Background

The hypereosinophilic syndrome (HES) is defined by an eosinophilic count > 1500 cell/mm3 and organ damage or dysfunction that can be easily mistaken for atopic dermatitis or pulmonary pathologies. Timely diagnosis and treatment can improve the prognosis and avoid heart and renal complications or lung fibrosis.

Case report

The case of an infant is reported with a 24-h evolution of cough and fever, personal history of atopic dermatitis, and a generalized dermatosis 2 months earlier. In the initial approach, respiratory disease was considered. However, blood count reported hypereosinophilia, which led to further studies and the diagnosis of the HES.

Conclusions

Although a rare pathology, it is important to consider the HES in children with common symptoms, and unusual evolution or poor treatment response and persistent hypereosinophilia.