Table 2.

Measurement of antimycobacterial activity of effusion sample (eluent) (ug/mL)^†

Day	Isoniazid			Mean ± SD	Rifampicin			Mean ± SD	Isoniazid + rifampicin			Mean ± SD
	1 g				1 g				1 g + 1 g
	1*	2*	3*		1*	2*	3*		1*	2*	3*
1	19.968	9.984	9.984	13.31 ± 5.76	0.625	0.624	0.313	0.52 ± 0.18	39.936	20.001	9.984	23.31 ± 15.25
3	0.624	1.248	0.624	0.83 ± 0.36	ND	ND	ND	ND	0.624	ND	0.312	0.47 ± 0.22
7	1.284	ND	1.248	1.25 ± 0.00	ND	ND	ND	ND	0.312	0.156	0.312	0.26 ± 0.09
14	0.500	1.000	1.000	0.83 ± 0.29	ND	ND	ND	ND	0.250	0.062	0.125	0.15 ± 0.10
30	ND	0.500	0.250	0.38 ± 0.18	ND	ND	ND	ND	0.063	0.063	0.063	0.06 ± 0.00

	2 g				2 g				2 g + 2 g
1	39.936	19.968	19.968	26.62 ± 11.53	2.500	2.500	25.00	2.50 ± 0.0	39.936	79.872	79.872	66.56 ± 23.06
3	2.496	2.496	2.496	2.50 ± 0.00	0.250	0.250	0.016	0.17 ± 0.14	2.496	2.496	2.496	2.50 ± 0.00
7	2.496	2.496	2.496	2.50 ± 0.00	0.063	0.250	NC	0.16 ± 0.13	1.248	1.248	0.624	1.04 ± 0.36
14	2.000	2.000	2.000	2.00 ± 0.00	0.031	0.031	NC	0.03 ± 0.00	0.499	0.499	0.499	0.50 ± 0.00
30	ND	2.000	1.000	1.50 ± 0.71	ND	ND	ND	ND	0.500	0.250	0.125	0.29 ± 0.19

	4 g				4 g
1	79.872	79.872	39.936	66.56 ± 23.06	5.000	10.001	5.000	6.67 ± 2.89
3	4.992	4.992	2.496	4.16 ± 1.44	2.003	1.002	2.003	1.67 ± 0.58
7	4.992	4.992	4.992	4.99 ± 0.00	1.002	1.002	2.003	1.34 ± 0.58
14	4.000	8.000	7.992	6.66 ± 2.31	0.500	1.000	1.002	0.83 ± 0.29
30	4.006	2.000	8.013	4.67 ± 3.06	0.500	1.002	4.006	1.84 ± 1.90

^†Eluent was considered effective against Mycobacterium tuberculosis when the concentration was greater than 0.031 ug/mL for isoniazid or greater than 0.016 ug/mL for rifampicin; * results from individual discs; ND = not detectable.