Mycobacterium, Rapid Grower, Susceptibility Test
For mycobacteria isolated in CTBL or in other laboratories
Isolates identified in referring labs must specify the organism’s identification and clinical source on the lab request form. For further instructions on packing, refer under IDENTIFICATION OF MYCOBACTERIA.
Susceptible, Intermediate, Resistant, according to CLSI interpretive criteria
1 - 2 weeks
Once a week
Drugs tested: Amikacin, cefoxitin, ciprofloxacin, clarithromycin*, doxycycline, imipenem**, linezolid, tobramycin***, trimethoprim-sulfamethoxazole and moxifloxacin. Tigecycline MICs are provided only upon request as there are no interpretative guidelines. *Class representative for newer macrolides e.g. azithromycin. For the detection of the erm gene which causes inducible resistance to macrolides, a preliminary result is issued if the isolate is susceptible after Day 5 of incubation, followed by a final result after Day 14. ** Tentative CLSI breakpoints. Not predictive of results for meropenem or ertapenem as the activity against rapidly growing mycobacteria is greater for imipenem than for meropenem or ertapenem. ***M. chelonae from eye cultures only.
29 Apr 2016 06:25 PM
Re-organized the wordings for the Remarks section.
15 Jan 2018 06:25 PM
Added in "To detect the erm gene which causes inducible resistance to macrolides" under remarks.
22 May 2018 06:25 PM
Amend "To detect" into "For the detection of" - in Remarks section.