Acute Myeloid Leukemia (M4)/Myeloid Sarcoma Presenting with Hyperleukocytosis, 47,XX + mar Case

Hyperleukocytosis is defined as a blood blast count >100.000/ mm3 and may occur most commonly in monocytic (M4) acute myeloid leukemia (AML). Hyperleukocytosis is a medical emergency associated with lung and central nervous system leukostasis. An 18-month-old female patient was brought to our clinic with anemia, thrombocytopenia, and leukocytosis with bilateral palpebral swelling/proptosis, a palpable mass in the midline, and lymphadenopathy in the neck. Myeloid sarcoma was suspected. The patient had AML M4 morphological features, and 47,XX + mar was detected in bone marrow karyotype analysis. She had complications such as hyperleukocytosis, leukostasis (blurring of consciousness, tachypnea/tachycardia), tumor lysis syndrome, and disseminated intravascular coagulation. In addition to low-dose cytoreduction chemotherapy, leukocyte apheresis was performed. All symptoms and complaints of the patient disappeared. Therefore, myeloid sarcoma should be considered in young children with orbital swelling/ proptosis, an abdominal mass, high leukocyte count at diagnosis, AML M4 morphological features, and diffuse intravascular coagulation.