Study aims to uncover hidden health differences in rare lung infections

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: \- Age: 18 years or older, able to provide informed consent. NTM-PD Group: * Participants will be adults diagnosed with confirmed NTM-PD based on the British Thoracic Society (BTS) guidelines. * The participant should not be on any antimicrobial therapy (at least two weeks before participation) and should not have previously received or be currently on antimicrobial therapy for NTM-PD. \* BTS guidelines: * Clinical (both required): * Pulmonary symptoms, nodular or cavitary opacities on chest radiograph, or a high-resolution CT scan that shows multifocal bronchiectasis with multiple small nodules. * Appropriate exclusion of other diagnoses. * Microbiological: * A minimum of two positive expectorated sputum culture results of the same NTM species from samples collected on separate days within 12 months before recruitment. OR * Positive culture results from at least one bronchial wash or lavage. OR * Transbronchial or other lung biopsy with mycobacterial histopathological features (granulomatous inflammation or AFB) and positive culture for NTM or biopsy showing mycobacterial histopathological features (granulomatous inflammation or AFB) and one or more sputum or bronchial washings that are culture-positive for NTM. Bronchiectasis Group: * Diagnosed with bronchiectasis, as confirmed in medical records based on clinical assessment, and radiological findings. * Never had a history of positive culture result for NTM pulmonary infection. * The latest NTM-negative result must be within the past 12 months from the study's start date or no earlier than 2024. Exclusion Criteria: \- Age: Under 18 years of age, or unable to provide informed consent. NTM-PD Group: * No confirmation of NTM-PD diagnosis. * Diagnosed with a reinfection of NTM-PD. * Started antimicrobial therapy for NTM-PD. Bronchiectasis Group: * No diagnosis of bronchiectasis or diagnosis of bronchiectasis with NTM-PD. * Diagnosed with other chronic respiratory diseases considered primary conditions, rather than bronchiectasis. * Participants with a history of NTM pulmonary infection. * NTM-negative results obtained before 2024.