Abstract
Background
We evaluated BacT/ALERT 3D liquid culture system (bioMérieux, USA) and PCR-restriction fragment length polymorphism (RFLP) for recovery and direct identification of mycobacteria, and the results were compared with a conventional culture system using an egg-based solid medium.
Methods
A total of 3,037 bronchial specimens (2,309 bronchial washing fluids and 728 bronchoalveolar lavages) were collected. Decontaminated specimens were inoculated to both BacT/ALERT MP liquid media and Ogawa solid media (3%, Shinyang, Korea). Recovery rate and detection time were compared between the two systems. Liquid media from positive cultures were centrifuged and the pellets were tested for direct identification of mycobacteria by PCR-RFLP using Myco-ID (M&D Inc., Korea).
Results
A total of 518 isolates, including 215 M. tuberculosis (MTB) and 303 non-tuberculosis mycobacteria (NTM), were recovered. The liquid media detected 492 isolates (16.2%), including 195 MTB and 297 NTM), whereas the solid media detected 416 isolates (13.7%), including 187 MTB and 229 NTM (P<0.001); 102 isolates (28 MTB and 74 NTM) were recovered only by the liquid media, while 26 (20 MTB and 6 NTM) isolates were recovered only by the solid media. The mean time to detection was 18.1 days by the liquid media and 29.3 days by the solid media (P<0.001). The overall time to species identification from inoculation was 21.8 days. Direct PCR-RFLP from the liquid media identified 39.1% of MTB, 6.3% of M. avium, 19.05 of M. abscessus, and 12.6% of M. intracellulare respectively.
REFERENCES
1. Shinnick TM, Iademarco MF, Ridderhof JC. National plan for reliable tuberculosis laboratory services using a systems approach. Recommendations from CDC and the Association of Public Health Laboratories Task Force on Tuberculosis Laboratory Services. MMWR Recomm Rep. 2005; 54:1–12.
2. Griffith DE, Aksamit T, Brown-Elliott BA, Catanzaro A, Daley C, Gordin F, et al. An official ATS/IDSA statement: diagnosis, treatment, and prevention of nontuberculous mycobacterial diseases. Am J Respir Crit Care Med. 2007; 175:367–416.
3. Global tuberculosis control: surveillance, planning, financing. WHO report 2007. Geneva, World Health Organization, (WHO/HTM/TB/2007.376).
4. Hwang EJ. Evaluation of a tuberculosis control program at community health centers. J Korean Acad Public Health Nurs. 2007; 21:241–51.
5. Della-Latta P. Mycobacteriology and Antimycobacterial Susceptibility Testing. Isengerg HD, editor. Clinical Microbiology Procedures Handbook. 2nd ed.Washington, D.C.: ASM Press;2004. p. 71–8.
6. Pfyffer GE. Mycobacterium: General Characteristics, Laboratory Detection, and Staining Procedures. Murray PR, editor. Manual of Clinical Microbiology. 9th ed.Washington, D.C.: ASM Press;2007. p. 543–72.
7. WHO. New WHO Policies: Liquid culture backgroud document. http://www.who.int/tb/dots/laboratory/policy/en/index.html. [Online] (last visited on 15 July 2008).
8. Clinical and Laboratory Standards Institute. Laboratory detection and identification of mycobacteria; proposed guideline. CLSI document M48-P. Wayne, PA; CLSI,. 2007.
9. College of American Pathologists. CAP Microbiology Checklists. http://www.cap.org. [Online] (last visited on 15 July 2008).
10. Chang CL, Park TS, Kim MN, Lee NY, Lee HJ, Suh JT. Survey on changes in mycobacterial testing practicies in Korean laboratories. Korean J Cin Microbiol. 2001; 4:108–14.
11. Gil-Setas A, Torroba L, Fernandez JL, Martinez-Artola V, Olite J. Evaluation of the MB/BacT system compared with Middlebrook 7H11 and Lowenstein-Jensen media for detection and recovery of mycobacteria from clinical specimens. Clin Microbiol Infect. 2004; 10:224–8.
12. Mirovic V, Lepsanovic Z. Evaluation of the MB/BacT system for recovery of mycobacteria from clinical specimens in comparison to Lowenstein-Jensen medium. Clin Microbiol Infect. 2002; 8:709–14.
