​The California Department of Public Health’s Microbial Diseases Laboratory serves as the National PHL Drug Susceptibility (DST) Reference Center for Mycobacterium tuberculosis. The Reference Center provides quality-assured drug susceptibility testing for eligible US public health laboratories with low volumes of testing and serves as an extension of CDC’s Division of TB Elimination Laboratory Branch providing services that are harmonized with and complementary to those available at CDC. 

Enrollment Criteria

Enrollment is restricted to public health laboratories performing TB DST on fewer than 50 isolates per year. Participation in the reference center is voluntary. CDC’s testing services remain available to all US TB Programs. Jurisdictions that are not eligible to enroll may still submit specimens and/or isolates to CDC for the Molecular Detection of Drug Resistance (MDDR) or second-line DST.

Testing Services ​

The National PHL DST Reference Center for Mycobacterium tuberculosis  will provide the following services at no cost to eligible submitting PHLs:

  • First-Line DST using MGIT with a panel of rifampin, isoniazid, pyrazinamide and ethambutol.
  • Second-Line DST using MGIT with a panel of ethionomide, capreomycin, amikacin, moxifloxacin, kanamycin (NEW) and rifabutin (NEW)
  • Molecular detection of drug resistance will be performed by pyrosequencing on specimen sediments and isolates from patients that meet pre-determined criteria for suspicion of drug resistance.

Resources for Submitting Laboratories

Submission and Shipping Instructions
Pre-submission Approval Form for Pyrosequencing
Requisition Form
Flowchart of Referral and Testing Algorithms

Reporting Language​

Additional Information​

Updates to TB DST Service​ (July 31, 2018)​​
Dear Colleague Letter (January 16, 2015)
Informational Webinar (February 19, 2015)


Please direct questions to Anne Gaynor at anne.gaynor@aphl.org​.