Primary Ciliary Dyskinesia (PCD)

www.thoracic.org C LI P A N D C O P Y What causes PCD? PCD is an inherited disorder, meaning that people born with the disease receive a mutated (abnormal) gene from both parents. In PCD, mutations in the genes responsible for building cilia and controlling their function result in cilia that do not work effectively. Dyskinesia, or impaired movement, is the most common ciliary defect seen in PCD. Other defects may lead to not having enough cilia on each airway cell, which can also cause the clinical symptoms seen in PCD. Motile cilia are very complex organelles (little organs) and are outgrowths on the surfaces of cells that line the upper (ears, nose and throat) and lower (lungs) respiratory tract. Each of these cells contains approximately 200 cilia that normally beat very fast in a coordinated fashion. Cilia are covered by a mucus “blanket” that traps unwanted inhaled particles and germs. The beating cilia underneath this blanket move the mucus to larger airways and the back of the throat where it is coughed out or swallowed. This is called mucociliary clearance and is one main way our bodies defend our lungs and maintain good respiratory health. Without properly functioning cilia, mucociliary clearance is severely impaired, and germ-filled mucus stays in the ears, nose, sinuses, and airways of the lungs, causing inflammation and repeated infections. In addition to problems with mucociliary clearance, people with PCD can have abnormalities in the development or placement of their internal organs because the special cilia that direct placement of these organs do not move normally. Therefore, abdominal organ placement might be: