Hyperleukocytosis in patients with acute myeloid leukemia admitted to the intensive care unit: a single-center retrospective analysis

A relevant proportion of patients with acute myeloid leukemia (AML) presenting with hyperleukocytosis are admitted to the intensive care unit (ICU). However, data on characteristics and outcomes of these patients are limited. We therefore conducted a single-center retrospective analysis including 69 consecutive AML patients with a white blood cell (WBC) count > 100.000/µl who had been treated on the ICU between 2011 and 2020. The median age was 63 years (range: 14-87 years). Males accounted for the majority of cases (n = 43; 62.3%). Mechanical ventilation (MV), renal replacement therapy and the use of vasopressors were necessary in 34.8%, 8.7% and 40.6% of patients, respectively. Cardiopulmonary resuscitation was performed in 15.9% of patients. The ICU, hospital, 90-day and 1-year survival rates were 53.6%, 43.5%, 42% and 30.4%, respectively. Age (p = 0.002), SOFA score (p < 0.001) and MV (p < 0.001) were independently associated with a reduced survival probability. A score comprising the factors age > 70 years, lactate dehydrogenase level > 1500 U/l, WBC count > 150.000/µl, elevated lactate level and SOFA score > 7 allowed the discrimination of 3 distinct risk groups (low-risk: 0-1 points, intermediate-risk: 2 points, high-risk: 3-5 points) with regard to survival (p < 0.0001). Taken together, the present analysis indicates that more than two-thirds of AML patients with hyperleukocytosis treated on the ICU die within 1 year. However, outcomes vary considerably depending on the presence of risk factors.