ABSTRACT
Hypereosinophilic syndrome is a heterogeneous disease characterized by eosinophilic tissue inflammation and eosinophilia. Pulmonary involvement could be seen in up to 55% among children with hypereosinophilic syndrome. A 3-year-old boy with chronic hypereosinophilia and respiratory complaints was diagnosed with idiopathic hypereosinophilic syndrome. Atelectasis was detected in the radiological evaluation, and bronchial casts with eosinophilic structures were removed by bronchoscopy. Steroid, inhaled hypertonic saline, inhaled bronchodilator, inhaled corticosteroid, and leukotriene receptor antagonist were used for 1 year in the management of hypereosinophilic syndrome, and related eosinophilic casts and repetitive bronchoscopies were administered for removal of the casts. The patient was successfully managed with an inhaled N-acetyl cysteine treatment. In children, the long-term prognosis of hypereosinophilic syndrome is uncertain. Comprehensive diagnostic tests are required for the early diagnosis and management of pediatric hypereosinophilic syndrome. In the presented case, the rare occurrence of pulmonary involvement of hypereosinophilic syndrome in a 3 year-old-boy with recurrent hypereosinophilic casts and its management were discussed.