Presumptive identification of Mycobacterium tuberculosis complex based on cord formation in BACTEC MGIT 960 medium.
We considered samples received for culture of mycobacteria using BACTEC MGIT 960 system over a period of 1 year. Tubes flagged positive by MGIT were evaluated for presence of serpentine cording. The cord formation was compared with isolates identified as Mycobacterium tuberculosis complex (MTC) based on p-nitrobenzoic acid (PNB) test. Cords were found in 591 isolates of which 584 (98.8%) were confirmed as MTC. The sensitivity and specificity of cord formation were found to be 99.7% and 89.9%, respectively.
Department of Microbiology, Lala Ram Swarup Institute of Tuberculosis and Respiratory Diseases, New Delhi   110 030, India.
R
R
Singhal
J
J
Arora
M
M
Bhalla
P
P
Lal
S
S
Reza
D
D
Behera
V P
VP
Myneedu
D001431:Bacteriological Techniques / Q000379:methods*; D003470:Culture Media / Q000737:chemistry*; D006801:Humans; D008853:Microscopy / Q000379:methods; D009169:Mycobacterium tuberculosis / Q000145:classification* / Q000166:cytology / Q000254:growth & development / Q000302:isolation & purification*; D012680:Sensitivity and Specificity
D003470:Culture Media