Identification of Nontuberculous Mycobacteria in Patients with Pulmonary Diseases in Gyeongnam, Korea, Using Multiplex PCR and Multigene Sequence-Based Analysis

Figure 2

Representative results of mPCR using clinical isolates and detection of coinfection. A total of 320 clinical isolates were tested for the identification of mycobacterial species using the two-step mPCR method. (a) Results of the first and second mPCR using clinical isolates. The clinical isolates were analyzed using the first mPCR with M. intracellulare (Lanes 1–8, 10, and 12) and M. avium subsp. avium (Lane 11). The strain with only 16sRNA (484 bps, Lane 9) bands was later identified through the secondary mPCR or multigene sequence analysis. In particular, Lane 11, with the IS901 (753 bps), 16sRNA (484 bps), IS1311 (282 bps), and DT1 (106 bps) bands, was suspected as a M. avium subsp. avium or M. avium subsp. avium and M. intracellulare coinfection (the first mPCR, left panel). The clinical isolates were identified as M. abscessus (Lane 1), M. massiliense (Lane 2), and M. kansasii (Lane 3) (second mPCR, right panel). (b) Confirmation of coinfection results: M. avium subsp. avium (Lanes 5–6) and M. intracellulare (Lanes 7–8) were single-isolated and identified from a suspected coinfection sample in Lane 11 of panel A Lane M, DNA ladder; Lane 2, M. avium subsp. hominissuis 104; Lane 3, M. avium subsp. avium KBN12P06234; Lane 4, negative control.

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