[Acute respiratory failure revealing an idiopathic acute eosinophilic pneumonia: report of a pediatric case]

Hyperleucocytosis as an unusual presentation of hypereosinophilic pneumonitis with acute respiratory distress syndrome

Idiopathic hypereosinophilic syndrome in children is a rare disease. Even with improved understanding of eosinophilic disorders and recent advances in diagnostic modalities, evaluation of hypereosinophilia remains challenging due to heterogeneous etiologic factors. In acute clinical settings, the management plan is often unclear as the condition is not encountered frequently. It is often associated with leucocytosis, but hyperleucocytosis causing multiorgan dysfunction in the absence of malignancy is rarely seen. A previously well 5-year-old boy presented to our emergency room with a 2-week history of fever, progressive cough and dyspnoea, rapidly progressing to respiratory failure and acute respiratory distress syndrome. Hyperleucocytosis with hypereosinophilia on peripheral blood film, bilateral pulmonary infiltrates on X-ray and ground glass opacities suggested hypereosinophilic syndrome with secondary acute respiratory distress syndrome. Owing to severe and rapidly increasing leucocytosis, malignancy was highly suspected, but it was ruled out along with secondary hypereosinophilic syndrome after extensive investigations, and acute respiratory distress syndrome in this child was attributed to Idiopathic Hypereosinophilic Syndrome. Eosinophilia had a dramatic response to high dose corticosteroid therapy. To conclude, in patients with hypereosinophilic syndrome, possibility of progression to acute respiratory distress syndrome should be anticipated and managed accordingly.

Idiopathic eosinophilic pneumonia in children: the French experience

Background

Idiopathic eosinophilic pneumonia is extremely rare in children and adults. We present herein the first series describing the specificities of idiopathic chronic (ICEP) and acute (IAEP) eosinophilic pneumonia in children.

Methods

We retrospectively analyzed all cases of ICEP and IAEP in children that were retrieved from French Reference Centers for rare pediatric lung diseases.

Results

Five cases of pediatric ICEP were identified. Corticosteroid or immunosuppressive therapy dramatically improved the outcome in three cases. The remaining two cases had a persistent interstitial pattern with progressive development of cystic airspace lesions. Three cases of IAEP in adolescents were reported, with one requiring four days of extracorporeal membrane oxygenation.

Conclusion

ICEP is a rare disease with a polymorphic clinical presentation in children. We identified patients with persistent interstitial patterns progressing to cystic airspace regions, for which the boundaries with idiopathic interstitial pneumonias are difficult to establish. We therefore propose a specific pediatric definition and classification algorithm. IAEP in children remains an inflammatory reaction of the lung to an acute toxic exposure, mainly tobacco, as in adults. International studies are required to comprehensively assess the various clinical forms of the disease as well as the appropriate therapeutic regimens.