Table 1.

Sensitivity of tests of different specimens in children with TB disease (confirmed TB and unconfirmed TB)

Test and Specimen Type			One Sample				Up to Two Samples
	Positive	N*	Sensitivity		Positive	N**	Sensitivity
Xpert			%	(95% CI)			%	(95% CI)
Gastric aspirate	14	94	14.9	(9.1 – 23.5)	16	94	17.0	(10.8 – 25.9)
String	9	93	9.7	(5.2 – 17.4)	11	93	11.8	(6.7 – 19.9)
Induced sputum	11	91	12.1	(6.9 – 20.4)	14	91	15.4	(9.4 - 24.2)
NPA	14	96	14.6	(8.9 – 23.0)	17	96	17.7	(11.4 – 26.5)
Stool	13	90	14.4	(8.6 – 23.2)	13	91	14.3	(8.5 - 22.9)
Urine	4	89	4.5	(1.8 - 11.0)	4	89	4.5	(1.8 - 11.0)
FNAB	2	5	40.0	(11.8 – 76.9)	2	5	40.0	(11.8 – 76.9)
Liquid culture (MGIT)
Gastric aspirate	21	88	23.9	(16.2 – 33.7)	22	93	23.7	(16.2 - 33.2)
String	10	87	11.5	(6.4 – 19.9)	12	91	13.2	(7.7 - 21.6)
Induced sputum	12	86	14.0	(8.2 – 22.8)	19	91	20.9	(13.8 - 30.3)
NPA	21	83	25.3	(17.2 – 35.6)	22	93	23.7	(16.2 - 33.2)
Stool	7	77	9.1	(4.5 – 17.6)	7	84	8.3	(4.1 - 16.2)
Urine	2	78	2.6	(0.7 – 8.9)	2	83	2.4	(0.7 – 8.4)
Blood	1	30	3.3	(0.6 – 16.7)	N/A		N/A
FNAB	3	5	60.0	(23.1 – 88.2)	N/A		N/A
Smear microscopy for AFB
Gastric aspirate	5	94	5.3	(2.3 – 11.9)	6	94	6.4	(3.0 - 13.2)
String	2	93	2.2	(0.6 – 7.5)	3	93	3.2	(1.1 - 9.1)
Induced sputum	4	91	4.4	(1.7 – 10.8)	4	91	4.4	(1.7 - 10.8)
NPA	6	96	6.3	(2.9 - 13.0)	6	96	6.3	(2.9 - 13.0)
Stool	4	90	4.4	(1.7 – 10.9)	4	90	4.4	(1.7 - 10.9)
Urine	1	90	1.1	(0.2 – 6.0)	1	90	1.1	(0.2 - 6.0)

^*Number of children with valid results for test performed on first specimen collected.

^**Number of children with valid results for first or second specimen collected

Xpert invalid results (error or indeterminate) and MGIT results showing contamination or nontuberculous mycobacteria were excluded.

AFB = acid fast bacteria, MGIT = mycobacterial growth indicator tube

FNAB = fine needle aspirate biopsy; NPA = nasopharyngeal aspirate

Respiratory specimens were collected overnight in the order NPA, IS, GA, string test.