Low Occurrence of Tuberculosis Drug Resistance among Pulmonary Tuberculosis Patients from an Urban Setting, with a Long-Running DOTS Program in Zambia

Table 1

Phenotypic drug resistance patterns to first-line and second-line antituberculosis drugs in 193 M. tuberculosis isolates from treated and previously treated subjects.

Resistance pattern	New cases $n$ (%)	Previously treated cases $n$ (%)	Missing information $n$ (%)	Total $n$ (%)
Total	156 (80.8)	31 (16.1)	6 (3.1)	193 (100)
Pan-susceptible	144 (92.3)	26 (83.9)	6 (100)	176 (91.2)
Any resistance	12 (7.7)	5 (16.1)	0	17 (8.8)
INH	8 (5.1)	3 (9.7)	0	11 (5.7)
RMP	2 (1.3)	3 (9.7)	0	5 (2.6)
SM	3 (1.9)	3 (9.7)	0	6 (3.1)
EMB	0	1 (3.2)	0	1 (0.5)
Mono-resistance
INH	7 (4.5)	1 (3.2)	0	8 (4.1)
RMP	2 (1.3)	1 (3.2)	0	3 (1.6)
SM	2 (1.3)	0	0	2 (1.0)
EMB	0	0	0	0
Polyresistance
MDR (INH+RMP+SM+EMB)	0	1 (3.2)	0	1 (0.5)
Non-MDR
INH+SM	1 (0.6)	1 (3.2)	0	2 (1.0)
RMP+SM	0	1 (3.2)	0	1 (0.5)
OFLO	0	0	0	0
KAN	0	0	0	0

INH: isoniazid; RMP: rifampicin; SM: streptomycin; EMB: ethambutol; Oflo: ofloxacin; Kan: kanamycin, MDR, multidrug resistance.