Skip to main content
NCBI home page
Journal of Clinical Microbiology logoLink to Journal of Clinical Microbiology
. 1997 Apr;35(4):988–991. doi: 10.1128/jcm.35.4.988-991.1997

False-positive results from cultures of Mycobacterium tuberculosis due to laboratory cross-contamination confirmed by restriction fragment length polymorphism.

J Bauer 1, V O Thomsen 1, S Poulsen 1, A B Andersen 1
PMCID: PMC229718  PMID: 9157170

Abstract

During 1994, a cross-contamination problem leading to false-positive cultures of Mycobacterium tuberculosis was revealed in a mycobacteriology laboratory processing 30,000 to 35,000 samples per year. Molecular strain typing based on restriction fragment length polymorphism confirmed the contaminations. Out of 1,439 positive cultures of Mycobacterium tuberculosis, 49 samples from 48 patients were suspected to be cross-contaminated. In 37 cases, growth was observed both in BACTEC vials and on solid media, indicating that the contamination took place during the processing of the samples. The majority of the contaminated samples had been handled by the same technician.

Full Text

The Full Text of this article is available as a PDF (55.5 KB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Burki D. R., Bernasconi C., Bodmer T., Telenti A. Evaluation of the relatedness of strains of Mycobacterium avium using pulsed-field gel electrophoresis. Eur J Clin Microbiol Infect Dis. 1995 Mar;14(3):212–217. doi: 10.1007/BF02310358. [DOI] [PubMed] [Google Scholar]
  2. Das S., Chan S. L., Allen B. W., Mitchison D. A., Lowrie D. B. Application of DNA fingerprinting with IS986 to sequential mycobacterial isolates obtained from pulmonary tuberculosis patients in Hong Kong before, during and after short-course chemotherapy. Tuber Lung Dis. 1993 Feb;74(1):47–51. doi: 10.1016/0962-8479(93)90068-9. [DOI] [PubMed] [Google Scholar]
  3. Dunlap N. E., Harris R. H., Benjamin W. H., Jr, Harden J. W., Hafner D. Laboratory contamination of Mycobacterium tuberculosis cultures. Am J Respir Crit Care Med. 1995 Nov;152(5 Pt 1):1702–1704. doi: 10.1164/ajrccm.152.5.7582316. [DOI] [PubMed] [Google Scholar]
  4. Jones W. D., Jr Bacteriophage typing of Mycobacterium tuberculosis cultures from incidents of suspected laboratory cross-contamination. Tubercle. 1988 Mar;69(1):43–46. doi: 10.1016/0041-3879(88)90039-6. [DOI] [PubMed] [Google Scholar]
  5. MacGregor R. R., Clark L. W., Bass F. The significance of isolating low numbers of mycobacterium tuberculosis in culture of sputum specimens. Chest. 1975 Oct;68(4):518–523. doi: 10.1378/chest.68.4.518. [DOI] [PubMed] [Google Scholar]
  6. Maurer J. R., Desmond E. P., Lesser M. D., Jones W. D., Jr False-positive cultures of Mycobacterium tuberculosis. Chest. 1984 Sep;86(3):439–443. doi: 10.1378/chest.86.3.439. [DOI] [PubMed] [Google Scholar]
  7. Small P. M., Hopewell P. C., Singh S. P., Paz A., Parsonnet J., Ruston D. C., Schecter G. F., Daley C. L., Schoolnik G. K. The epidemiology of tuberculosis in San Francisco. A population-based study using conventional and molecular methods. N Engl J Med. 1994 Jun 16;330(24):1703–1709. doi: 10.1056/NEJM199406163302402. [DOI] [PubMed] [Google Scholar]
  8. Small P. M., McClenny N. B., Singh S. P., Schoolnik G. K., Tompkins L. S., Mickelsen P. A. Molecular strain typing of Mycobacterium tuberculosis to confirm cross-contamination in the mycobacteriology laboratory and modification of procedures to minimize occurrence of false-positive cultures. J Clin Microbiol. 1993 Jul;31(7):1677–1682. doi: 10.1128/jcm.31.7.1677-1682.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Small P. M., Shafer R. W., Hopewell P. C., Singh S. P., Murphy M. J., Desmond E., Sierra M. F., Schoolnik G. K. Exogenous reinfection with multidrug-resistant Mycobacterium tuberculosis in patients with advanced HIV infection. N Engl J Med. 1993 Apr 22;328(16):1137–1144. doi: 10.1056/NEJM199304223281601. [DOI] [PubMed] [Google Scholar]
  10. Smith W. B., Vance D. W., Jr Specimen cross-contamination by a strain of Mycobacterium tuberculosis lacking nitrate reductase activity. Diagn Microbiol Infect Dis. 1991 Nov-Dec;14(6):523–526. doi: 10.1016/0732-8893(91)90012-5. [DOI] [PubMed] [Google Scholar]
  11. Wurtz R., Demarais P., Trainor W., McAuley J., Kocka F., Mosher L., Dietrich S. Specimen contamination in mycobacteriology laboratory detected by pseudo-outbreak of multidrug-resistant tuberculosis: analysis by routine epidemiology and confirmation by molecular technique. J Clin Microbiol. 1996 Apr;34(4):1017–1019. doi: 10.1128/jcm.34.4.1017-1019.1996. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Yang Z. H., de Haas P. E., Wachmann C. H., van Soolingen D., van Embden J. D., Andersen A. B. Molecular epidemiology of tuberculosis in Denmark in 1992. J Clin Microbiol. 1995 Aug;33(8):2077–2081. doi: 10.1128/jcm.33.8.2077-2081.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Yang Z. H., de Haas P. E., van Soolingen D., van Embden J. D., Andersen A. B. Restriction fragment length polymorphism Mycobacterium tuberculosis strains isolated from Greenland during 1992: evidence of tuberculosis transmission between Greenland and Denmark. J Clin Microbiol. 1994 Dec;32(12):3018–3025. doi: 10.1128/jcm.32.12.3018-3025.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. van Embden J. D., Cave M. D., Crawford J. T., Dale J. W., Eisenach K. D., Gicquel B., Hermans P., Martin C., McAdam R., Shinnick T. M. Strain identification of Mycobacterium tuberculosis by DNA fingerprinting: recommendations for a standardized methodology. J Clin Microbiol. 1993 Feb;31(2):406–409. doi: 10.1128/jcm.31.2.406-409.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Journal of Clinical Microbiology are provided here courtesy of American Society for Microbiology (ASM)

RESOURCES