A Case of Chronic Myeloid Leukemia Presenting as Bilateral Retinopathy.

Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm with raised granulocyte cell line. It arises in the hematopoietic stem cell and is characterized by the presence of BCR-ABL fusion gene as a result of translocation between chromosomes t(9,22) (q34; q11.2). CML affects bone marrow and peripheral blood. CML can be asymptomatic and is usually discovered on routine blood investigations. It can also present as symptoms associated with anemia and splenomegaly. Rarely do CML patients present with retinal abnormalities as an initial presentation. We cover a case of CML in this report that had retinal involvement as one of its earliest manifestations. Patient presented with gradual loss of vision in both eyes. Multiple bilateral intraretinal and preretinal hemorrhages with exudates were found during fundus examination. Blood tests revealed a raised leukocyte count along with lower hemoglobin levels. Peripheral smear revealed 4% blast cells. Bone marrow aspiration showed hypercellular marrow, marked granulocyte proliferation, and raised myeloid erythroid ratio. The diagnosis was further confirmed by fluorescence in-situ hybridization (FISH) which showed BCR-ABL1 fusion gene. Patient was immediately started on chemotherapy and has been on follow-up since then. Visual acuity of the patient improved and there was no progression of retinopathy. This case thus serves as an illustration of how early detection and management can significantly slow the progression of retinopathy and improve visual outcomes.