Tehran University of Medical Sciences Case Reports in Clinical Practice 2538-2683 2 4 2018 05 14 120 125 EN Faeze Moghimpour-Bijani Department of Internal Medicine, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran. Sahar Karimpour-Reyhan Assistant Professor, Department of Internal Medicine, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran. Mahsa Abbaszadeh Assistant Professor, Department of Internal Medicine, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran. 2017 12 25 2018 01 30 Adult T-cell leukemia (ATL) is the only T-cell lymphoproliferative disease, known to be caused by a virus. While human T-lymphotropic virus type 1 (HTLV-1) is found to cause adult T-cell leukemia, other T-cell neoplastic diseases do not correlate with human T-lymphotropic virus type 1. Adult T-cell leukemia usually demonstrates an aggressive course and poor prognosis. Human T-lymphotropic virus type 1 is transmitted via breast feeding, sexual contact, shared needles, and infected blood products. Moreover, some geographic areas are depicted to be endemic for human T-lymphotropic virus type 1; northeast of Iran is known to be one. Here in, a case of adult T-cell leukemia is discussed who presented by hypercalcemia and paraparesia. Hepatosplenomegaly was detected in physical examination and abdominal sonography revealed multiple paraaortic lymphadenopathy. Whole body bone scan demonstrated multiple hot points in skeleton. Chest computed tomography (CT) scan revealed leukemic infiltrations of both lungs. The leukocyte count of peripheral blood was 34000-50000 per mm3, and excessive amounts of mature lymphocytes were observed in peripheral smear. Flow cytometry of bone marrow aspiration reported adult T-cell leukemia. The titer of human T-lymphotropic virus type 1 antibody was elevated in enzyme-linked immunosorbent assay (ELISA) method. Despite the patient was originated from a non-endemic origin, all members of his family including his spouse and children found to be positive for human T-lymphotropic virus type 1. This manuscript describes the clinical course and diagnosis of a patient with adult T-cell leukemia, and clinical suspicions during the course of the disease. https://crcp.tums.ac.ir/index.php/crcp/article/view/167 https://crcp.tums.ac.ir/index.php/crcp/article/download/167/95