[Two patients with hypereosinophilic syndrome]

Persistent eosinophilia was diagnosed in a 19-year-old woman with general malaise, dyspnoea attacks, coughing and episodes of angioedema and associated swallowing problems, and in a 21-year-old man with visual problems, dyspnoea, fatigue, reduced appetite, weight loss and gastrointestinal problems. Both had hypereosinophilic syndrome (a rare disease) with organ damage. In both patients, fluorescence-in-situ-hybridisation (FISH) was negative for the fusion gene FIP1L1-PDGFRA (FIPI-like-1-platelet-derived growth factor receptor alpha). The female patient's disease did not respond to either oral corticosteroids or imatinib, but did respond to hydroxycarbamide. The male patient successively received prednisone, interferon alpha and hydroxycarbamide. His eosinophilia progressed nonetheless, but responded partially to imatinib. In addition, the patient underwent an allogenic non-myeloblative stem cell transplantation from his HLA-identical sister. In patients with persistent eosinophilia accompanied by organ damage or organ dysfunction, hypereosinophilic syndrome can be diagnosed providing all secondary causes of the eosinophilia have been ruled out. Complementary investigations should include cytogenetic and clonal analysis to rule out haemopoietic malignancy. Prednisone, hydroxycarbamide, interferon alpha and the promising imatinib are all treatment options.