Additional Usefulness of Bronchoscopy in Patients with Initial Microbiologically Negative Pulmonary Tuberculosis: A Retrospective Analysis of a Korean Nationwide Prospective Cohort Study

Figures & data

Figure 1 Flowchart of the analysis. *Initial sputum study: smear, PCR, and culture were performed.

Abbreviations: PCR, polymerase chain reaction; TB, tuberculosis.

Table 1 Baseline Characteristics of Patients with Microbiologically Negative (Based on Initial Sputum PCR and Culture Results) Pulmonary TB Who Underwent Bronchoscopy According to Microbiological Confirmation After Bronchoscopy

Variables	Bronchial Washing PCR (+) or Culture (+) n=157	Bronchial Washing PCR (-) and Culture (-) n=162	p
Age	56.9±20.8	56.1±17.3	0.72
≥65 years	73 (46.5)	50 (30.9)	0.004
Sex
Male	65 (41.4)	92 (58.6)	0.047
BMI	21.3±3.2	22.6±3.5	0.001
<18.5	37 (23.6)	14 (8.7)	<0.001
Occupation	45 (28.7)	55 (34.4)	0.274
Smoking
Never	99 (63.1)	89 (54.9)	0.285
Past	30 (19.4)	34 (21.0)
Current	28 (17.8)	39 (24.1)
Past TB
New	122 (77.7)	130 (80.2)	0.529
Recurrent	29 (18.5)	29 (17.9)
Comorbidity	79 (50.3)	92 (56.8)	0.247
DM	32 (20.4)	31 (19.1)	0.78
Chronic lung disease	11 (6.8)	6 (3.8)	0.238
Chronic heart disease	3 (1.9)	6 (3.7)	0.334
Chronic liver disease	1 (0.6)	5 (3.1)	0.107
Chronic kidney disease	5 (3.2)	9 (5.6)	0.301
Neuropsychiatric disease	9 (5.7)	8 (4.9)	0.752
Malignancy	16 (10.2)	18 (11.1)	0.79
Symptoms	95 (60.5)	88 (54.3)	0.264
Cough, sputum	48 (30.6)	51 (31.5)	0.861
Dyspnea	20 (12.7)	29 (17.9)	0.201
Hemoptysis	10 (6.4)	7 (4.3)	0.415
Fever	14 (8.9)	20 (12.3)	0.321
Radiographic result
Presence of cavity	18 (11.5)	16 (9.9)	0.645
Bilateral	39 (24.8)	34 (21.0)	0.092

Abbreviations: BMI, body mass index; DM, diabetes mellitus; PCR, polymerase chain reaction.

Table 2 Predictors of Further Microbiological Confirmation After Bronchoscopy in Patients with Microbiologically Negative (Based on Initial Sputum PCR & Culture Results) Pulmonary TB Who Underwent Bronchoscopy

Variables	Univariate		Multivariate
	OR (95% CI)	p	OR (95% CI)	p
Age
≥65 years	1.947 (1.232–3.077)	0.004	1.754 (1.093–2.816)	0.02
Sex
Male	0.614 (0.387–0.974)	0.038	0.609 (0.378–0.982)	0.042
BMI
<18.5	3.237 (1.72–6.267)	<0.001	3.007 (1.534–5.894)	0.001
Smoking		0.287
Never	Ref
Past	0.793 (0.449–1.400)		–
Current	0.645 (0.367–1.134)		–
Past TB
New	Ref
Recurrent	1.066 (0.602–1.886)	0.827	–
Comorbidity
DM	1.082 (0.623–1.878)	0.78	–
Chronic lung disease	0.545 (0.197–1.513)	0.244	–
Malignancy	0.908 (0.445–1.851)	0.79	–
Symptoms
Cough, sputum	1.043 (0.649–1.677)	0.861	–
Dyspnea	1.494 (0.805–2.770)	0.203	–
Hemoptysis	1.439 (0.699–2.960)	0.323	–
Fever	1.431 (0.704–2.906)	0.322	–
Radiographic result
Presence of cavity	1.182 (0.580–2.411)	0.645	–
Bilateral	1.451 (0.843–2.496)	0.179	–

Abbreviations: BMI, body mass index; DM, diabetes mellitus; OR, odds ratio; CI, confidence interval.

Table 3 Additional Resistance Detection After Bronchoscopy

No.	Sex	Age	Drug Susceptibility Test Result (Resistance Pattern)
1	F	31	Isoniazid, rifampin, streptomycin
2	M	32	Isoniazid, streptomycin
3	F	68	Isoniazid, rifampin, ethambutol, protionamide
4	F	41	Isoniazid, pyrazinamide
5	M	79	Isoniazid, streptomycin
6	M	70	Isoniazid
7	F	31	Isoniazid
8	M	36	Rifampin
9	M	24	Isoniazid, rifampin, ethambutol, quinolone
10	F	78	Isoniazid
11	F	68	Streptomycin

Abbreviations: F, female; M, male.