Hypereosinophilic syndrome: correlation between clinical severity and cutaneous microthrombi

A 32-year-old man, with a 12-year history of recurrent edema of the upper a nd lower extremities, was admitted in February 1998 due to edema of the rig ht forearm and tiredness of 1-month duration. Examination revealed an ill-d efined, itchy, slightly erythematous, indurated patch with excoriation on t he right forearm (Fig. 1). There was no history of drug intake, atopy, or a sthma. He recalled, however, having experienced cold-induced Raynaud's phen omenon and intermittent arthralgia. In laboratory tests, there was a white cell count of 11.77 X 10(3)/muL with 48% eosinophils (4830/muL), Liver func tion tests showed elevated serum glutamic pyruvic transaminase (SGPT) and a lkaline phosphatase, Rheumatoid factor was positive. Total immunoglobulin E (IgE) concentration was elevated to 4703 U/mL (normal, < 378 U/mL), while other serum immunoglobulins, including IgG, IgA, and IgM, were normal. Bone marrow aspirate and biopsy showed normocellular marrow with an excess of m ature eosinophils, but no evidence of blast cells. There was no evidence of parasitic infestation, and allergy skin test was negative. An extensive sy stemic evaluation showed no other organ involvement. A skin biopsy specimen revealed many eosinophils infiltrating the perivascular, periappendageal, and subcutaneous fat area and also within the vessel walls. Multiple microv ascular thrombi with eosinophils were observed in the mid and lower dermis and subcutaneous fat (Fig. 2). The eosinophils showed positive staining wit h eosinophil cationic protein (ECP) using the monoclonal antibody EG2. On t he basis of the above findings, we diagnosed hypereosinophilic syndrome (HE S). Treatment with 60 mg prednisolone daily was started and, within 7 days, his edema and itching sensation started to resolve. Follow-up laboratory a nd biopsy findings after 1 month returned to normal, The prednisolone dosag e was slowly tapered over a 9-month period and he is currently on a mainten ance dose of prednisolone 10 mg alternate day therapy.