[Hypereosinophilic syndrome in acute lymphatic leukemia].

Acute lymphatic leukemia (common-ALL-Ag positive) was found to be the underlying disease in a 4-year-old boy with arthropathy, generalized rash and marked eosinophilia. ALL may be overlooked in the early stages. Cytochemical, chromosomal and immunological markers are needed to distinguish it from other leukemias. As shown by the data of 25 patients from the literature, hypereosinophilic syndrome (HES) influences morbidity and lethality. Hydroxyurea rapidly lowers the eosinophil counts and may therefore prevent the cardiac involvement typical of HES.