Lung Transplantation in Cystic Fibrosis

Lung transplantation has become a viable option for those cystic fibrosis (CF) patients with end-stage lung disease. Despite the challenges that the CF patients present, the survival seen after lung transplantation is more favorable than seen in patients with chronic obstructive pulmonary disease and pulmonary fibrosis. Although the CF patients with severe respiratory disease usually are infected with organisms that display in vitro resistance to the commonly used antibiotics, these patients usually have successful outcomes with transplantation. The other challenges include the presence of nontuberculous mycobacteria, the significant incidence of liver involvement, the development of an Hens or the development of the distal intestinal obstruction syndrome, and the presence of gastroesophageal reflux. Most of the patients have metabolic bone disease, even pre-operatively, that warrants treatment, especially with the significant loss of bone density seen in the first year after transplant, thought to be related, in part, to the high dose of corticosteroids. Diabetes mellitus and its consequences are not uncommon. The malabsorption of fat seen in the pancreatic-insufficient patients complicates the absorption kinetics of the anti-rejection drugs. In May 2005 the United Network of Organ Sharing instituted a lung-allocation score to better distribute the donated lungs to those patients who would achieve the most benefit. This score uses several variables to balance the likelihood of the patients living one year with a transplant versus one year without a transplant. With this change in the allocation of organs, the median waiting times have significantly decreased, the mortality on the waiting list has decreased, and the number of CF patients transplanted has not changed. With substantial experience, more programs are now transplanting patients who require constant mechanical ventilation or patients who have undergone previous pleural procedures, especially in the treatment of a pneumothorax. The limiting factor now in lung transplantation is the number of organs available. Efforts to increase the donor pool, such as alveolar recruitment strategies to improve gas exchange, have been effective in allowing more patients to be transplanted. Lung transplantation is now an accepted form of therapy in those patients who are developing progressive respiratory failure.