呼吸重症监护病房多药耐药菌定植与感染的临床鉴定分析

Clinical identification and analysis of colonization and infection with multidrug-resistant bacteria in patients in a respiratory intensive care unit

目的临床鉴定呼吸重症监护病房多药耐药菌定植与感染,指导临床疾病预防和治疗。方法收集322例医院呼吸重症监护病房患者临床资料,检测患者机械通气时间、APACHEⅡ评分、住院时间及VAP发生情况。对患者进行黏膜活检和定量培养,分析结果。结果从322例呼吸重症监护病房患者中分离多药耐药菌113株,其中鲍曼不动杆菌、铜绿假单胞菌、肺炎克雷伯菌、金黄色葡萄球菌、大肠埃希菌、其他多药耐药菌分别为42、28、23、12、3和5株。不同性别定植组和感染组患者间,差异无统计学意义(χ2=0.0129,P=0.909 7);不同年龄定植组和感染组患者间,差异有统计学意义(χ2=7.543 5,P=0.006 0)。感染组患者机械通气时间比定植组患者时间长(t=46.981,P=0.000);感染组患者住院时间比定植组患者时间长(t=40.101,P=0.000);感染组患者APACHEⅡ评分比定植组患者评分高(t=10.837,P=0.000)。230例定植组患者VAP发生率46.09%(106/230);92例感染组患者VAP发生率为31.52%(29/92),差异有统计学意义(χ2=5.7257,P=0.0167)。黏膜活检的特异性、灵敏度、阴性预测值、阳性预测值分别为76.41%、100.00%、100.00%和67.71%;定量培养的特异性、灵敏度、阴性预测值、阳性预测值分别为91.960%、82.270%、90.450%和100.000%;两者合用的特异性、灵敏度、阴性预测值、阳性预测值分别为80.44%、100.00%、100.00%和69.14%。结论呼吸重症监护病房多药耐药菌分布以鲍曼不动杆菌常见,住院时间和机械通气时间长的患者发生多药耐药菌感染几率更高。APACHEⅡ评分、VAP发生情况对鉴别多药耐药菌定植与感染有一定的指示作用。黏膜活检和定量培养合用对感染和定植的鉴别具有重要意义。

Objective To clinically identify colonization and infection with multidrug-resistant bacteria in patients in a respiratory intensive care unit in order to guide the prevention and treatment of disease in clinical settings. MethodsClinical data on 322 patients in a respiratory intensive care unit were collected to determine the time on mechanical ventilation,the APACHE II grade,the duration of hospitalization,and the incidence of VAP.A mucosal biopsy was performed,samples were quantitatively cultured,and the results were analyzed. Results One hundred and thirteen strains of multidrug-resistant bacteria were isolated from 322 patients in a respiratory intensive care unit.Of the 113 strains,42 were Acinetobacter baumannii,28 were Pseudomonas aeruginosa,23 were Klebsiella pneumonia,12 were Staphylococcus aureus,3 were Escherichia coli,and 5 were some other bacterium.Patients with bacterial colonization and patients with a bacterial infection did not differ significantly by sex（χ2=0.0129,P=0.9097）.Patients with bacterial colonization and patients with a bacterial infection differed significantly by age（χ2=7.5435,P=0.0060）.The time on mechanical ventilation for patients with a bacterial infection was longer than that for patients with bacterial colonization（t=46.981,P=0.000）.The same was true for the duration of hospitalization（t=40.101,P=0.000）and the APACHE II grade（t=10.837,P=0.000）.The incidence of VAP was 46.09%in 230 patients with bacterial colonization and 31.52%in 92 patients with a bacterial infection.The incidence of VAP differed significantly in the 2 groups（χ2=5.7257,P=0.0167）.Mucosal biopsies had a specificity of 76.41%,a sensitivity of 100.00%,a negative predictive value of100.00%,and a positive predictive value of 67.71%.Quantitative culturing had a specificity of 91.960%,a sensitivity of82.270%,a negative predictive value of 90.450%,and a positive predictive value of 100.000%.Both methods combined had a specificity of 80.44%,a sensitivity of 100.00%,a negative predictive value of 100.00%,and a positive predictive value of 69.14%. Conclusion Multidrug-resistant bacteria found in the respiratory intensive care unit were often A.baumannii,and the patients with a long duration of hospitalization and a long time on mechanical ventilation had a higher rate of infection with multidrug-resistant bacteria.The APACHE II grade and the incidence of VAP played a key role in distinguishing multidrug-resistant bacterial colonization and infection.Both mucosal biopsies and quantitative culturing significantly helped to distinguish between colonization and infection.