纸片法与培养发酵法检测大肠菌群结果对比分析

Comparison of results of slip method with culture ferment method in detection of E.coli

目的探讨改进纸片法检测大肠菌群的判断标准。方法对纸片法检测大肠菌群的纸片反应结果状况进行详细记录后,将纸片以无菌操作转入单料乳糖胆盐发酵管中,用发酵法来证实其大肠菌群的阴阳性结果,再作统计分析。结果按GB14934-94判断纸片法大肠菌群的阴阳性,其灵敏度为73.3%,特异度为99.2%;若按作者提出的标准进行判断,其灵敏度为97.9%,特异度为90.3%。二者比较灵敏度有显著性差异(P<0.05)。消毒剂的残留可能是导致纸片法结果判断出偏差的主要原因。结论据本实验结果分析,建议改进和完善纸片法大肠菌群的判断标准,以更准确地反映大肠菌群检出的真实情况。

Objective To compare the slip method with culture ferment method in the detection of E. coli and for improving the accuracy of judgment of detection results. Methods Slip method was used for monitoring the contamination status of cooking utensils and the slips were put into lactose bile salts broth tubes for confirmation of the detection results by using ferment method. The re- sults were statistically analyzed. Results Based on the judgment standard of GB14934 - 94, the sensitivity and specificity of the slip method were 73.3% and 99.2% respectively. But the sensitivity and specificity were, based on the standard proposed by the author, 97.9% and 90.3%, respectively. The difference of the sensitivities was significant （ P 〈 0.05）, and the main cause of difference in judgment of the results was the residual of the disinfectant. Conclusion Thus it is suggested that the standard for judgment of results in detection of E. coli be modified so as to improve the accuracy of detection.