• Users Online: 116
  • Home
  • Print this page
  • Email this page
Year : 2015  |  Volume : 4  |  Issue : 5  |  Page : 110

Utility of Line Probe Assay for diagnosis of extrapulmonary tuberculosis

1 Department of Pathology and Microbiology, Aga Khan University, Karachi, Pakistan
2 Clinical Laboratories, Aga Khan University, Karachi, Pakistan

Correspondence Address:
Joveria Farooqi
Department of Pathology and Microbiology, Aga Khan University, Karachi
Login to access the Email id

Source of Support: None, Conflict of Interest: None

Rights and PermissionsRights and Permissions

Introduction: In 2008, the World Health Organization (WHO) approved a rapid molecular test known as Line Probe Assay (LiPA) for the diagnosis of multidrug-resistant tuberculosis (MDR-TB) in pulmonary specimens. Due to lack of available data, its use in extra-pulmonary tuberculosis (EPTB) specimens has not been determined yet. Recommendations for the use of Xpert MTB/RIF in EPTB have been issued, but alternative rapid molecular tests for EPTB diagnosis need to be evaluated. Method: LiPA (GenoType® MTBDRplus 2.0 Hain Lifescience) was performed on 97 specimens of extrapulmonary origin at the clinical laboratory at Aga Khan University (Dec 2012–Jan 2014). The results were compared with TB cultures in solid and liquid medium. Results: 97 specimens were tested simultaneously for culture and LiPA, including pleural fluid (35), CSF (22), pus (17), tissue (10) and urine (3). Concentrated smear was positive for 7 while 14 were culture positive for MTB. All 7/7 smear-positive specimens were LiPA positive, while 6/7 were culture positive. Amongst the smear-negative specimens, 8/90 were culture positive and 9/90 were LiPA positive. The overall sensitivity and specificity of LiPA for the detection of MTB in the EPTB specimens was 71.4% (95% CI 41.9–91.4) and 92.8% (95% CI 84.9–97.3), respectively. The highest sensitivity (100%) was seen in urine as 2 of 3 which were culture positive were also LiPA positive. Pus samples showed sensitivity of 85.7% and specificity of 70%. Conclusion: The study shows that LiPA has good overall sensitivity and specificity compared with culture. Although the number of samples was very small, the applicability appears to be most useful in urine and pus specimens and should be explored further as a diagnostic tool in these cases.

Print this article     Email this article
 Next article
 Previous article
 Table of Contents

 Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
 Citation Manager
 Access Statistics
 Reader Comments
 Email Alert *
 Add to My List *
 * Requires registration (Free)

 Article Access Statistics
    PDF Downloaded65    
    Comments [Add]    

Recommend this journal