Laboratory Information

The Division of Tuberculosis Elimination (DTBE) Laboratory Branch (LB) provides services for the following tests on mycobacterial cultures. Any local health department, licensed physician’s office, licensed laboratory or licensed health care facility may submit cultures for testing but they must be routed through either their state health department or other authorized facility.

Genotyping

State or local TB control programs

A genotyping laboratory, in Michigan  is under contract with CDC to provide genotyping services to TB programs in the United States. Three genotyping methods to identify TB strains:

• Spoligotyping
• Mycobacterial interspersed repetitive unit (MIRU) analysis
• IS6110-based restriction fragment length polymorphism (RFLP) analysis

For more information, view the Guide to the Application of Genotyping to Tuberculosis Prevention and Control.

DTBE epidemiologic investigations and surveillance activities

• The LB provides support for DTBE epidemiologic investigations and surveillance activities. TB genotyping results, when combined with epidemiologic data, help to distinguish TB patients who are involved in the same chain of recent transmission.

Drug susceptibility testing

The LB performs drug susceptibility testing for selected Mycobacterium species referred from state or other authorized health facilities. Cultures of mycobacteria are tested by the indirect proportion method with antituberculosis drugs incorporated into 7H10 agar plates.

• Molecular Detection of Drug Resistance (MDDR) CDC offers a service for the molecular detection drug resistance to rapidly identify multidrug-resistant TB. This service utilizes DNA sequencing for detection of mutations most frequently associated with rifampin and isoniazid drug resistance. Additional testing will be conducted to identify mutations associated with resistance to the most effective second-line drugs; fluroquinolones, amikacin, kanamycin, and capreomycin.
  • Molecular Detection of Drug Resistance Request Form (PDF – 24k)
  • Laboratory User Guide for U.S. Public Health Laboratories: Molecular Detection of Drug Resistance (MDDR) in Mycobacterium tuberculosis Complex by DNA Sequencing (Version 2.0) (PDF – 119K)
  • Specimen Submission Form

Additional Resources

• Report of an Expert Consultation on the Uses of Nucleic Acid Amplification Tests for the Diagnosis of Tuberculosis
• Report of Expert Consultations on Rapid Molecular Testing to Detect Drug-Resistant Tuberculosis in the United States
• Model Performance Evaluation Program (MPEP)
• Interim Laboratory Biosafety Guidance for Extensively Drug-Resistant (XDR) Mycobacterium tuberculosis strains
• Guidelines for Using the QuantiFERON®-TB Gold Test for Detecting Mycobacterium tuberculosis Infection, United States
• Tuberculosis Laboratory Aggregate Reports
  These reports contain annual workload and turnaround time data from public health laboratories supported in part by the TB Elimination Cooperative Agreement.