RESUMO
Dasatinib is a kinase inhibitor indicated for the treatment of newly diagnosed adults with Philadelphia chromosome-positive (Ph+) chronic myeloid leukemia (CML) in chronic phase and accelerated (myeloid or lymphoid blast) phase, and CML with resistance or intolerance to prior therapy including imatinib and in adults with Ph+ acute lymphoblastic leukemia1 The most common adverse reactions (≥15%) in patients with newly diagnosed chronic-phase (CP) CML include myelosuppression, fluid retention, and diarrhea, whereas in patients with resistance or intolerance to prior imatinib therapy, side effects include myelosuppression, fluid retention, diarrhea, headache, dyspnea, skin rash, fatigue, nausea, and hemorrhage. We report a 39-year-old Ethiopian female patient who received dasatinib as upfront therapy for the treatment of CP-CML who experienced chronic diarrhea for two months, which progressed to hemorrhagic colitis due to cytomegalovirus (CMV) infection of the colon. To our knowledge, this is the first case of CMV colitis in a patient receiving dasatinib as upfront therapy.
RESUMO
Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm characterized by the presence of the Philadelphia (Ph) chromosome resulting from the reciprocal translocation t(9;22)(q34;q11). The molecular consequence of this translocation is the generation of the BCR-ABL fusion gene, which encodes a constitutively active protein tyrosine kinase. The oncogenic protein tyrosine kinase, which is located in the cytoplasm, is responsible for the leukemia phenotype through the constitutive activation of multiple signaling pathways involved in the cell cycle and in adhesion and apoptosis. Avascular necrosis of the femoral head (AVNFH) is not a specific disease. It occurs as a complication or secondary to various causes. These conditions probably lead to impaired blood supply to the femoral head. The diagnosis of AVNFH is based on clinical findings and is supported by specific radiological manifestations. We reported a case of a 34-year-old Sudanese female with CML who developed AVNFH after receiving dasatinib as a second-line therapy. Though the mechanism by which dasatinib can cause avascular necrosis (AVN) is not clear, it can be postulated because of microcirculatory obstruction of the femoral head. To the best of our knowledge and after extensive literature search, this is the first reported case of AVNFH induced by dasatinib in a patient with CML.