Effectiveness of an integrated real-time PCR method for detection of the Mycobacterium tuberculosis complex in smear-negative extrapulmonary samples in an area of low tuberculosis prevalence

J Clin Microbiol. 2012 Feb;50(2):513-5. doi: 10.1128/JCM.06467-11. Epub 2011 Dec 7.


Early extrapulmonary tuberculosis (EPTB) diagnosis is particularly difficult. Among 108 smear-negative extrapulmonary samples showing a positive culture for Mycobacterium tuberculosis complex (43 body fluids and 65 nonliquid specimens), 63 (58.3%) were positive with the Xpert MTB/RIF assay (GX). GX sensitivity was quite low for samples from sterile locations (especially for pleural fluids: 26.9%) but high for some nonliquid samples, like abscess aspirates (76.5%). In summary, GX may be a useful tool to be considered for EPTB diagnosis.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Humans
  • Mycobacterium tuberculosis / genetics
  • Mycobacterium tuberculosis / isolation & purification*
  • Real-Time Polymerase Chain Reaction / methods*
  • Sensitivity and Specificity
  • Tuberculosis / diagnosis*
  • Tuberculosis / microbiology*