皮肤结核实验室检测方法的比较研究

The comparative study of laboratory detection methods on cutaneous tuberculosis

目的比较和分析涂片抗酸染色法(AFS)、γ-干扰素(IFN-γ)释放试验(TB-IGRA)、实时荧光定量PCR(qRT-PCR)、TB-IGRA联合基因芯片法(TB-IGRA-GC,GC基因芯片法检测分枝杆菌菌种及耐药基因)在皮肤结核实验室诊断中的性能,筛选较为准确诊断皮肤结核的实验室方法。方法以34例皮肤结核病患者为阳性对照组,16例非皮肤结核住院患者为阴性对照组。比较AFS、TB-IGRA、qRT-PCR及TB-IGRA-GC检测皮肤结核的敏感性及菌种鉴定和耐药基因检测,并进行统计学分析和评价。结果 TB-IGRA-GC与TB-IGRA法检测皮肤结核的敏感性均为88.2%,qRT-PCR法与AFS法的敏感性分别为82.4%和23.5%,TB-IGRA-GC、TB-IGRA、qRT-PCR与AFS在灵敏度上相比均有显著差异(P<0.05)。TB-IGRA-GC在50例标本中共检测出结核分枝杆菌复合群30例,非结核分枝杆菌1例(金色分枝杆菌)。30例结核分枝杆菌阳性标本耐药基因检测显示有3例发生耐药基因突变,其中2例为利福平耐药,1例为异烟肼耐药,没有检测到多重耐药菌株。结论 TB-IGRA-GC在皮肤结核诊断上具有简便快速、灵敏度高、特异性好的优点,同时能进行分枝杆菌菌种鉴定和耐药基因检测,更有利于皮肤结核的发现、防控以及准确治疗,可作为临床皮肤结核实验室诊断的常规标准方法。

Objective To analyze and compare the laboratory detection methods of cutaneous tuberculosis,including smear acid-fast stain（AFS）,interferon-gamma release assay（TB-IGRA）,real-time quantitative polymerase chain reaction（qRT-PCR）,TB-IGRA combined with gene chip（TB-IGRA-GC,GC identification of mycobacterium and detection of drug-resistant genes by gene chip）and discuss their clinic efficacy,and select the most reasonable laboratory diagnosis method for cutaneous tuberculosis.Methods 34 cutaneous tuberculosis patients were used as positive control.16 noncutaneous tuberculosis patients were used as negative control.Collecting the information about the sensitivity and identification of mycobacterium and the drug-resistant genes detecting of AFS,TB-IGRA,qRT-PCR,TB-IGRA-GC,and then statistically analyzed and compared the results of the four groups.Results The results showed that the sensitivity of TB-IGRA-GC and TB-IGRA for the detection of cutaneous tuberculosis were both 88.2%,But qRT-PCR and AFS were82.4% and 23.5%.There were significant differences between AFS and other methods（P0.05）.Among the 50 cases,TB-IGRA-GC found that 30 cases were mycobacterium tuberculosis complex.1case was nontuberculous mycobacteris（Mycobacteria aurum）.30 Mycobacterium positive samples showed drug-resistant genes.3cases showed drug-resistant genes mutation.2cases were rifampicin.1case was isoniazid.The multiple resistant strains were not detected.Conclusion Compared with AFS,TB-IGRA,qRT-PCR and TB-IGRA-GC are the most convenient,rapid,sensitive and specificity laboratory method for diagnosing cutaneous tuberculosis.Meanwhile,they can identify the mycobacterium strains and detect drug resistance gene.This is conducive to detect,prevent and treat cutaneous tuberculosis.