The mycobacteriology laboratory and new diagnostic techniques
1Department of Medical Communications, Infectious Diseases, Merck & Co., Inc., Blue Bell, Pennsylvania, USA. gail_woods@merck.com
Infectious Disease Clinics of North America
|March 29, 2002
Summary
Rapid laboratory tests for mycobacterial detection and identification are crucial for tuberculosis (TB) control. Advances in nucleic acid amplification (NAA) tests offer significant potential for improving patient care and TB management.
Area of Science:
- Clinical Microbiology
- Infectious Diseases
- Public Health
Background:
- Established 1993 CDC recommendations for mycobacterial testing (AFB stains, culture, identification, susceptibility testing) and reporting times for tuberculosis (TB) control.
- Significant advancements in laboratory diagnostics have since improved mycobacterial detection, identification, and susceptibility testing capabilities and efficiency.
Purpose of the Study:
- To review and update recommendations for optimal laboratory testing methods for mycobacteria, focusing on recent technological advancements.
- To highlight the impact of new diagnostic tools, particularly nucleic acid amplification (NAA) tests, on the management of suspected TB cases.
Main Methods:
- Review of commercial nucleic acid amplification (NAA) tests for direct detection of Mycobacterium tuberculosis complex (MTBC).
- Evaluation of automated, non-radiometric systems for mycobacterial culture and identification.
- Assessment of molecular techniques for mycobacterial identification and epidemiological studies.
- Consideration of automated systems and guidelines for MTBC and nontuberculous mycobacteria (NTM) susceptibility testing.
Main Results:
- Commercial NAA tests, including the MTD assay, show great potential for patient care, approved for both smear-positive and smear-negative specimens.
- Automated culture systems are available; molecular identification techniques are primarily used in research settings.
- Molecular tests aid in understanding TB epidemiology and investigating laboratory cross-contamination.
- Automated susceptibility testing systems for MTBC are under evaluation, with one approved system available.
Conclusions:
- Nucleic acid amplification (NAA) tests represent a significant advancement in the direct detection of MTBC, improving patient management.
- Continued development and evaluation of automated and molecular technologies are essential for enhancing laboratory efficiency and accuracy in mycobacterial diagnostics.
- Updated guidelines for mycobacterial testing and susceptibility testing are crucial for effective TB control.
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