Nouvel appareil pour dépister une maladie pulmonaire insaisissable

L’HME sera le deuxième centre en Amérique du Nord à offrir le dépistage clinique de la dyskinésie ciliaire primitive

Primary Ciliary Dyskinesia (PCD) is an inherited disorder of the cilia, little microscopic hairs that line the lungs, nose and ears. Patients who are born with this disease suffer from chronic lung, sinus and ear infections. If not treated early, the disease can cause progressive lung damage or even death. Until now, diagnosis of this disease has been difficult. Fortunately, the Montreal Children’s Hospital (MCH) now has a new diagnostic tool, a nasal nitric oxide machine, to screen for PCD. The MCH will be only the second centre in North America to provide clinical screening for this chronic disorder.

“The problem with PCD is that so many diseases in respirology look like it,” says Dr. Adam Shapiro, a pediatric respirologist at The Children’s. “If you miss a PCD diagnosis in children and find it when they are older, they have significant lung damage and even increased mortality. On the other hand, if we catch the disease early, we can treat it and the children have the potential of living normal lives.”

What cilia do

Cilia are found throughout the entire respiratory tract, including the nose and lung and ears. Normally, they constantly beat back and forth to propel mucous and other inhaled elements (dust and pollution) up to the top of the airway where they can be easily cleared. “Cilia are the street sweepers of the lung,” says Dr. Shapiro.

When cilia stop working, in diseases such as PCD, mucous collects and provides an ideal breading ground for bacteria. Chronic infections commonly result, leading to lung damage and progressive respiratory failure.

Nitric oxide the key

The nasal nitric oxide machine will simplify screening and diagnosis of PCD. It measures nitric oxide, which is exhaled through the nose. For reasons unknown, the exhaled nitric oxide levels are very low in PCD. “If a patient has high levels of nitric oxide, we know it’s not PCD, but if they are low, we are quite suspicious of PCD, and we will perform further investigations for it. This non-invasive screening test takes only five minutes to complete and will really impact PCD patient’s lives. It can be easily performed in children above 1 year of age”  

PCD is treatable

There are two mainstays of treatment for PCD; airway clearance and antibiotics. Children who have a PCD diagnosis usually visit the PCD clinic every three months to learn exercise and breathing skills that help them clear their airways. “These techniques are particularly important to learn, they are really life-saving,” says Dr. Shapiro.

These patients are also monitored for infections and treated with antibiotics as necessary.

“Having this diagnostic capability will really put us on the map,” says Dr. Shapiro. The machine will be housed in the MCH’s pulmonary function lab.

Symptoms of PCD

  • Year-round, daily wet cough, starting in infancy
  • Year-round, daily nasal congestion, starting in infancy
  • Recurrent ear infections, starting in infancy
  • Recurrent bronchitis or pneumonia
  • 85% of PCD patients have respiratory distress at birth
  • 50% of PCD patients will have their organs flipped in mirror image (eg. their heart is on right side instead of the left), and at least 6% will have other rare organ defects associated with congenital heart defects (Heterotaxy)