Screening for Cystic Fibrosis and Cystic Fibrosis Related Disorders in Chinese Adults With Bronchiectasis

Study Overview
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Brief Summary
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The study carries out Sweet Tests and CFTR-mutation screening to explore the prevalence, clinical characteristics, and prognosis of cystic fibrosis, as well as the CFTR-mutation spectrum in Chinese adults with bronchiectasis. The study is multi-centered, prospective, non-interventional, and observational.

Detailed Description
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The incidence of cystic fibrosis (CF) or CFTR dysfunction in China remains unclear due to the absence of a diagnosis and different genetic backgrounds. However, the CF case rate in western countries is relatively high, up to 1/2500. According to the limited statistics, the most common classic clinical symptom of Chinese CF patients is bronchiectasis. Other symptoms often seen in diseased western groups, such as pancreatic insufficiency, are rarely seen in Chinese patients. Thus, Chinese CF or CFTR dysfunction patients easily misdiagnose bronchiectasis, Chronic pneumonia, asthma, etc. Sweet test and CFTR-mutation screening are urgently needed for diagnosing and treating CF or CFTR dysfunction patients in Chinese adults with bronchiectasis. The study will focus on the change in CFTR function, genetic susceptibility factors, and disease progression to explore the incidence, clinical characteristics, and prognosis of cystic fibrosis, as well as the CFTR mutation spectrum in Chinese adults with bronchiectasis.

Official Title
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The Clinical and Genetic Characteristics of Cystic Fibrosis and Cystic Fibrosis Disorders in Chinese Adults With Bronchiectasis

Conditions
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Cystic Fibrosis, Pulmonary

Intervention / Treatment
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* Diagnostic Test: Sweat Test


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age>18 years, the diagnosis of bronchiectasis needs a reference to the definition of non-cystic fibrosis bronchiectasis guideline published by the British Thoracic Society in 2017 or 2021 China bronchiectasis expert consensus, clinical symptoms of cough and expectoration, with or without intermittent hemoptysis, and chest CT showed bronchiectasis Patients who are willing to sign the consent form and participate in the study. Exclusion Criteria: Patients with incomplete essential information, which is needed for the integrity of data analysis. Essential information includes CT images, respiratory sample cultures, spirometry, and exacerbation history for at least one year. Patients under 18 years old. Sweat Test Exclusion Criteria: Patients with an implanted device, such as a defibrillator, neurostimulator, pacemaker, or ECG monitor. Patients with a history of epilepsy or seizures. Patients who are pregnant. Patients that have a known sensitivity or allergy to any ingredient. Over-damaged, denuded skin or other recent scar tissue. Patients with Cardiac Conditions or with suspected heart problems.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Adult patients with bronchiectasis (unknown cause)<br>Diagnosis of bronchiectasis was performed using chest HRCT scans in suspected patients with coughing and expectoration, or long durations of hemoptysis. High-resolution images were obtained during full inspiration at 1-mm collimation and 10-mm intervals from the apex to the base of the lungs. The presence of bronchiectasis was confirmed based on the following criteria: 1) lack of tapering in the bronchi; 2) dilation of the bronchi where the internal diameter was larger than that of the adjacent pulmonary artery; or 3) visualization of the peripheral bronchi within 1 cm of the costal pleural surface or the adjacent mediastinal pleural surface. | Diagnostic Test: Sweat Test<br>* In people with cystic fibrosis (CF), there is a problem in the transport of chloride across cell membranes. This results in higher concentrations of chloride (as salt) in sweat compared to those who do not have cystic fibrosis. So, if there is a family history or a possibility of CF, the sweat test is part of the special tests to help make, or exclude, a diagnosis of cystic fibrosis.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Sweat chloride and conductivity | Sweat chloride and conductivity is the measured analyte most directly related to the abnormal function of the cystic fibrosis transmembrane regulator (CFTR), the chloride channel that is defective in cystic fibrosis patients | within 14 days after sweat collection | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| CFTR-mutation screening | CFTR-mutation screening will be carried out in Patients with abnormal results of Sweat Test. Mutation detection analysis will be performed in Next Generation Sequencing method using the genomic DNA extracted from peripheral whole blood. | 1 year |