Bronchiectasis is a type of lung condition in which the lungs' airways are abnormally stretched and widened. This stretching and widening makes it difficult for mucus and other substances to move out of the lungs, encouraging the growth of bacteria and leading to breathing problems or infection. Bronchiectasis can be caused by genetic disorders or diseases such as tuberculosis or rheumatoid arthritis. Researchers are interested in developing better ways to diagnose and treat a lung problem called idiopathic or unexplained bronchiectasis.
About this Study
The first protocol of the Genetic Disorders of Mucociliary Clearance Consortium focused on airway diseases with a known genetic etiology: primary ciliary dyskinesia (PCD), variant cystic fibrosis (vCF), and pseudohypoaldosteronism (PHA). This second GDMCC protocol will study adult patients with non-CF, idiopathic bronchiectasis, whose genetic etiologies are not known. Idiopathic bronchiectasis is reportedly more common in females with certain tall, thin body types and associated with environmental organisms, such as nontuberculous mycobacterium (NTM). The gender other susceptibility factors predisposing to bronchiectasis or acquisition of NTM are unclear. The study will attempt to broaden the understanding of this disease by comparing gender-associated factors and NTM status. A relatively equal number of both females/males and NTM/non-NTM infected subjects will be enrolled. Approximately 300 people may be screened to find 260 eligible subjects since a small number (e.g., 40 patients) may be diagnosed with PCD, vCF, or other known etiology as an explanation for the bronchiectasis.
This single-visit protocol will use a systematic approach to characterize the physical features, radiographic patterns, and associated lower airway microbial flora. There is no natural history of disease course follow-up component to this protocol. Participants will have one outpatient clinic visit for evaluation with a physical examination including detailed body size measurements, medical history, collection of blood samples for routine lab tests and genetic analyses, and a chest x-ray if no recent one is available. Participants will also have tests of lung function, and measurement of a gas called nitric oxide in the nose. Participants whose initial tests show abnormal results may also be asked to have a nasal scrape to collect cell samples and/or a skin sweat test to measure salt concentrations. Participants will also have a sputum specimen collected during the visit and will be asked to collect two additional early morning sputum samples and a mouth rinse at home within 2 weeks of the clinic visit, and mail the sample collection materials to the research team.
Careful evaluation and characterization of the physical and clinical characteristics will guide the genetic characterization of idiopathic bronchiectasis, and likely lead to an improved diagnostic approach. Identification of disease causing genes may provide new therapeutic targets.
To be eligible to participate, you must:
- Be an individual with one of the following:
- The criteria for participants to enter the study mandates that each patient have received a standard (current clinical practice) diagnostic evaluation that includes a CT scan of the chest to document bronchiectasis, prior to enrolling in the Consortium study. To enter this protocol, adults must have bronchiectasis and meet the following criteria:
- Males or females, age greater than or equal to 18 years
- Chronic cough
- An available CT of the chest (on a CD) that shows evidence of dilated airways fulfilling radiographic criteria for bronchiectasis in more than one lobe
- Ability to provide informed consent, including HIPAA consent
You are not eligible to participate if:
- A participant should not be in the study if they have not had a standard clinical evaluation to rule out other potential causes of chronic sino-pulmonary disease or if any of the following are present:
- Known diagnosis of cystic fibrosis with classic clinical presentation and elevated sweat chloride levels and/or two known disease-causing CFTR mutations
- History of tuberculosis or other known explanation for bronchiectasis, such as alpha 1-antitrypsin deficiency (ZZ or ZS), confirmed or probable PCD, inflammatory bowel disease, rheumatoid arthritis, Sjögren's syndrome, allergic bronchopulmonary aspergillosis, or documented primary or acquired immunodeficiency
- Current smoker or > 10 pack-year history of tobacco use
- Prior solid organ transplant