• DSHS TB and Hansen's Disease Branch
    Post Office Box 149347, MC 1873
    Austin, TX 78714

    Phone: 737-255-4300
    Fax: 512-989-4010

    Email the TB Program

    Email data requests to the TB Program

Epi Profile Section 8 - Drug Resistant Tuberculosis


  • Drug resistant tuberculosis (DR-TB) presents difficult challenges to TB programs in Texas because of the high cost and long duration of treatment, and limited resources available to manage such complex cases. Additionally, medications used to treat DR-TB, particularly multi-drug resistant (MDR-TB), can be toxic and difficult to tolerate; they often require in-patient treatment for some, if not all their care. In 2018, the CDC estimated the cost of treating MDR-TB was approximately $393,000 for one patient[1], when productivity loss, medications, and case management were all included. The cost for treating drug-susceptible TB was significantly less, at $49,000.[1] While DR-TB is curable, the course of treatment often negatively impacts a patient’s quality of life.
  • Individuals acquire DR-TB in the following ways:
    1. Primary resistance - Occurs in persons who are initially diagnosed with resistant organisms. This occurs in recent transmission of drug-resistant TB or reactivation of a latent drug resistant infection.
    2. Secondary resistance - Acquired drug resistance that develops during TB therapy. This occurs if therapy was not prescribed or taken correctly.
  • An average of eight MDR-TB cases per year was reported in Texas from 2015 to 2019.


Types of Drug Resistant TB

  • Isoniazid (INH) mono-resistant TB - TB that is resistant to one of the essential first-line drugs needed to treat TB, isoniazid. While therapy is available with additional first-line drugs and other oral agents, this resistance is one drug away from becoming multi-drug resistant TB, as described below.
  • Rifampin mono-resistant TB (RR) - TB that is resistant to one of the most essential first-line drugs needed to treat TB, rifampin (RIF). Medication regimens for this resistance can be more complex than for INH resistance alone. Therapy can take 18 months, compared to six to nine months for drug-susceptible TB, and is treated like MDR-TB, as described below.
  • Multidrug-resistant TB (MDR-TB) - TB that is resistant to at least two essential first-line medications used to treat TB, INH and RIF. Treatment can last from 18 months to two years and includes a more complex and potentially difficult to tolerate regimen with many drugs.
  • Pre-extensively drug-resistant TB (Pre-XDR) - TB that is resistant to both the essential first-line medications, INH and RIF, and resistant to either a fluoroquinolone or a second-line injectable anti-TB drug (kanamycin, capreomycin, or amikacin), but not both. Treatment can last 24 months or longer, and the medications used have many side effects that make it difficult to tolerate.
  • Extensively drug-resistant TB (XDR-TB) - TB that is resistant to both the essential first-line medications, INH and RIF, resistant to a fluoroquinolone, and resistant to a second-line injectable anti-TB drug (kanamycin, capreomycin, or amikacin). XDR-TB is the most difficult type of TB to treat, typically requiring six different medications with treatment lasting over 24 months.

 

Figure 5. Number of Multidrug-resistant TB and Pre-XDR Cases, Texas, 2015-2019

    Figure 5. Number of Multidrug-resistant TB and Pre-XDR Cases, Texas, 2015-2019. 2015, MDR 9, Pre-XDR 0; 2016, MDR 9, Pre-XDR 2; 2017, MDR 8, Pre-XDR 3; 2018, MDR 7, Pre-XDR 1; 2019, MDR 8, Pre-XDR 3.
*There were no XDR-TB cases reported in Texas between 2015 and 2019; 
2019 data is considered provisional data.

 

Table 10. Number of Different Types of Drug Resistant TB Cases, Texas, 2015 -2019
Drug Resistant Profile

2015

2016

2017

2018

2019

No Resistance

849

808

618

744

767

Isoniazid Mono-Resistant

26

36

19

32

38

Rifampin Mono-Resistant

0

1

0

1

0

Other Resistance*

100

66

73

77

77

MDR (but not Pre-XDR)

9

9

8

7

8

Pre-XDR

0

2

3

1

3

XDR

0

0

0

0

0

Not Performed**

343

325

396

267

266

Total Number of TB Cases

1,327

1,247

1,118

1,129

1,159

* Any drug-resistant tuberculosis, not including Isoniazid monoresistance, rifampin monoresistance, MDR, pre-XDR, and XDR.
** Represents TB cases where sputum sample was not collected for drug resistance test or test was not performed.


More information on DR-TB (PDF)

 


Notes

1. Centers for Disease Control and Prevention (CDC). The Costly Burden of Drug Resistant TB Disease in the U.S. Atlanta, GA: US Department of Health and Human Services, CDC; 2019.


Table of Contents | An Overview of Tuberculosis in Texas | Geographic Distribution of Tuberculosis in Texas | Affected Populations | Case Diagnosis | Recent Transmission | Mortality | Risk Factors Associated with Tuberculosis | Drug Resistant TB | Contact Investigation Outcomes | Reporting Requirements | References


Last updated May 26, 2021