Definitions and Classifications (TB Status) | Elaborations |
Pulmonary TB | An infectious respiratory disease caused Mycobacterium Tuberculosis with associating respiratory and systemic systems. |
Extrapulmonary TB | TB of organs other than lungs (i.e., pleura, lymph nodes, abdomen, skin, joints, etc). Diagnosis is to be made via: - Culture-positive specimen - Histological evidence - Strong clinical evidence consistent with active ETB - Followed by full decision by a clinical to treat with a full course of anti-TB chemotherapy. |
Latent TB | Defined as infection with Mycobacterium tuberculosis, where the bacteria may be alive but dormant in the asymptomatic patient. These patients should be diagnosed with ANY of the following: - A normal or static in a period of 6 months in CXR finding. This includes healed lesions, nodular calcifications and well demarcated fibrotic lesions. - Smear/culture negative on sputum or by bronchioalveolar lavage (if collected) - Positive Mantoux test |
New smear-positive PTB | A patient who has never been on any TB treatment, taken TB treatment for less than 30 days or who has the following - Two or more initial sputum smear examinations positive for AFB - One sputum examination positive for AFB plus radiographic abnormalities consistent with active TB as determined by a clinician - One sputum specimen positive for AFB and at least one sputum specimen that is culture-positive for AFB. |
New smear-negative PTB | A patient with PTB that does not meet the above criteria for smear-positive TB. |
Previously treated | A case of PTB that has been treated, regardless of relapse, default or failure. |
Relapse | A patient who was previously classified to be “cured” or “treatment completed who is again diagnosed with culture positive or direct visualisation via microscopy with Mycobacterium tuberculosis. |
Failure | A patient who is smear positive via sputum examination at ≥ 5 months during treatment process. |
Defaulted | A patient who has interrupted treatment for two consecutive months or more |
Cured | Former smear-positive who was smear-negative in the last month of treatment and on at least one previous occasion. |
Completed treatment | A patient who has completed treatment but do not satisfy the criteria for cured or failure. |
MDR-TB | Known as Multi-drug resistant TB. Represent strains that are not responding to at least two first-line anti-TB drugs such as Isoniazid and Rifampicin. |
XDR-TB | After satisfying the definition of MDR-TB, XDR-TB cases are patients who are also resistant to fluoroquinolone and at least one of three injectable second-line drugs (capreomycin, kanamycin and amikacin) |