Clinical Relevance of Nontuberculous Mycobacteria Isolated from Sputum in a Gold Mining Workforce in South Africa: An Observational, Clinical Study
Table 1
Species identified using 16S sequencing, with smear status, HIV status, and CD4 counts ().
Species
Number isolated (% of group)
Number (%) smear positive
Number with mixed species4
HIV prevalence1 (%)
Median CD42 (cells/L) (range (number included))
Clinic patient group
M. avium complex
25 (26)
2 (8)
5
8/10
87 (14, 827 [5])
M. kansasii
21 (22)
6 (29)
3
5/8
85 (39, 763 [5])
M. parascrofulaceum
9 (9)
1 (11)
0
3/3
102 (66, 138 [2])
M. fortuitum
9 (9)
2 (22)
1
1/1
[0]
M. gordonae
7 (7)
0
1
1/1
195 [1]
New species
7 (7)
1 (14)
0
3/3
475 (236, 512 [3])
Other species
18 (19)
0
2
4/5
291.5 (154, 492 [4])
Total
96
12 (12.5)
12 (12.5% of 96 isolates)
25/31 (80.6)
215.5 (14, 827 [20])
Pre-IPT3 screening group
M. gordonae
53 (39)
8 (15)
5
10/12
298 (66, 396 [8])
M. kansasii
29 (21)
11 (38)
1
9/14
183.5 (69, 544 [8])
M. avium complex
13 (10)
0
3
4/5
211 (92, 534 [4])
M. parascrofulaceum
12 (9)
2 (17)
1
1/2
223 [1]
M. fortuitum
11 (8)
0
1
3/5
358 (245, 471 [2])
M. szulgai
5 (4)
0
2
2/2
132.5 (123, 142 [2])
New species
3 (2)
0
0
0/0
[0]
Other species
10 (7)
0
2
3/3
311 (252, 370 [2])
Total
136
21 (15.4)
15 (11.0% of 136 isolates)
32/43 (74.4)
245 (66, 544 [27])
Fisher’s exact test for difference in HIV prevalence by species, both groups combined, . 2Median CD4 count by species for those known to be HIV-positive, combining both groups (clinic patients and IPT screening group) and including 8 species compared using Kruskal-Wallis test, which showed no evidence for difference by species, . 3IPT: isoniazid preventive therapy. 4For specimens containing mixed NTM species on PCR sequencing, the main species is reported; minority species were not identified, but the numbers with mixed species are given here. This does not apply to those with concurrent M. tuberculosis, who were excluded from this study.
