GeneXpert GXMTB RIF-10, User Manual

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English
16 301-0191 Rev. C, May 2012
a
Represents results of 1 direct Xpert test, 3 smears, and 4 cultures.
The Xpert MTB/RIF Assay results on specimens from those sites where a NAAT test was
also performed are shown in Table . The NAAT test result is shown for comparison.
a
Xpert(3) = results of 3 Xpert tests, 3 smears, and 4 cultures; Xpert(1) = results of 1 direct
Xpert test, 3 smears, and 4 cultures; NAAT = ProbeTec (Azerbaijan), and AMPLICOR
(South Africa and India); NAAT “borderline” treated as negative.
South Africa-2 100%
(1/1)
[20.7%-100%] 100%
(23/23)
[85.7%-100%]
India 97.4%
(76/78)
[91.1%-99.3%] 97.1%
(33/34)
[85.1%-99.5%]
Overall 97.2%
(141/145)
[93.1%-98.9%] 98.3%
(412/419)
[96.6%-99.2%]
Table 6. Comparison of Xpert MTB/RIF Assay and Alternative NAAT Performance on Sputum Speciments
Statistic Test
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Azerbaijan South Africa-1 India Overall
Sensitivity
S+C+ Xpert(3) 100%
(76/76)
[95.2%-100%] 99.0%
(95/96)
[94.3%-99.8%] 98.8%
(160/162)
[95.6%-99.7%] 99.1%
(331/334)
[97.4%-99.8%]
Xpert(1) 97.3%
(73/75)
[90.8%-99.3%] 96.8%
(92/95)
[91.1%-98.9%] 98.8%
(159/161)
[95.6%-99.7%] 97.9%
(324/331)
[95.7%-99.2%]
NAAT 100%
(76/76)
[95.2%-100%] 93.7%
(89/95)
[86.9%-97.1%] 94.2%
(147/156)
[89.4%-96.9%] 95.4%
(312/327)
[92.3%-97.4%]
Sensitivity
S-C+ Xpert(3) 92.3%
(60/65)
[83.2%-96.7%] 90.4%
(47/52)
[79.4%-95.8%] 88.5%
(23/26)
[71.0%-96.0%] 90.9%
(130/143)
[85.0%-95.1%]
Xpert(1) 68.8%
(44/64)
[56.6%-78.8%] 86.3%
(44/51)
[74.3%-93.2%] 69.2%
(18/26)
[50.0%-83.5%] 75.2%
(106/141)
[67.2%-82.1%]
NAAT 66.2%
(43/65)
[54.0%-76.5%] 45.7%
(16/35)
[30.5%-61.8%] 72.0%
(18/25)
[52.4%-85.7%] 61.6%
(77/125)
[52.5%-70.2%]
Specificity Xpert(3) 95.8%
(69/72)
[88.5%-98.6%] 98.4%
(186/189)
[95.4%-99.5%] 97.2%
(35/36)
[85.8%-99.5%] 97.6%
(290/297)
[95.2%-99.1%]
Xpert(1) 97.2%
(69/71)
[90.3%-99.2%] 99.5%
(185/186)
[97.0%-99.9%] 100%
(35/35)
[90.1%-100%] 99.0%
(289/292)
[97.0%-99.8%]
NAAT 95.8%
(69/72)
[88.5%-98.6%] 100%
(187/187)
[98.0%-100%] 100%
(36/36)
[90.4%-100%] 99.0%
(292/295)
[97.1%-99.8%]
Table 5. Xpert MTB/RIF Assay Performance on Sputum Specimens (Continued)
Site Sensitivity in RIF Resistant Cases
Specificity in RIF Sensitive
Cases