Epi Profile Section 4 - Case Diagnosis

Figure 3. Tuberculosis Cases by Diagnostic Method in Texas, 2019

Figure 3. Tuberculosis Cases by Diagnostic Method in Texas, 2019. Positive culture 926, positive NAA 120, clinical case 93, provider diagnosis 14, positive smear/tissue 6.

Figure 3 shows that in 2019, most of the TB cases were diagnosed by a positive culture (79.9%). The rest were diagnosed as a clinical case (10.35%), by provider diagnosis (8.02%), by a positive nucleic acid amplification (NAA) test (1.21%), and by a positive AFB smear/tissue only (0.52%). The Centers for Disease Control and Prevention (CDC) Division of TB Elimination defines a clinical case as a TB case that is not confirmed by a positive culture or NAA test but has a positive tuberculin skin test (TST) or a positive interferon gamma release assay (IGRA) for M. tuberculosis complex, signs and symptoms compatible with TB, is on treatment with two or more anti-TB medications, and completed a diagnostic evaluation. A case by provider diagnosis is when a physician diagnoses a person to have active TB, when the criteria for a laboratory confirmed or a clinical case are not met.[1]


1. Centers for Disease Control and Prevention (CDC). Report of Verified Case of Tuberculosis Instruction Manual, 2009. 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 | Public Health Follow-Up Outcomes | Reporting Requirements | References