Pulmonary complications in adult sickle cell disease

Sickle cell disease is an autosomal genetic condition which represents the most frequent genetic disease in ?le-de-France and Caribbean islands. The main clinical manifestations can be divided into infectious disease, hemolytic anemia and vaso-occlusive events. Pulmonary complications represent 20 to 30% of mortality due to sickle cell and can be divided into acute and chronic events. Acute chest syndrome (ACS) is an acute lung injury often preceded by a vaso-occlusive crisis and triggered by different factors including: hypoventilation, pulmonary infectious disease and vascular occlusions. These occlusions can be secondary to fat embolism, thrombosis or sickling. Treatment is mainly supportive combining oxygen supplementation adequate hydration analgesia and sedation. Exchange transfusion may be indicated in severe forms of ACS, characterized by a right ventricular dysfunction and acute respiratory failure. Pulmonary hypertension is the most serious chronic complication. Its frequency is estimated at 6% in adult patients and is more often described in patients with venous ulcers and higher levels of chronic hemolysis. Prognosis is poor with 12.5% of patients dying in the first two years following diagnosis irrespective of the actual pulmonary artery pressure level. There are currently limited data on the effects of any treatment modality. Other respiratory complications such as sleep disorders and nocturnal hypoxemia, infiltrative lung disease and exertional dyspnea are described and should be considered.