结核性脑膜炎患者中几种病原诊断检测技术的应用

Utility of several methods for etiological diagnosis in patients with tuberculous meningitis

目的探讨不同病原学检测方法在结核性脑膜炎(结脑)临床诊断中的应用。方法对临床诊断为结脑患者60例(结脑组)和非结脑患者70例(非结脑组)的脑脊液标本,同时进行离心涂片抗酸染色、结核菌BACTEC MGIT 960快速培养、实时荧光定量聚合酶链反应(FQ-PCR)、玻片离心改良抗酸染色检测,并对其结果进行比较分析。结果结脑组标本中,涂片抗酸染色、结核菌快速培养、FQ-PCR检测、玻片离心改良抗酸染色法的检出率分别为11.7%(7/60)、6.7%(4/60)、48.3%(29/60)、61.7%(37/60)。非结脑组中2例玻片离心改良抗酸染色阳性。玻片离心改良抗酸染色法检出率高于其他3种检测方法,差异有统计学意义(P<0.05),且能发现细胞内抗酸杆菌,应用该种方法检测,4例结核菌培养阳性患者的8份脑脊液标本均为阳性。结论玻片离心改良抗酸染色法操作简便、快速,可明显提高脑脊液中抗酸杆菌的检出率,既能检出细胞外抗酸杆菌,也可检出细胞内抗酸杆菌,此方法可能有助于提高病原检测的阳性率,值得进一步探讨其在结脑早期诊断中的临床意义。

Objective To examine the clinical utility of four methods in diagnosis of tuberculous meningitis. Methods A total of 60 patients with tuberculous meningitis were included as study group and another 70 patients with non-tuberculous intracranial infection as control group. Four methods, including conventional acid fast stain, Myobacterium tuberculous culture in BACTEC MGIT 960, real-time fluorescent quantitative polymerase chain reaction （FQ-PCR） and modified acid fast stain, were used to assay the cerebrospinal fluid specimens for diagnosis oftuberculous meningitis. Results The positive rate was 11.7%（7/60）,6.7%（4/60）, 48.3% （29/60）, and 61.7% （37/60）, respectively in the study group as tested by the four methods. There was significant difference between the four methods in the positive rate （P 〈 0.05）. Modified acid fast stain was more sensitive than the other 3 methods in identifying tuberculous meningitis （P 〈 0.05）. This method also could identify the intracellular M. tuberculosis. All the 8 samples from the 4 patients who were positive for culture of M. tuberculosis were positive in the modified acid fast stain. Conclusions The modified acid fast staining method is simple, fast, significantly more senstive in detection of the acid fast M. tuberculosis in CSF, either extracellular or intracellular. It is worthwhile to further investigate its usefulness in early diagnosis of tuberculosis meningitis.