结核性胸膜炎患者胸腔积液分枝杆菌检测结果分析

Analysis of results of mycobacteria detection in pleural effusion of patients with tuberculosis pleurisy

目的 ：通过分析结核性胸膜炎患者胸腔积液分枝杆菌检测结果,探讨提高其阳性检出率的方法。方法 ：采集267例临床诊断为结核性胸膜炎患者的胸腔积液,离心后弃上清,用氢氧化钠（Na OH）消化处理,磷酸盐缓冲液（PBS）中和离心,取沉淀涂片抗酸染色镜检,接种MGIT960系统培养管和罗氏培养基,分析培养和涂片镜检结果 ,采用χ~2检验比较抗酸杆菌涂片与分枝杆菌培养阳性率的差异,BACTEC MGIT 960系统与罗氏培养阳性率的差异。结果：267例结核性胸膜炎患者胸腔积液经消化处理后,抗酸杆菌涂片阳性者81例,阳性率为30.6%,涂片1~8条/300个视野至1＋以下者占涂片阳性的97.5%。罗氏培养233例,培养阳性39例,阳性率为16.7%,培养1＋以下者为97.4%。MGIT960系统培养221例,培养阳性72例,阳性率为32.6%。消化后涂片法阳性率高于罗氏培养法（χ~2=7.92,P〈0.01）,MGIT960系统培养阳性率高于罗氏培养阳性率（χ~2=11.30,P〈0.01）;MGIT960系统培养阳性率高于消化后涂片法（χ~2=0.31,P〉0.05）。结论：结核性胸膜炎患者胸腔积液中抗酸杆菌菌量少。胸腔积液经消化集菌可显著提高抗酸杆菌涂片阳性率。相比罗氏培养,MGIT 960系统能显著提高分枝杆菌培养的阳性率。

Objective To improve the detection rate of Mycobacterium tuberculous via analyzing the results of Mycobacterium tuberculosis detection in pleural effusion of patients with tuberculosis pleurisy by various methods. Methods Pleural effusion fluid was collected from 267 cases of tuberculous pleurisy. After centrifugation, the supernatant was dis-carded and the sendiment was digested with Na OH, then added phosphate-buffered saline（PBS）, centrifuged, and the precipitate was making smear for microscopic examination with acid-fast stain and was inoculated into MGIT960 culture system and Lowenstein-Jensen（LJ）medium. Analyzed the difference in positive rates between culture and smear microscopic examination and compared the positive rate of BACTEC MGIT 960 culture system with LJ medium. Results Of the 267 cases of tuberculous pleural effusion, 81 cases（30.6%） were smear-positive. LJ medium had been inoculated in 233 cases,39 cases were positive, the positive rate was 16.7%; 221 cases were inoculated into MGIT960 culture system and was posi-tive in 72 cases, the positive rate was 32.6%. After digestion, smear positive rate was higher than that of LJ medium（χ^2=7.92, P 〉0.01）. There was significant difference between the positive rate of the MGIT960 system and LJ medium（χ^2=11.30, P〉0.01）. The positive rate of MGIT 960 system was higher than that of smear（χ^2=0.31, P〉0.05）. Conclusions Acidfast bacillus was sparse in tuberculous pleural effusion. Centrifugation and digestion will greatly improve the smear-positive rate of acid-fast bacilli in pleural effusion. Compared to LJ medium, MGIT 960 culture system can significantly improve the positive rate of mycobacterial culture.