Microbiome in lower respiratory diseases is not sufficiently known yet. The objective of this study is to investigate microbiome in patients who present with hemoptysis, and those with pulmonary tuberculosis, non-tuberculous mycobacterial pulmonary disease (NTM-PD), and lung cancer, analyzing respiratory specimen acquired by bronchoscopic approach.

Subjects who were going to undergo bronchoscopy for hemoptysis or suspected lower respiratory diseases including endobronchial tuberculosis (Tb), NTM-PD, or endobronchial lung cancer (LC) were enrolled after informed consents.

Subjects who were supposed to receive bronchoscopy to rule out endobronchial lesions were also enrolled as control group (ctrl) after informed consents. In those control group, endobronchial tuberculosis, malignancy or other certain respiratory diseases was not clearly suspected.

Before acquiring respiratory specimens, bronchoscopic channels were washed to acquire negative control in all cases of groups.

In Tb group and LC group, specimens of normal bronchial mucosa near suspicious endobronchial lesion were obtained with protected brush (PB), then specimens of abnormal bronchial mucosa in suspicious endobronchial lesion with PB. After acquiring respiratory specimens of PB, bronchial washing was done in suspicious endobronchial lesion.

In NTM-PD group, specimens of bronchial mucosa in bronchus of suspicious NTM-PD with PB. After acquiring respiratory specimens of PB, bronchial washing was done in bronchus of suspicious NTM-PD.

In hemoptysis group, bronchial washing was done in bronchus of ongoing bleeding.

In control group, specimens of bronchial mucosa in predetermined random bronchus (not bronchus with suspicious endobronchial lesion) with PB. After acquiring respiratory specimens of PB, bronchial washing was done in the same bronchus.

Microbiome in lower respiratory species was analyzed using 16S rRNA sequencing.

Inclusion Criteria:

• Patients who underwent bronchoscopy for hemoptysis, OR
• Patients who underwent bronchoscopy for suspicious endobronchial pulmonary tuberculosis observed on chest computed tomography, OR
• Patients who underwent bronchoscopy for suspicious non-tuberculous mycobacterial pulmonary disease (NTM-PD) observed on chest computed tomography, OR
• Patients who underwent bronchoscopy for suspicious endobronchial lung cancer observed on chest computed tomography, OR
• Patients who underwent bronchoscopy to rule out endobronchial lesion which did not seem to be typical for any criteria of pulmonary diseases including tuberculosis, NTM-PD or lung cancer on chest computed tomography

Exclusion Criteria:

• Other malignancy, infection or serious diseases of neural, cardiovascular, renal, hepatobiliary, gastrointestinal, hemotologic or respiratory system
• Use of any antibiotic within a month
• Vulnerable volunteer
• Subject's rejection

1. HM group

   • Patients who underwent bronchoscopy for hemoptysis

2. Tb group

   • Patients who underwent bronchoscopy for suspicious endobronchial pulmonary tuberculosis

3. NTM-PD group

   • Patients who underwent bronchoscopy for suspicious non-tuberculous mycobacterial pulmonary disease (NTM-PD)

4. LC group

   • Patients who underwent bronchoscopy for suspicious endobronchial lung cancer

5. Control group

   • Patients who underwent bronchoscopy to rule out endobronchial lesion which did not seem to be typical for any criteria of pulmonary diseases including tuberculosis, NTM-PD or lung cancer

Technically, results of 16S rRNA sequencing can hardly be shared. Study protocol, SAP, ICF, CSR were written in Korean, so they can not be shared either.