聚合酶链反应在肺结核和肺外结核诊断中的重要性。

Importance of polymerase chain reaction in diagnosis of pulmonary and extra-pulmonary tuberculosis.

作者信息

Iqbal Sajjad, Ahmed Rashid, Adhami Saleem-uz-Zaman, Mumtaz Asim

机构信息

Department of Pathology, Shalimar Hospital, Shalimar Link Road Mughalpura, Lahore, Pakistan.

出版信息

J Ayub Med Coll Abbottabad. 2011 Jan-Mar;23(1):73-6.

PMID:22830152

Abstract

BACKGROUND

Pakistan ranks 8th on the list of 22 high-burden tuberculosis (TB) countries in the world according to the World Health Organization's (WHO) Global Tuberculosis Control 2009. Including other reasons the main cause is improper and late diagnosis of the disease. PCR may play an important role to control the disease with its rapid, sensitive and specific diagnosis. But in Pakistan due to lake of knowledge about this latest technique we are not using this technique appropriately. Clinicians still trust on conventional methods of TB diagnosis, which are time consuming or insensitive. The present study was arranged to highlight the importance of PCR in TB diagnosis in pulmonary and extra-pulmonary cases and its comparison with conventional methods.

METHODS

Samples obtained from 290 patients of suspected TB (pulmonary or extra-pulmonary) were subjected to ZN smear examination, LJ medium culture and PCR test by amplifying 541bp fragment of Mycobacterium tuberculosis complex genome. The present prospective study is performed at Shalamar Hospital Lahore from November 2008 to November 2010.

RESULTS

A distinctly difference was observed in the test results done by PCR and other conventional techniques in pulmonary or extra-pulmonary tuberculosis samples (p<0.001). The sensitivity of different tests was 68.62% for PCR, 26.90% for LJ medium culture, and 14.14% for ZN smear examination (p<0.05). However, there was no significant difference between different tests as for as specificity was concerned. PCR test sensitivity in pulmonary and extra-pulmonary clinical samples was 78.34 and 61.76% respectively, being significantly higher (p<0.05) when compared with sensitivity of other tests. The mean detection time for M. tuberculosis was 25 days by LJ medium culture and less than 1 day by smear examination and PCR test.

CONCLUSION

PCR test is more sensitive than ZN smear examination and LJ medium culture for the diagnosis of TB in pulmonary and extrapulmonary clinical samples.

摘要

背景

根据世界卫生组织（WHO）《2009年全球结核病控制报告》，巴基斯坦在全球22个结核病高负担国家中排名第8。包括其他原因在内，主要病因是对该疾病诊断不当和诊断延迟。聚合酶链反应（PCR）凭借其快速、灵敏和特异的诊断能力，可能在控制该疾病方面发挥重要作用。但在巴基斯坦，由于对这项最新技术缺乏了解，我们并未恰当地使用该技术。临床医生仍信赖结核病诊断的传统方法，而这些方法既耗时又不灵敏。本研究旨在强调PCR在肺结核和肺外结核病例诊断中的重要性，并将其与传统方法进行比较。

方法

从290例疑似结核病（肺结核或肺外结核）患者中获取样本，通过扩增结核分枝杆菌复合基因组的541bp片段，进行萋-尼涂片检查、罗氏培养基培养和PCR检测。本前瞻性研究于2008年11月至2010年11月在拉合尔的沙勒马医院开展。

结果

在肺结核或肺外结核样本中，PCR与其他传统技术的检测结果存在显著差异（p<0.001）。不同检测方法的敏感度分别为：PCR为68.62%，罗氏培养基培养为26.90%，萋-尼涂片检查为14.14%（p<0.05）。然而，就特异性而言，不同检测方法之间无显著差异。PCR检测在肺结核和肺外结核临床样本中的敏感度分别为78.34%和61.76%，与其他检测方法的敏感度相比显著更高（p<0.05）。结核分枝杆菌的平均检测时间，罗氏培养基培养为25天，涂片检查和PCR检测均少于1天。