The outcomes of sickle cell disease in adulthood are clear, but the origins and progression of sickle cell anemia-induced problems in the heart and lung in childhood are not.

摘要

Individuals with sickle cell anemia (SCA) have a shortened life expectancy when compared with ethnic matched controls. Two well-documented etiologies of this reduced life span are chronic lung disease and pulmonary hypertension. The Cooperative Study of Sickle Cell Disease, a multicenter natural history study, identified acute chest syndrome (ACS) as a leading cause of premature death. Recurrent ACS is a significant, independent risk factor associated with sickle cell lung disease (SCLD).2 Powars et al suggest that SCLD, an important cause of death in adults with sickle cell disease (SCD), is progressive and results in pulmonary hypertension in the later stages of disease. Further, the importance of pulmonary hypertension as a risk factor for death was recently highlighted by Gladwin et al, who found that pulmonary hypertension as indicated by a tricuspid regurgitation jet velocity >2.5 m per second is a predictor of death among persons with SCD. The progression of SCLD to pulmonary fibrosis suggests that recurrent ACS may be associated with restrictive lung disease, and in adults, restrictive lung disease has been the predominant pattern of pulmonary function abnormality.2,4 However, the relationship between ACS and lung function is unclear, as other studies have found both restrictive and obstructive changes. Some of this confusion may relate to the age at which subjects are studied, with adults presenting with a more restrictive picture, whereas children appear more obstructive.7