The article describes the clinical search for diagnosis and treatment of a patient who developed a severe ischemic stroke at a young age, when specifying the cause of which chronic myeloleucosis was identified. The unavailability of patient compliance and non-compliance with the recommended examination at the outpatient stage led to the development of severe complications. It would seem that the diagnosis of chronic myeloid leukemia, which does not represent excessive complexity, with the development of an acute condition in a young patient, such as an ischemic stroke, results in a complex diagnostic search, complicated by developing comorbidities due to general decompensation of the body.