Mucociliary Clearance Consortium (MCC) Rare Genetic Disorders of the Airways: Cross-section Comparison of Clinical Features, and Development of Novel Screening and Genetic Test
We have established a consortium of 7 geographically-dispersed clinical research sites that are designed to study rare diseases of the airways, which involve defects in clearance of mucus secretions from the airways (defective "mucociliary clearance"). These sites will collaborate in diagnostic, genetic, and other studies in patients with impairments of mucociliary clearance, including primary ciliary dyskinesia (PCD), variant cystic fibrosis (CF), and pseudohypoaldosteronism (PHA). These disorders reflect genetic defects in airway host-defense, and typically result in chronic infection of the airways. Patients with these disorders of the conducting airways and sinuses have delayed (or incorrect) diagnoses, because diagnostic tests are not readily available. These patients may also have sub-optimal management of their clinical disease, because the cause of these disorders is not well-defined, and treatment regimens are usually not driven by evidence-based medicine.
This current protocol is designed to employ a systematic approach to the diagnostic evaluation of these patients with chronic airways disease, which will yield precise diagnoses in individual patients, and will be associated with development of better diagnostic techniques, including genetic testing. In addition, we will compare/contrast clinical features (phenotype) across these disorders. A rigorous cross-sectional comparison of the clinical features will provide better understanding of the clinical disease of these disorders; in turn, this will lead not only to a better standard of clinical care, but will also assist in the identification of novel therapeutic approaches.
The patient population for these studies includes individuals carrying a tentative diagnosis of the three disorders (PCD, variant CF or PHA), plus individuals suspected to have one of these disorders, but with inadequate or inconclusive diagnostic tests. Individuals in this latter category must have a preliminary clinical evaluation to evaluate for other more common disorders that may have similar manifestations including classical CF, immunodeficiency, asthma, and severe gastroesophageal reflux. We have an informal agreement with a network of pulmonologists across the United States to perform clinically-indicated (not research) preliminary clinical testing, if not directly available to patients who inquire about these studies.
Blood will be collected for DNA to test for genetic mutations. The blood samples will be processed to establish a cell line (lymphocyte transformation) for a source of DNA for future genetic studies, in participants with disease. For participants unable to provide a blood sample, a buccal sample will be obtained for DNA.
- Type: Cross-Sectional
- Archiver: The database of Genotypes and Phenotypes (dbGaP)