨苄西林耐药率较高;溶血性葡萄球菌对万古霉素和亚胺培南敏感性较高,而对哌拉西林不敏感,耐药率高达83.33%;肺炎链球菌对头孢唑林和亚胺培南最敏感,而对青霉素和庆大霉素相对不敏感,耐药率分别为53.85%、61.54%。Logistic回归分析显示,呼吸衰竭、机械通气、Alb水平低、APACHEⅡ评分高、CPIS评分高、CRP水平高是老年重症肺炎患者死亡的独立危险因素(P<0.05)。ROC曲线显示,Alb、APACHEⅡ评分、CPIS评分及CRP预测老年重症肺炎死亡的曲线下面积(AUC)及95%CI分别为:0.628(0.557~0.718)、0.752(0.683~0.835)、0.714(0.642~0.804)、0.806(0.734~0.891),其中CRP预测重症肺炎死亡的敏感度和特异度最好,分别为85.4%和74.6%。结论老年重症肺炎患者感染病原菌较广,耐药性也日趋严重,且影响死亡的危险因素较多,需采取相应措施,控制感染,提高患者的生存率。

Objective To investigate the pathogenic distribution characteristics and risk factors of death in elderly patients with severe pneumonia（SP）. Methods From January 2013 to September 2016, 316 elderly patients with SP were diagnosed in our hospital. According to the survival of the patients within 48 hours after the end of the treatment, the patients were divided into 215 cases of a survival group and 101 cases of a death group. The 316 elderly patients with SP were examined by sputum culture, and the isolation and identification of bacterial strains were performed by French bio Merieux VITEK2 automatic analyzer, and the drug resistance of pathogenic bacteria was observed. The univariate and multivariate logistic regression analyses were used to analyze the risk factors of death in the elderly patients with SP, and the ROC curve of the risk factors was drawn for predicting the value in death of elderly patients with SP. Results A total of 291 strains of pathogenic bacteria were isolated from 316 patients with SP, including 70.79% of gram negative bacteria, 20.27% of Gram-positive bacteria, and 8.94% of fungi. The number of patients infected with Pseudomonas aeruginosa, Acinetobacter bauman,Staphylococcus aureus and mixed bacteria in the death group was significantly higher than that in the survival group（P〈0.001）.The drug susceptibility results showed that Pseudomonas aeruginosa and Acinetobacter bauman were sensitive to imipenem,amikacin and ciprofloxacin, but resistant to cefazolin, cefuroxime and ampicillin. Hemolytic staphylococci was sensitive to vancomycin and imipenem, but not sensitive to piperacillin, and the resistance rate was as high as 83.33%. S treptococcus pneumoniae was the most sensitive to cefazolin and imipenem, and relatively insensitive to penicillin and gentamicin, and the resistance rates were 53.85% and 61.54% respectively. The logistic regression analysis showed that respiratory failure,mechanical ventilation, low level of Alb, high APACHE II score, high CPIS score, and high CRP level were the independent risk factors of death in elderly patients with SP（P〈0.05）. The ROC curve showed that Alb, APACHE score, CPIS score and CRP predicted the area under the curve（AUC） and 95%CI of death in elderly patients with SP were 0.628（0.557-0.718）,0.752（0.683-0.835）, 0.714（0.642-0.804）, and 0.806（0.734-0.891） respectively, and among them, CRP had the best prediction of SP death and the sensitivity and specificity were 85.4% and 74.6% respectively. Conclusion The infection pathogenic bacteria is more extensive in the elderly patients with SP, the drug resistance is also becoming more and more serious, and the risk factors of death are also more, therefore, it is necessary to take appropriate measures to control the infection to improve the survival rate of the patients..