We report a case of idiopathic hypereosinophilic syndrome in a young child with favorable outcome after treatment with alpha-interferon.
Case report: A 5-month-old boy presented with major eosinophilia (187 G/l) associated with splenomegaly. There was no evidence for parasitic or allergic disease. Acute leukemia was suspected but bone marrow smear and medullary caryotype were not compatible. Idiopathic hypereosinophilic syndrome was thus diagnosed. Corticotherapy was started and failed. Finally, complete remission was obtained with alpha-interferon treatment.
Conclusion: Idiopathic hypereosinophilic syndrome is uncommon in children. Significant complications like cardiac dysfunction or hematologic malignancies can occur. Treatment has to be quickly started, in order to reduce eosinophilia. Haematological and echocardiographic follow-up are required.