显微镜检查痰中结核分枝杆菌最低检测限的统计推断及方法改进

Statistical interference of lowest detection limit for mycobacterium tuberculosis in sputum by microscopic examination

目的利用模拟痰标本,评价直接涂片和"液化集菌"镜检痰中结核分枝杆菌的最低检测限。方法对不同稀释度的模拟痰标本"液化集菌"前后分别进行涂片和采用冷冻及室温存放载玻片滴片,并分别进行ZN和金铵O染色。直接涂片进行ZN和金铵O染色的结果分别命名为A、B组结果;采用冷冻载玻片ZN染色和金铵O染色的结果分别命名为C、D组结果;室温存放载玻片滴片ZN染色的结果命名为E组结果。结果 A/B/C/D四组涂(滴)片所对应的NC A-D均未检出结核分枝杆菌;A组涂片有2片次106稀释度和4片次107稀释度未检出结核分枝杆菌,合计6片次(6/54,11.11%);B/C/D三组涂(滴)片未出现未检出结核分枝杆菌的结果,但B组涂片结果为实际条数描述1+、2+、3+、4+的片次数分别为7、23、13、5、6,而C/D两组滴片分别为5、19、16、6、8和1、4、20、18、11。结论 "液化集菌"处理痰标本可以提高痰涂片检查结核分枝杆菌的敏感性,应用金铵O染色和LED显微镜检查进一步扩大了这一优势,采用冷冻后的载玻片滴片可以改善沉渣膜脱落现象,值得进一步进行研究分析。

Objective Using the simulated sputum specimen to evaluate the lowest detection limit of mycobacterium tuberculosis in sputum by direct smear and ＂liquefaction set bacteria＂ microscopy. Methods The simulation sputum specimens with different dilution were treated with direct smear, frozen object slide and object slide storage at room temperature before and after ＂liquefaction set bacteria＂ respectively, then ZN dyeing and gold ammonium O dyeing were conducted on these sputum specimens. The ZN dyeing and gold ammonium O dyeing results were named as A, B group in specimens by direct smear, those of frozen slide were named as C, D group, and those of room temperature storage slide drop piece were named as E group, then the results were statistically analyzed. Results The NCA-D corresponding to smear （drop） piece in A/B/C/D groups were not detected mycobacterium tuberculosis. In A group, two pieces of smears with 10^6 - time dilution and 4 pieces of smears with 10^7 - time dilution were not detected mycobacterium tuberculosis, 6 pieces in total （6/54,11.11% ） ; In B/C/D groups, mycobacterium tuberculosis was not detected, but group B smear results showed the numbers of sc, 1 ＋, 2 ＋ ,3 ＋ , 4 ＋ were 7, 23, 13, 5, 6, and those in C/D groups were 5, 19, 16, 6, 8 and 1,4, 20, 18, 11. Conclusion Liquefaction set bacteria application in sputum specimens can improve the sensitivity of mycobacterium tuberculosis detection, and the application of gold ammonium O dyeing and LED microscopy further expanded this advantage, because the freezing object slide can reduce sediment film falling, deserving further research and analysis.