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. 2025 Aug 25;25:647. doi: 10.1186/s12887-025-05554-3

Table 1.

Clinical case definitions, based on [12]

Clinical Case Definition
Confirmed TB

Microbiological confirmation obtained; requires Mtb to be confirmed (culture or Xpert MTB/RIF assay) from at least 1 of the following:

1) Day 1 NPA MGIT culture

2) Day 2 NPA MGIT culture

3) Day 2 GA MGIT culture

4) Day 1 NPA LJ culture

5) Day 2 NPA LJ culture

6) Day 2 GA LJ culture

7) Day 1 NPA Xpert MTB/RIF Ultra

8) Day 2 NPA Xpert MTB/RIF Ultra

9) Day 2 GA Xpert MTB/RIF Ultra

10) Stool Xpert MTB/RIF Ultra

Unconfirmed TB

Microbiological confirmation NOT obtained (i.e., NOT ‘Confirmed TB’) AND at least 2 of the following:

1. Symptoms/signs suggestive of tuberculosis (one or more of the following: persistent cough, weight loss/failure to thrive, persistent unexplained fever)

2. Chest radiograph consistent with TB

3. Close tuberculosis exposure or immunologic evidence of Mtb infection

4. Positive response to tuberculosis treatment (requires documented positive clinical response on tuberculosis treatment)

Subcategoriesa:

- With Mtb infection (Immunological evidence of Mtb infection)

- Without Mtb infection (no immunological evidence of Mtb infection)

Unlikely TB

NOT ‘Confirmed TB AND NOT ‘Unconfirmed TB’ AND

• Clinical suspicion of intrathoracic TB (i.e., compatible symptoms irrespective of duration) AND

• Both of the following:

1. At least one follow-up visit with complete clinical data

2. Chest X-ray of sufficient quality available

Subcategories:

- With Mtb infection (Immunological evidence of Mtb infection (TST or IGRA positive)

- Without Mtb infection (No immunological evidence of Mtb infection)

Asymptomatic

NOT (‘Confirmed TB’ OR ‘Unconfirmed TB’ OR ‘Unlikely TB’) AND

• No symptoms/signs suggestive of tuberculosis

Subcategories:

- With Mtb infection (Immunological evidence of Mtb infection (TST or IGRA positive)

- Without Mtb infection (No immunological evidence of Mtb infection)

Unclassifiable

NOT (‘Confirmed TB’ OR ‘Unconfirmed TB’ OR ‘Unlikely TB’ OR ‘Asymptomatic’)

AND

1. Insufficient data, defined as either:

a. No relevant follow-up visit with complete clinical data

b. No Chest X-ray of sufficient quality available

 OR

2. Determined to be unclassifiable by the Expert Panel

Mtb Mycobacterium tuberculosis; TB tuberculosis; NPA nasopharyngeal aspirate; GA gastric aspirate; MGIT Mycobacteria Growth Indicator Tube, LJ Löwenstein–Jensen; TST tuberculin skin test; IGRA interferon gamma release assay

aFor the purposes of determining immunological evidence of Mtb infection, only TST (no IGRA) is done on all participants. 

[12]