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Research associate Kunal Chawla (left), and Dr. Margaret W. Leigh measure nasal nitric oxide in research participant Kaylee Ollis.
N.C. Children's Hospital contact: Danielle Bates, 919-843-9714, firstname.lastname@example.org
PCD Foundation contact: Michele Manion, 612-386-1261, email@example.com
Wednesday, June 27, 2012
Clinicians and medical scientists at the University of North Carolina School of Medicine have long been renowned for exemplary research and clinical care programs for cystic fibrosis. Lesser known is their leadership in advancing the research and treatment of another rare pulmonary disorder, primary ciliary dyskinesia, or PCD. The relatively rare inherited disease is estimated to affect as many as 25,000 Americans, most of them completely unaware they have the condition.
“Maybe 10 percent of the PCD population is currently diagnosed, so there are tens of thousands of people out there who have it and have no idea,” said Michele Manion, executive director and founder of the PCD Foundation, the only North American patient advocacy group for PCD. “Many think they have severe asthma. Some are told they have idiopathic bronchiectasis, but many don't learn they have an underlying genetic lung disease until they get to the point of transplant.”
UNC physicians and scientists are teaming with the PCD Foundation this weekend to present the 10th annual PCD Family Day, a weekend-long family education program taking place at the Millennium Hotel in Durham, N.C., Friday through Sunday (June 29-July 1). The event will welcome nearly 150 people representing more than 40 families from across the country affected by the disease. The goal of the weekend is to update attendees on research progress and advances in treatment and provide a forum for people affected by PCD to share information and support.
As the name implies, primary ciliary dyskinesia affects the function of cilia, the microscopic hair-like structures that line the airway and beat in unison to sweep the lungs clear of dust and secretions trapping disease-causing organisms. Impairment of this biological cleansing mechanism boosts risk of illness and can lead to chronic airway disease and infertility, among other conditions.
Accurate diagnosis is compounded by several factors, according to Dr. Margaret Leigh, professor of pediatrics at the UNC School of Medicine and director of the UNC Cystic Fibrosis Clinical Care Center, who chairs of a five-year, multi-center longitudinal study evaluating the progression of lung disease in children with PCD.
“Although the incidence is not all that different than that of cystic fibrosis, PCD is misunderstood and considered so rare, it’s often not even considered,” said Leigh, who is also co-principal investigator of the Genetic Disorders of Mucociliary Clearance Consortium within the Rare Diseases Clinical Research Network. “And while the diagnosis remains technologically very challenging, we’ve found very clear clinical markers of disease—some 90 percent of infants born with PCD have respiratory distress, which can be fatal, and 50 percent of affected individuals will have organ placement anomalies. People with PCD also have 200 times the risk of having congenital heart defects.”
Biopsy of ciliary ultrastructure by transmission electron microscopy (TEM) analysis at research institutions like UNC has been the gold standard in PCD diagnosis for many years, but genetic testing remains the wave of the future. To that end, Dr. Maimoona Zariwala has led UNC research focused on identifying PCD genes in collaboration with researchers around the world, making great strides in understanding the genetic aspects of PCD. Published studies have so far identified mutations affecting 14 genes, with more on the horizon. Comparatively, cystic fibrosis involves mutations to a single gene.
“Many genes participate in the construction of cilia, hence PCD is a genetically heterogeneous, or complex, disorder,” said Dr. Michael Knowles, professor of medicine and co-director of the Cystic Fibrosis Program at UNC. “That makes it challenging to define its genetics, because mutations in more than one gene and different mutations in the same gene can cause the disease.”
According to the PCD Foundation, one in 63 people is a PCD carrier and current genetic tests to detect PCD are only about 60 percent accurate. These are facts that make the research going on at UNC all the more critical for the tens of thousands living with undiagnosed PCD.
“UNC is the undisputed premiere center for PCD research and care in the United States,” said Manion, who started the PCD Foundation in the years after her daughter was diagnosed with the disease at age 7. “Without their leadership, we would not have our current seven-site research network, which has been responsible for rapidly advancing knowledge of PCD genetics and natural history.”
“UNC has also been instrumental in creating international research collaborations that are helping to redefine this poorly understood condition,” added Manion. “Because of these efforts, we have better methods for diagnosis and are identifying potential targets for therapies to help patients in the future.”
According to Dr. Leigh, clinicians and researchers at UNC follow more than 50 patients with PCD, about half of them children, and have evaluated another 400 or more people with PCD or presumed PCD from around the country through clinical visits and research studies. Several families involved in PCD Family Day will also visit UNC for one or more research studies while in the Triangle.
The media is invited to cover the events of PCD Family Day and are asked to RSVP in advance to Michele Manion (firstname.lastname@example.org or (612) 386-1261). Complete program details available at http://bit.ly/PCDFamilyDay2012.