TABLE 1.
Identification of 34 Mycobacterium species, by PCR-RLB
| Species | Total no. of isolates | Identification methoda (no. of isolates) | PCR result | RLB result with probe MYCb | Species-specific probe used for RLBc (no. of isolates) | ITS sequencing result (no. of isolates) |
|---|---|---|---|---|---|---|
| M. abscessus | 12 | GC (8) | + | + | ABS (12) | NDd |
| HPLC (4) | ||||||
| M. chelonae complex | 28 | GC (28) | ND | |||
| M. abscessus | + | + | ABS (26) | ND | ||
| M. chelonae a/b | + | + | CHE1 (2) | ND | ||
| M. chelonae | 4 | HPLC (4) | + | + | CHE1 (3), CHE and FOR1 (1) | ND |
| M. chelonae a/b | Uninterpretablee (1) | |||||
| M. chelonae c | None found | ND | ||||
| MAC | 3 | GC (3) | + | + | INT (3) | ND |
| M. avium | 23 | HPLC (23) | + | + | AVI (11), INT (10), AVI and KAN1 (2) | M. intracellulare (1), uninterpretable (2) |
| M. fortuitum complex | 29 | GC (22) | + | + | FOR1 (12); FOR2 and FOR3 (1); FOR1, FOR2, and FOR3 (9) | Uninterpretable (2) |
| HPLC (7) | + | + | FOR1 (4); FOR2 and FOR3 (1); FOR1, FOR2, and FOR3 (2) | Uninterpretable (3) | ||
| M. gordonae | 28 | GC (20) | + | + | GOR (16); GOR and ABS (2); GOR and FOR1 (1); GOR and FOR1, FOR2, and FOR3 (1) | Uninterpretable (4) |
| HPLC (8) | + | + | GOR (8) | ND | ||
| M. intracellulare | 2 | HPLC (2) | + | + | AVI (1), INT (1) | M. avium (1), M. intracellulare (1) |
| M. kansasii | 3 | GC (1) | + | + | KAN1 (1) | ND |
| HPLC (2) | + | + | KAN1 (1), KAN2 (1) | ND | ||
| M. lentiflavum | 2 | HPLC (2) | + | + | LEN (2) | M. lentiflavum (2) |
| M. leprae | 3f | ND | + | + | LEP (2), MTBC and INT (1) | M. leprae (2), uninterpretable (1) |
| M. malmoense | 1 | HPLC (1) | + | + | MAL (1) | ND |
| M. nonchromogenicum | 11 | GC (11) | + | + | − (10),g FOR1 (1) | M. fortuitum a (1) |
| M. phlei a | 12 | GC (12) | + | + | PHL1 (12) | ND |
| M. phlei b | None found | |||||
| M. scrofulaceum | 15 | GC (8) | + | + | SCR (7), SCR and INT (1) | Uninterpretable (1) |
| HPLC (7) | + | + | SCR (7) | ND | ||
| M. smegmatis | 2 | HPLC (2) | + | + | SME (2) | ND |
| M. szulgai | 1 | GC (1) | + | + | SZU (1) | ND |
| M. triplex | 2 | HPLC (2) | + | + | TRI (2) | M. triplex (2) |
| M. tuberculosis complex | 39 | GC (20) | + | + | MTBC (39) | ND |
| HPLC (19) | ||||||
| M. ulcerans/M. marinum | 1 | HPLC (1) | + | + | ULC/MAR (1) | ND |
| M. xenopi | 1 | HPLC (1) | + | + | XEN (1) | ND |
| Total | 222h |
GC was performed with isolates obtained from Shenzhen Chronic Disease Hospital and Guangzhou Thoracic Hospital, China; HPLC was performed with isolates from the Mycobacterium Reference Laboratory, Centre for Infectious Diseases and Microbiology, ICPMR, Westmead, Australia.
MYC, Mycobacterium genus-specific probe; +, positive hybridization.
For the specificities of the probes on RLB, see Table 2.
ND, not done; sequencing was not performed if the HPLC or GC and PCR-RLB assay results were the same.
All cultures in which mixed species were present, as identified by the PCR-RLB assay, produced uninterpretable sequencing results.
Three clinical biopsy specimens with acid-fast bacilli on microscopy presumed to be M. leprae.
No probes specific for M. nonchromogenicum were included in the RLB.
The total includes 219 clinical isolates and three skin biopsy specimens.