Advanced Diagnostic Laboratories

Menu of Individual Drug Testing for Acid Fast Bacilli

Test Code

NTM3, NTM5 and MTB6

Description

The Mycobacteriology Laboratory can perform a customized selection of phenotypic antibiotic susceptibility testing for mycobacteria and partially acid fast organisms. The client must select the drugs to be tested (Note: for the routine panel of drugs, use APPRO instead of selecting individual drugs).

Individual drug testing is generally ordered when newer drugs are needed that are not part of the routine panel, or a specific selection of drugs is desired. Table 1 contains all testable drugs that may be selected for various types of organisms.

Table 1. Full menu of antibiotic susceptibility testing that may be individually ordered for various mycobacteria and acid fast organisms

Slowly growing mycobacteria (Test code: NTM3)	Rapidly growing mycobacteria (Test code: NTM5)	Mycobacterium tuberculosis (Test code: MTB6)	*M. haemophilum* (Test code: NTM3)
Amikacin Ciprofloxacin Clofazimine Clarithromycin Doxycycline Ethambutol Linezolid Minocycline Moxifloxacin Rifabutin Rifampin Rifampin/Ethambutol Synergy Streptomycin Trimethoprim-sulfamethoxazole	Amikacin Augmentin Azithromycin Cefepime Cefotaxime Cefoxitin Ceftriaxone Ciprofloxacin Clarithromycin Clofazimine Clofazimine-Amikacin Synergy Doxycycline Gentamicin Imipenem Kanamycin Linezolid Minocycline Omadacycline Moxifloxacin Tigecycline Tobramycin Trimethoprim-sulfamethoxazole	Amikacin Azithromycin Capreomycin Ciprofloxacin Clofazimine Clarithromycin Cycloserine Ethambutol Ethionamide Isoniazid Kanamycin Linezolid Levofloxacin Moxifloxacin Ofloxacin p-Aminosalicyclic acid Pyrazinamide Pyrazinamide (MIC) Rifabutin Rifampin Streptomycin	Clofazimine Linezolid

Table 1. Drug abbreviations (used on the requisition)

Abbreviation	Drug	Abbreviation cont'd	Drug cont'd
AMK	Amikacin	INH	Isoniazid
AUG	Augmentin	IPM	Imipenem
AXO	Ceftriaxone	KAN	Kanamycin
AZM	Azithromycin	LZD	Linezolid
CIP	Ciprofloxacin	MIN	Minocycline
CLO	Clofazimine	MXF	Moxifloxacin
CLO/AMK	Clofazimine & Amikacin synergy	OFX	Ofloxacin
CLR	Clarithromycin	OMC	Omadacycline
CAP	Capreomycin	PAS	p-Aminosalicyclic acid
CS	Cycloserine	PZA	Pyrazinamide
DOX	Doxycycline	RFB	Rifabutin
EMB	Ethambutol	RIF	Rifampin
ETH	Ethionamide	RIF/EMB	Rifampin & Ethambutol synergy
FEP	Cefepime	STR	Streptomycin
FOT	Cefotaxime	TGC	Tigecycline
FOX	Cefoxitin	TMP/SXT	Trimethoprim/sulfamethoxazole
GEN	Gentamicin	TOB	Tobramycin

Collect

An identified isolate is required for testing (does not necessarily apply to veterinary rapidly growing isolates).

This test can be ordered on a clinical specimen that has been sent to our laboratory for isolation and identification of mycobacteria. See specimen requirements for culture of mycobacteria from a clinical specimen (AFB1, AFB3 or AFB7)
This test can also be ordered on organisms identified elsewhere. Pure mycobacterial isolates should be sent in solid media such as a Middlebrook slant (7H10 or 7H11), Lowenstein-Jensen (LJ) slant, or in broth (7H9, MGIT, MP BACT/Alert, VersaTrek).
Specimen Volume: Laboratory must receive visible growth of an isolate on solid media or an isolate in broth media (≥ 3 mL).

Unacceptable Conditions

Cultures received with incomplete identifiers.
Mixed cultures; Note that prior to rejection, attempts will be made to isolate organisms. A re-isolation charge will be applied in these cases.
Cultures containing mold.
Solid media with insufficient growth.
Cultures submitted on agar plates.
Liquid media with < 2 mL.
Leaking specimens.

Storage Transport Temp

Transport or mail isolates at ambient temperature. For nontuberculous mycobacteria (NTM), follow IATA/ DOT category B and for M. tuberculosis complex isolates, follow IATA/DOT category A requirements for shipping biological materials.

Stability

Isolate at ambient temperature

Performed

Typically all days

Methodology

Test code	Type of organism	Drugs available	Method
NTM3	Slowly growing mycobacteria	AMK, CIP, CLO, CLR, DOX, EMB, LZD, MIN, MXF, RIF, RFB, STR, TMB/SXT	Broth microdilution
		RIF/EMB synergy	Broth microdilution
		CLO, LZD	Agar proportion
NTM5	Rapidly growing mycobacteria	AMK, AUG, AXO, AZI, CIP, CLO, CLO/AMK Synergy, CLR, DOX, FEP, FOT, FOX, GEN, IMP, KAN, LZD, MIN, MXF, TGC, TOB, TMP/SXT	Broth microdilution
MTB6	Mycobacterium tuberculosis	INH, RIF, EMB, ETH, STR, CAP, KAN, AMK, CS, PAS	Agar proportion
		INH, RIF, ETH, PYR	Broth proportion
		AMK, AZI, CAP, CIP, CLA, EMB, ETH, INH, KAN, LFX, LZD, MXF, OFX, PYR, RIF, RFB, STR	Broth macrodilution

Turnaround Time

MIC's for M. tuberculosis complex and other slowly growing mycobacteria are reported 4 to 6 weeks after a pure culture is achieved.
MIC's for rapidly growing mycobacteria and aerobic actinomycetes are reported 2 to 3 weeks after a pure culture is achieved.

Department

Infectious Disease Laboratory, Mycobacteriology

Study Offerings

CAP/CLIA

Related Tests

NTM13, AFB6, MTB1, MTB2, NTM4, NTM6, NTM15

CPT Code

Test code	Type of organism	Drugs available	Method	Billing Code	CPT code
NTM3	Slowly growing mycobacteria	AMK, CIP, CLO, CLR, DOX, EMB, LZD, MIN, MXF, RIF, RFB, STR, TMB/SXT	Broth microdilution	MICSD	87186
		RIF/EMB synergy	Broth microdilution	NTMP9	87186
		CS, CLO, LZD	Agar proportion	APSD	87181
NTM5	Rapidly growing mycobacteria	AMK, AUG, AXO, AZI, CIP, CLO, CLO/AMK Synergy, CLR, DOX, FEP, FOT, FOX, GEN, IMP, KAN, LZD, MIN, MXF, TGC, TOB, TMP/SXT	Broth microdilution	NTMP6 or NTMPV (for veterinary)	87186
MTB6	Mycobacterium tuberculosis	INH, RIF, EMB, ETH, STR, CAP, KAN, AMK, CS, PAS	Agar proportion	MTBP1	87190
		INH, RIF, ETH, PYR	Broth macrodilution	MTPB2	87188
		AMK, AZI, CAP, CIP, CLA, EMB, ETH, INH, KAN, LFX, LZD, MXF, OFX, PYR, RIF, RFB, STR	Broth macrodilution	MTBP3	87188