[Acute chest syndrome in sickle cell disease and acute respiratory distress syndrome--from pathophysiology to therapy].

Acute chest syndrome is frequent in the homozygous sickle cell disease population. It can evolve to an acute respiratory distress syndrome. Pulmonary artery hypertension or chronic lung sequellae are common. The vasoocclusive phenomenon is due to capillary blockade, followed by an activation of inflammation, and adhesion phenomena further increasing the damage. Decreased blood oxygenation leads to an aggravation of the sickle crisis. Nitric oxide disregulation has been recently highlighted. Diagnosis must be suspected in patients presenting with sickle crisis, fever, low blood oxygenation and lung infiltrates. Early antibiotherapy, adequate oxygenation, blood transfusion and erythrocytapheresis are key points for management. Preventive measures such as iterative transfusion-chelation, hydroxyurea or repetitive erythrocytapheresis are all useful.