RESUMO
PURPOSE: Ophthalmic disease may rarely be a presenting feature of chronic myeloid leukemia (CML). METHODS: We report a case of a 53-year-old man with type 1 diabetes mellitus who presented with a rapid onset of bilateral blurred vision. RESULTS: He was noted to have bilateral macular edema and was initially treated for presumed diabetic macular edema (DME) with intravitreal alifbercept injections. One month later, there was complete resolution of his macular edema. Review of his history and imaging revealed features atypical for DME, specifically; the rapid onset of bilateral blurred vision over 2-3 weeks, numerous cotton wool spots within the macula, the absence of any exudates, the symmetrical macular edema with a "vaulted ceiling" appearance (more typical of cystoid macular edema) and the dramatic response to a single intravitreal aflibercept injection. One week after his intravitreal injection, the patient was diagnosed with CML following marked leucocytosis on a routine blood test by his general practitioner. Although uncommon, sudden onset bilateral edema in the absence of other chronic diabetic changes should prompt consideration of an underlying haematological cause. CONCLUSION: This case highlights the importance of considering CML as a differential diagnosis in patients presenting with sudden onset, bilateral cystoid macular oedema. Vigilance is especially important in patients with co-existing diabetic retinopathy as the clinical features of leukemic retinopathy can overlap. Furthermore, the diagnosis of CML in a patient with diabetes mellitus should prompt extra observation for accelerated worsening of diabetic retinopathy.