A 54-year-old woman with chronic eosinophilic leukemia (CEL)

Chronic Eosinophilic Leukemia (CEL) is a rare myeloproliferative neoplasm characterized by clonal eosinophil proliferation. In a study involving 1,416 patients with eosinophilia evaluated between 2008 and 2019, only 17 (1.2%) met the WHO criteria for CEL. The incidence was 0.4 per 1,000,000 people/year from 2001 to 2020, increasing with age. The main complications include organ damage due to eosinophil infiltration and thrombosis. We report a case of CEL in a 54-year-old woman with generalized pruritus. The itching began suddenly 30 years ago without any trigger and persisted throughout the day, relieved only by medication. She denied any history of allergies and had consulted multiple dermatologists without improvement. Physical examination revealed no abnormalities. Laboratory findings showed leukocyte count 36,800, eosinophils72.4%, Hb 15, Plt 243,000, and blood smear suspected hypereosinophilic leukemia. BMP tests confirmed a chronic eosinophilic leukemia diagnosis. The patient was treated with oral prednisone 5 mg, 4 tablets/12 hours, resulting in symptom relief and normalization of eosinophil levels. CEL manifestations include fatigue,cough, dyspnea, myalgia, rash, and rhinitis. Cutaneous manifestations are rare but may include eczema, dermographism, mucosal ulcers, angioedema, vasculitis, erythroderma, and erythema annulare centrifugum. Pruritus in CEL is thought to result from eosinophil degranulation, releasing inflammatory mediators suchas histamine and leukotrienes that stimulate skin nerve endings. Prolonged activation may lead to chronic pruritus and tissue irritation, as seen in this case. Currently, there is no standardized CEL treatment protocol nor guidelines for initiating therapy in asymptomatic patients. Some experts recommend treatmentwhen eosinophil counts exceed 1.5–2 x 109/L. Treatment goals include reducing eosinophil levels, limiting tissue infiltration, and preventing further organ damage. Mainstays of treatment include steroids, hydroxyurea, and tyrosine kinase inhibitors. This case report of CEL with skin manifestations highlights that prednisone therapy is beneficial in improving the symptoms and clinical condition of patients.