Effect of Mixed Infections with Mycobacterium tuberculosis and Nontuberculous Mycobacteria on Diagnosis of Multidrug-Resistant Tuberculosis: A Retrospective Multicentre Study in China

Figures & data

Figure 1 Distribution map of MDR-TB isolates included in this study. The number following the site number represents the number of isolates obtained from that site.

Figure 2 MeltPro Myco assay melting peaks revealing mixed infections. (A) MTB alone; (B) mixed infection by mixed infection by M. tuberculosis and M. intracellulare; (C) mixed infection by mixed infection by M. tuberculosis and M. avium; (D) mixed infection by mixed infection by M. tuberculosis and M. abscessus; IPC, internal positive control.

Figure 3 Distribution of NTM species identified in mixed infection cases.

Table 1 Demographic and Clinical Characteristics Associated with Mixed Infection of MTB and NTM

Characteristics	All	TB	NTM-TB	Crude OR
	N (%)	n (%)	n (%)	OR (95% CI)
All	837 (100)	815 (100)	22 (100)	-
Demographic characteristics
Gender
Men	627 (74.9)	613 (75.2)	14 (63.6)	Ref.
Women	210 (25.1)	202 (24.8)	8 (36.4)	0.58 (0.24, 1.40)
Ethnicity
Han	819 (97.8)	797 (97.8)	22 (100.0)	Ref.
Other	18 (2.2)	18 (2.2)	0 (0.0)	0.00 (0.00, 0.00)
Age group, years
<25	116 (13.9)	112 (13.7)	4 (18.2)	Ref.
25–39	163 (19.5)	160 (19.6)	3 (13.6)	0.53 (0.12, 2.39)
40–59	285 (34.1)	276(33.9)	9 (40.9)	0.91 (0.28, 3.03)
4.00	273 (32.6)	267(32.8)	6 (27.3)	0.63 (0.17, 2.27)
Previous TB
No	546 (65.2)	538 (66.0)	8 (36.4)	Ref.
Yes	291 (34.8)	277 (34.0)	14 (63.6)	3.40 (1.41, 8.20)
Complications
Bronchiectasia
No	752 (89.8)	735 (90.2)	17 (77.3)	Ref.
Yes	85 (10.2)	80 (9.8)	5 (22.7)	2.70 (0.97, 7.52)
Asthma
No	829 (99.0)	807 (99.0)	22 (100.0)	Ref.
Yes	8 (1.0)	8 (1.0)	0 (0.0)	0.00 (0.00, 0.00)
Diabetes
No	626 (74.8)	607 (74.5)	19 (86.4)	Ref.
Yes	211 (25.2)	208 (25.5)	3 (13.6)	0.46 (0.14, 1.57)
Hepatitis
No	732 (87.5)	711 (87.2)	21 (95.5)	Ref.
Yes	105 (12.5)	104 (12.8)	1 (4.5)	0.33 (0.04, 2.45)
COPD
No	803 (95.9)	782 (96.0)	21 (95.5)	Ref.
Yes	34 (4.1)	33 (4.0)	1 (4.5)	1.13 (0.15, 8.65)
HIV
No	833 (99.5)	811 (99.5)	22 (100.0)	Ref.
Yes	4 (0.5)	4 (0.5)	0 (0.0)	0.00 (0.00, 0.00)
Tumour
No	797 (95.2)	776 (95.2)	21 (95.5)	Ref.
Yes	40 (4.8)	39 (4.8)	1 (4.5)	0.95 (0.12, 7.23)
Autoimmunity disease
No	823 (98.3)	801 (98.3)	22 (100.0)	Ref.
Yes	14 (1.7)	14 (1.7)	0 (0.0)	0.00 (0.00, 0.00)
Chronic nephrosis
No	811 (96.9)	790 (96.9)	21 (95.5)	Ref.
Yes	26 (3.1)	25 (3.1)	1 (4.5)	1.51 (0.20, 11.63)
Clinical symptoms
Cough
No	93 (11.1)	90 (11.0)	3 (13.6)	Ref.
Yes	744 (88.9)	725 (89.0)	19 (86.4)	0.79 (0.23, 2.71)
Hemoptysis
No	636 (76.0)	618 (75.8)	18 (81.8)	Ref.
Yes	201 (24.0)	197 (24.2)	4 (18.2)	0.70 (0.23, 2.08)
Fever
No	571 (68.2)	554 (68.0)	17 (77.3)	Ref.
Yes	266 (31.8)	261 (32.0)	5 (22.7)	1.60 (0.58, 4.39)
Chest pain
No	763 (91.2)	743 (91.2)	20 (90.9)	Ref.
Yes	74 (8.8)	72 (8.8)	2 (9.1)	1.03 (0.24, 4.50)
Weight loss
No	583 (69.7)	564 (69.2)	19 (86.4)	Ref.
Yes	254 (30.3)	251 (30.8)	3 (13.6)	0.36 (0.10, 1.21)

Abbreviations: MTB, Mycobacterium tuberculosis; NTM, nontuberculous mycobacteria; CI, confidential interval; OR, odds ratio; COPD, chronic obstructive pulmonary disease; HIV, human immunodeficiency virus.