Lung Transplantation in Cystic Fibrosis: Trends and Controversies

Abstract

This article is not an overview of all facets of lung transplantation in cystic fibrosis (CF), but rather it is intended as a review of current allocation controversies, as well as of trends in diagnostics and management in lung transplant recipients and in patients with end-stage lung disease. Despite changes in donor and recipient selection, long-term survival in pediatric lung transplant has continued to be limited by chronic lung allograft dysfunction (CLAD). Due to, in part, this short survival benefit, transplant continues to be an appropriate option for only a subset of pediatric patients with CF. The feasibility of transplant as a therapeutic option is also affected by the limited pediatric organ supply, which has moreover contributed to controversy over lung allocation. Debates over the allocation of this scarce resource, however, may also help to drive innovation in the field of lung transplant. Longer pretransplant survival-as aided by new lung bypass technologies, for example-could help to alleviate organ shortages, as well as facilitate the transport of organs to suitable pediatric recipients. Improved diagnosis and treatment for CLAD and for antibody-mediated rejection have the potential to extend survival in pediatric lung transplant. Regardless, the relative rarity of transplant could pose future challenges for pediatric lung transplant programs, which require adequate numbers of patients to maintain proper expertise.

FIG. 1.

Contrast between the percentage of under 12-year-old child donors providing lungs each year, compared to the percentage of adolescent donors.

FIG. 2.

Patterns of lung transplantation, by Diagnosis Group, in the era following implementation of the Lung Allocation Score. Diagnosis Group A includes obstructive lung diseases (such as chronic obstructive pulmonary disease), Group B includes pulmonary vascular disease, Group C includes cystic fibrosis (and immune deficiency), and Group D includes restrictive lung diseases (such as idiopathic pulmonary fibrosis). In this graph, each “year of transplant” starts in May (eg, 2004 runs from May 4, 2004 to May 3, 2005).

FIG. 3.

Experience of pediatric lung transplant centers, by year. The last year in which International Society for Heart and Lung Transplantation (ISHLT) has reported centers performing 20 or more transplants was 1998. In 2012, ISHLT reported that no centers performed more than 9 transplants (ISHLT data, adapted from Benden et al.).