应用国产仪器对血培养阳性标本直接细菌鉴定和药敏实验的探讨

Positive blood culture specimens for direct bacteria identification and drug susceptibility test with domestic instrument

目的探讨应用国产仪器细菌鉴定和药敏系统对血培养阳性标本进行直接鉴定药敏试验的应用价值。方法选取2015年3—12月石家庄市白求恩国际和平医院患者血培养阳性标本200例,以手工法为参考标准,常规法和直接法进行细菌鉴定和药敏试验,统计直接法鉴定的正确率、未鉴定率及错误率,药敏试验的正确率、错误率及有误差率,并与常规法相比较。结果 200例标本共检测到G-杆菌95株,G+球菌105株。常规法鉴定G-杆菌与直接法相比,正确率(87.37%,85.26%)、未鉴定率(8.42%,9.47%)、错误率(4.21%,5.26%)差异均无统计学意义。常规法鉴定革兰氏阳性球菌与直接法相比,正确率(86.67%,84.76%)、未鉴定率(10.48%,11.43%)、鉴定错误率(2.86%,3.81%)差异均无统计学意义。常规法G-杆菌的药敏检测与直接法相比,正确率(95.85%,94.42%),有误差率(3.28%,4.15%),错误率(0.87%,1.42%)差异均无统计学意义。常规法G+球菌的药敏检测与直接法相比,正确率(96.96%,89.94%)、有误差率(2.68%,7.62%)、错误率(0.36%,2.44%)差异有统计学意义(χ~2=67.72,P=0.00;χ~2=41.98,P=0.00;χ~2=26.43,P=0.00)。结论应用国产自动细菌鉴定和药敏系统对血培养阳性标本进行直接鉴定药敏实验,结果可靠,快速,经济,可在临床推广应用。

Objective To explore the efficacy of direct identification and susceptibility testing for positive blood cultures with a home-made micro-organism identification and susceptibility system. Methods Two hundred positive blood culture samples were collected from the bethune international peace hospital between March and December 2015. The identification and susceptibility testing was carried out using a manual method, routine method and direct method. The correct rate, miss rate, and error rate of the susceptibility testing with the routine method and direct method were analyzed and compared. Results A total of 95 strains of G bacilli and 105 strains of G~ coccus were detected from 200 samples. G- bacillus and G＋ coccus identified by the routine method were compared with those by the direct method. There was no significant difference in the correct rate （87.37%, 85.26%）, miss rate （8.42%, 9.47%） and error rate （4.21%,5.26%） of G- bacillus detection between these two methods. There was also no significant difference in the correct rate （86.67%,84.76%）, miss rate （10.48%, 11.43%）, and error rate （2.86%,3.81%） of G＋ coccus detection between the two groups. The results of susceptibility testing of G- bacilli were not significantly different between the routine method and the direct method, for the correct rate was 95.85% and 94.42%, miss rate 3.28% and 4.15%, and error rate was 0.87% and 1.42% respectively. There was, however, significant difference in the results of the susceptibility testing of G~ coccus between the routine method and the direct method, for the correct rate was 96.96% and 89.94% （Z2=67.72, P=0.00）, miss rate 2.68% and 7.62% （Z2=41.98, P=0.00）, and error rate was 0.36% and 2.44% （Z2=26.43, P=0.00） respectively. Conclusion The use of positive blood cultures for direct identification and susceptibility testing with a home-made micro-organism system can provide quick and accurate results at a low cost, which can be widely used clinically.