A blind study of the polymerase chain reaction for the detection of Mycobacterium tuberculosis DNA. Azay Mycobacteria Study Group

Tuber Lung Dis. 1996 Aug;77(4):358-62. doi: 10.1016/s0962-8479(96)90102-1.


Setting: Nine French laboratories routinely involved in mycobacterial work.

Objective: To assess the detection of Mycobacterium tuberculosis in experimental samples by polymerase chain reaction (PCR) using the insertion sequence IS6110 as a target for deoxyribonucleic acid (DNA) amplification.

Design: Nine laboratories participated in a blind study of the detection of M. tuberculosis by PCR in 20 coded samples containing either a definite number of M. tuberculosis complex (positive samples) or environmental mycobacteria (four samples) or no mycobacteria (five samples).

Results: Five laboratories reported false-positive PCR results, with an average rate of 7%. All laboratories except one reported positive PCR results for samples containing 10(5) cfu/ml or more. M. tuberculosis DNA was detected in two thirds of samples containing 10(4) and 10(3) cfu/ml, and in one third of the samples containing 10(2) cfu/ml.

Conclusion: The results of the study suggest that PCR using IS6110 as a target for DNA amplication is neither very sensitive nor really specific for the detection of M. tuberculosis.

Publication types

  • Multicenter Study

MeSH terms

  • DNA, Bacterial / analysis*
  • False Positive Reactions
  • Humans
  • Mycobacterium / chemistry
  • Mycobacterium tuberculosis / chemistry*
  • Polymerase Chain Reaction*
  • Sensitivity and Specificity
  • Single-Blind Method
  • Sputum / microbiology


  • DNA, Bacterial