CF and tracheamalacia

Question

Do people with CF have an increased risk of tracheamalacia ? Is the treatment the same ? Is there a link between CF and tracheamalacia ?
Is it a disadvantage to have CF and tracheamalacia ?

Answer

Thanks for your interesting question. The word tracheamalacia means “floppy trachea”. (the trachea is the large airway). This medical term is being used in case the large airway or trachea is floppy and collapses during couching or with forceful expiration.
A normal trachea has a horse shoe form and is supported by cartilage rings on the front and sides. The backside of the trachea has a muscle layer. Tracheamalacia can occur when there is abnormalities of the cartilage or of the muscular posterior part. This will lead to loss of the normal tracheal rigidity. Tracheamalacia can be congenital or acquired. Congenital tracheamalacia can be an isolated problem or be part of other congenital abnormalities. It is for instance well known that children with problems of the esophagus will often have tracheamalacia. Tracheamalacia can also be an acquired problem. Prematurity with long term need for artificial ventilation is a known risk factor to develop tracheamalacia, to give an example. Also recurrent infections of the airways are a predisposing factor to the develop tracheamalacia. In case of tracheamalacia the typical complaints are a barky cough and difficulties with coughing up sputum, especially at times of infection. Patients can have noisy breathing during inspiration as well as during expiration. In some children there may be asthma like symptoms such as wheezing. In case of severe tracheamalacia there can be suffocating coughing spells. The diagnosis of tracheamalacia is being made more often, not only because the problem becomes more prevalent but also because there are better ways to diagnose it. The first choice diagnosis is a direct examination of the airway (bronchoscopy) in a patient who is sedated but it is still breathing spontaneously. When during coughing the trachea collapses or diminishes in caliber by more than 15%, one speaks of tracheamalacia. Alternative diagnostic methods are a CT scan during in- and expiration or newer techniques such as dynamic CT. The treatment of tracheamalacia is non specific. It mainly means preventing and treating infections with antibiotics and chest physiotherapy with aids such as a PEP-mask.
Is there a link between CF and tracheamalacia ?
A patient with CF can have a congenital tracheamalacia just like any other patient. Severe problems after birth with need of long term ventilation can occur in CF and would also be a risk factor for tracheamalacia in that patient. But there are data who show that tracheamalacia is more frequent in patients with cystic fibrosis, especially in adult CF patients. The suspicion is that it mainly concerns acquired tracheamalacia as a consequence to chronic infection of the airway. This will necessitate an adapted form of chest physiotherapy.

Is it a disadvantage to have CF and tracheamalacia ?
Severe tracheamalacia is certainly a disadvantage in a patient with cystic fibrosis. In CF there is chronic infection and abundant mucus. It is thus very important that mucus can be expectorated efficiently. Airway clearance will occur more difficult in a patient with CF and tracheamalacia. The second disadvantage is that patients with tracheamalacia will have difficulty to perform lung function tests correctly. When they expire with full force, the trachea will collapse partially and the maximal speed of expiration will be underestimated. It is thus difficult to interpret FEV1 and peak flow measured by spirometry in a subject with CF and tracheamalacia, it might be an overestimation of the severity of lung disease.

I hope this clarifies something for you.
Prof. Dr. M. Proesmans

04.10.2010