Lung transplant

Question

If a patient undergoes lung transplant do these lungs stay clear of CF? Or is there in the long term also building up of sticky secretions?

Answer

Cystic fibrosis (CF) is a genetic disorder and this implies that the abnormality is in a specific gene and is being inherited. In CF there is a problem in all the cells of the respiratory system. A genetic error causes disturbed salt and water balance and sticky secretions. This leads to airway infections and lung damage that can necessitate a lung transplant.

If a donor receives new lungs via transplant, the cells of these new lungs do not have CF because they have the normal genetic code of the healthy donor and their salt and water balance functions normally. The genetic code of the donor lungs does not change after transplant. As a consequence a CF patient who receives a lung transplant is for ever cured of these defective lung cells. CF can also never reoccur in the transplanted lungs. The symptoms as a cause of CF in the other organs however continue to exist (poor digestion, diabetes, fertility problems, …).

This does not exclude that after lung transplant other lung problems occur in this subject. In case of transplant a foreign lung is being implanted. To prevent rejection of these foreign lungs the immune system is inhibited by medicines (immune suppressive drugs). This suppression of the normal immune system causes greater susceptibility to infection. Infection can then again lead to build up of sputum. In a minority of patients after lung transplant there will be a narrowing of the large airway (bronchial stenosis) or a malfunctioning of the airways (tracheobronchomalacia) or a permanent dilatation of the airways (bronchiectasis). These can again lead to difficulties with coughing up secretions and repeated infections. Also chronic rejection can induce sputum production. These new lung problems need to be treated appropriately and this treatment is of course quite different from the treatment of CF lung disease.
To conclude: after lung transplant lungs stay clear of CF but not always clear of secretions. After transplant, an optimal follow up and a timely treatment in case symptoms occur is absolutely necessary.
Pieter Goeminne, Lieven Dupont

15.11.2010