13. Abe C, Hosojima S, Fukasawa Y, Kazumi Y, Takahashi M, Hirano K, et al. Comparison of MB-Check, BACTEC, and egg-based media for recovery of mycobacteria. J Clin Microbiol. 1992; 30:878–81.
14. Alcaide F, Benitez MA, Escribà JM, Martin R. Evaluation of the BACTEC MGIT 960 and the MB/BacT systems for recovery of mycobacteria from clinical specimens and for species identification by DNA AccuProbe. J Clin Microbiol. 2000; 38:398–401.
15. Harris G, Rayner A, Blair J, Watt B. Comparison of three isolation systems for the culture of mycobacteria from respiratory and non-respiratory samples. J Clin Pathol. 2000; 53:615–8.
16. Piersimoni C, Scarparo C, Callegaro A, Tosi CP, Nista D, Bornigia S, et al. Comparison of MB/Bact alert 3D system with radiometric BACTEC system and Lowenstein-Jensen medium for recovery and identification of mycobacteria from clinical specimens: a multicenter study. J Clin Microbiol. 2001; 39:651–7.
18. Crump JA, Tanner DC, Mirrett S, McKnight CM, Reller LB. Controlled comparison of BACTEC 13A, MYCO/F LYTIC, BacT/ALERT MB, and ISOLATOR 10 systems for detection of mycobacteremia. J Clin Microbiol. 2003; 41:1987–90.
19. Koh WJ, Kwon OJ, Jeon K, Kim TS, Lee KS, Park YK, et al. Clinical significance of nontuberculous mycobacteria isolated from respiratory specimens in Korea. Chest. 2006; 129:341–8.
20. Lee JY, Choi HJ, Lee H, Joung EY, Huh JW, Oh YM, et al. Recovery rate and charascteristics of nontuberculous mycobacterial isolates in a university hospital in Korea. Tuberc Respir Dis. 2005; 58:385–91.
21. Koh WJ, Kwon OJ, Ham HS, Suh GY, Chung MP, Kim HJ, et al. Clinical significance of nontuberculous mycobacteria isolated from respiratory specimens. Korean J Med. 2003; 65:10–21.
22. Koh WJ, Kwon OJ, Lee KS. Diagnosis and treatment of nontuberculous mycobacterial pulmonary diseases: a Korean perspective. J Korean Med Sci. 2005; 20:913–25.
23. Lew WJ, Ahn DI, Yoon YJ, Cho JS, Kwon DW, Kim SJ, et al. Clinical experience on mycobacterial diseases other than tuberculosis. Tuberc Respir Dis. 1992; 39:425–32.
24. Bai GH, Park KS, Kim SJ. Clinically isolated mycobacteria other than mycobacterium tuberculosis from 1980 to 1990 in Korea. J Korean Soc Microbiol. 1993; 28:1–5.
25. Kim YS, Jo YH, Lee HJ, Suh JT, Lee YJ. Comparison of MGIT (Mycobacteria Growth Indicator Tube) with Ogawa media for recovery of mycobacteria. Korean J Cin Microbiol. 2001; 4:58–61.
26. Choi YM. Evaluation of MGIT 960 system for recovery of mycobacteria from body fluids. Korean J Cin Microbiol. 2003; 6:69–73.
27. Choi YM, Lee MH. Evaluation of BACTEC MGIT 960 system for recovery of mycobacteria. Korean J Clin Pathol. 2000; 20:56–61.
28. Lee JY, Kim JP, Shin JH, Suh SP, Ryang DW. Detection of Mycobacterium tuberculosis using BACTEC Mycobacteria Growth Indicator Tube (MGIT) 960 system-Comparision with BACTEC 460 TB system and Ogawa media. Korean J Lab Med. 2000; 20:384–91.
29. Lee KE, Park DS, Lee YJ, Cho JH. Effects on detection rate and turnaround time by changes in the mycobacterial culture and identification methos. Korean J Lab Med. 2005; 25:46–52.
Table 1.
Method | BacT/ALERT liquid media | ||||||
---|---|---|---|---|---|---|---|
Egg-based solid media | Result | MTB | NTM | Total | |||
+ | − | + | − | + | − | ||
+ − | 167 28 | 20 2,822 | 223 74 | 6 2,734 | 390 102 | 26 2,519 | |
P-value | 0.312 | <0.001 | <0.001 |