Evaluation of Roche Amplicor PCR assay for Mycobacterium tuberculosis.
The Roche Amplicor Mycobacterium tuberculosis PCR test (RMtb-PCR) was compared with mycobacterial culture, with the BACTEC 460 system and inoculation on Lowenstein-Jensen media. Results were interpreted with an adjusted "gold standard" incorporating clinical diagnosis. A total of 1,480 clinical specimens from 1,155 patients, including tissues and fluids, as well as 141 specimens which demonstrated a positive growth index on the BACTEC 460 system were assessed. The sensitivity, specificity, and positive and negative predictive values of RMtb-PCR compared with the adjusted gold standard for clinical specimens were 79, 99, 93, and 98%, respectively. In smear-positive specimens, the sensitivity of RMtb-PCR was 98% versus 53% for smear-negative specimens. When RMtb-PCR was performed two times per week, PCR results were available an average of 21 days before the culture results. For specimens demonstrating a positive growth index on the BACTEC 460 system, RMtb-PCR had a sensitivity and specificity of 98 and 100%, respectively. This study demonstrates the value of a commercial nucleic acid amplification kit for rapid diagnosis of M. tuberculosis, particularly in smear-positive specimens or BACTEC culture-positive specimens.
Wobeser
W L
WL
University of Toronto, Department of Microbiology, Toronto Hospital, Ontario, Canada.
Krajden
M
M
Conly
J
J
Simpson
H
H
Yim
B
B
D'costa
M
M
Fuksa
M
M
Hian-Cheong
C
C
Patterson
M
M
Phillips
A
A
Bannatyne
R
R
Haddad
A
A
Brunton
J L
JL
Krajden
S
S
D001431:Bacteriological Techniques / Q000706:statistics & numerical data; D003951:Diagnostic Errors; D005069:Evaluation Studies as Topic; D006801:Humans; D009161:Mycobacterium / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification; D009164:Mycobacterium Infections / Q000175:diagnosis; D009169:Mycobacterium tuberculosis / Q000235:genetics* / Q000254:growth & development / Q000302:isolation & purification*; D016133:Polymerase Chain Reaction / Q000379:methods* / Q000706:statistics & numerical data; D012680:Sensitivity and Specificity; D013045:Species Specificity; D013997:Time Factors; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis*