[Acute idiopathic eosinophilic pneumonia in a teenager].

Acute idiopathic eosinophilic pneumonia is a very rare cause of interstitial lung disease in children. Pathophysiological mechanisms and etiology remain poorly understood. It manifests as a febrile dyspnea, progressively worsening. Chest X-ray, performed as first-line, shows bilateral infiltrates. The chest CT confirms a diffuse infiltrative pneumopathy and the bronchoalveolar lavage demonstrates the presence of alveolar hypereosinophilia. The exclusion of other causes of alveolar eosinophilia confirms the diagnosis. A ventilatory support is very often necessary. Systemic corticosteroids provides a spectacular clinical improvement, without recurrence.