Table 2.
Results of microbiological assays (N = 34)
| Type of sampling | Number of tested patients | Sensitivity of particular MTb detection assay | Aggregate of MTb positivity (per sample type) | ||||||
|---|---|---|---|---|---|---|---|---|---|
| n | Microscopyb | Culture | PCR | ||||||
| n | % | n | % | n | % | n | % | ||
| Sputum | 32 | 0 | 0.0% | 7 | 21.9% | 6 | 18.8% | 9 | 28.1% |
| BAL fluid | 33 | 3 | 9.1% | 8 | 24.2% | 9 | 27.3% | 12 | 36.4% |
| LN Biopsy a | 23 | 2 | 8.7% | 9 | 39.1% | 15 | 65.2% | 16 | 69.6% |
| Pleural effusion/−biopsy | 8 | 2 | 25.0% | 3 | 37.5% | 4 | 50.0% | 6 | 75.0% |
| Aggregate of MTb positivity (per type of assay) | 34 | 5 | 14.7% | 19 | 55.9% | 24 | 70.6% | 25 | 73.5% |
The aggregates in the vertical column represent the diagnostic yield obtained through the respective sample type. The aggregates in the horizontal column represent the diagnostic yield of a particular MTb detection assay across all sample types. Some samples showed positivity in more than one test. This is accounted for in the aggregate numbers. Additionally, in one patient, more than one tissue sample was able to be tested. a21 LN biopsies were obtained by EBUS-TBNA, two by regular bronchoscopy. bDetection of acid-fast bacilli with Ziehl-Neelsen staining.
Abbreviations BAL bronchoalveolar lavage, EBUS-TBNA endobronchial ultrasound-guided transbronchial needle aspiration, LN lymph node, PCR polymerase chain reaction, MTb M. tuberculosis