Table 4. MTBC species identification by multiplex MTBC-RD qPCR on extrapulmonary specimens in EPTB patients according to the reference standard*.
| Clinical specimens | MTBC species identification by multiplex MTBC-RD qPCR | |||||
|---|---|---|---|---|---|---|
| M. bovis, n = 121 (77.1%) | M. tuberculosis, n = 34 (21.6%) | M. bovis BCG, n = 2 (1.3%) | ||||
| Culture pos ± AFB | Culture neg CRS** pos | Culture pos ±AFB | Culture neg CRS pos | Culture pos ±AFB | Culture neg CRS pos | |
| Lymph nodesa (n = 138) | 73 | 38 | 15 | 12 | 0 | 0 |
| Pus and abscess (n = 8) | 0 | 2 | 4 | 0 | 2* | 0 |
| Body fluidb(n = 7) | 1 | 5 | 0 | 1 | 0 | 0 |
| Tissuec (n = 3) | 2 | 0 | 1 | 0 | 0 | 0 |
| Bone scrapings (n = 1) | 0 | 0 | 1 | 0 | 0 | 0 |
| Total (n = 157) | 76 (48.4%) | 45 (28.7%) | 21 (13.4%) | 13 (8.3%) | 2d (1.3%) | 0 |
MTBC: Mycobacterium tuberculosis complex
*reference standard for EPTB is defined as positive culture and/or at least two positive CRS** criteria
**CRS: Composite reference standard: (i) TB clinical symptoms, (ii) histology/cytology findings, (iii) radiological tests, (iv) therapeutic response to anti-TB treatment (ATT); AFB: Acid Fast Bacilli; pos: positive, neg: negative
a: Lymph nodes included biopsies (n = 30) and fine needle aspiration (n = 114).
b: Body fluid included CSF (n = 8) and pleural fluid (n = 1).
c: Specimen source comprised muscle, bronche, pleural and synovial tissue.
d: Patients post BCG vaccine.