Table 2. New sampling methods and laboratory techniques.
| Technique | Reference | Comment | Diagnostic yield |
| Sampling | |||
| Expectorated sputum | [5] | Older children | <15% |
| Induced sputum | [65, 66] | No age limitation if completed by suction at the end of the induction | Increases diagnostic yield by 20% |
| Obtaining two samples is advised | |||
| NPA | [67] | Young children | 30% if Xpert used |
| No equipment required | |||
| GLA | Three samples are advised, or carry out in association with induced sputum | 38% | |
| FNAB | [63] | Peripheral lymph node | High diagnostic yield |
| TBNA | [68] | Mediastinal lymph node through fibroscopy, trained endoscopist | 50% |
| String test | [69] | Children aged >3 years | |
| Bacteriological laboratory | |||
| Smear | [5] | Low sensitivity (15%) | |
| MGIT (gold standard) | Shortened time versus Löwenstein–Jensen | LED fluorescence facilitates interpretation | |
| MODS | Less costly than MGIT [72, 73] | Less sensitive and specific than MGIT | |
| Xpert MTB/RIF | [70, 71] | Twice as sensitive as a smear | Lower sensitivity than culture (57%) |
| Allows concomitant rifampicin resistance detection | |||
| Immediate results | Shorter time to diagnosis useful in extrapulmonary TB |
NPA: nasopharyngeal aspirates; GLA: gastric liquid aspirates; FNAB: fine-needle aspiration biopsy; TBNA: transbronchial needle aspiration; MGIT: mycobacterial growth indicator tube; MODS: microscopic observation drug susceptibility; TB: tuberculosis.