Introduction: Idiopathic hypereosinophilic syndrome is an uncommon disease often associated with diverse non-specific skin manifestations. Mucosal ulcerations suggest a myeloproliferative from with poor prognosis due to possible progression to malignant hemopathy or visceral complications.
Case report: A 28-year-old man presented idiopathic hypereosinophilia with isolated mucosal ulcerations involving the buccal and genital areas. Laboratory results (hematology, CD25) suggested a myeloproliferative form. Treatment with alpha interferon (18 months) led to regression of the mucosal lesions and a decrease in the markers of eosinophil toxicity. There was no visceral involvement.
Discussion: Immunosuppression with/without high-dose alpha interferon is usually used for the treatment of hypereosinophilic syndrome. In our case favorable outcome was obtained with lower doses of alpha interferon than those reported in the literature. There was objective decrease in eosinophil toxicity (regular counts of hypodense eosinophils, CD25 or interleukin 2 soluble receptor) and no progression (malignant hemopathy, mortal visceral involvement).