Abstract Background Hyperleukocytosis in acute leukemia can lead to many complications including but not limited to leukostasis, disseminated intravascular coagulation (DIC), and pseudohypoxemia. Treatment of these tenuous patients is often complicated and requires a multidisciplinary approach. Case Presentation A 58-year-old male with a history of anemia and tobacco use presented with weakness, abdominal pain, and pancytopenia to an outside hospital. Initial labs showed WBC 201,000/µL, hemoglobin 9.2 g/dL, and platelets 17 × 109/L. He was transferred for higher level of care; however, he rapidly declined within hours of arrival in the setting of hypoxia, hypotension, and melena. Repeat labs revealed WBC 322,000/µL, normal fibrinogen, hemoglobin of 5.5, and a peripheral smear with 87% blasts, concerning for acute myeloid leukemia (AML). He was started on hydroxyurea with initiaiton of leukapharesis prior to repeat complete blood count resulting; however, this was terminated early due to development of DIC as evidenced by decreasing hemoglobin and fibrinogen levels as well as increased prothrombin time and D-dimer. Ultimately, patient’s mentation worsened and required intubation. Post-intubation arterial blood gas revealed significantly low partial pressure of oxygen (PaO2), which was wildly discordant from his normal pulse oximetry. The patient progressed to multiorgan failure within hours and expired shortly thereafter. Bone marrow aspirate later confirmed AML with morphology consistent with acute promyelocytic leukemia (APML). Discussion This case highlights the diagnostic and therapeutic challenges of managing hyperleukocytosis in APML. APML carries a high risk of DIC, traditionally making leukapheresis contraindicated, though recent studies suggest possible benefit. Standard of care recommends leukapheresis for symptomatic leukostasis, which can manifest as confusion, dyspnea and/or mesenteric ischemia. However, our patient had multiple contraindications, including DIC and GI bleeding. Balancing the risks and benefits of leukapheresis in such patients is difficult—transfusions may be necessary for DIC and GI bleeding but can worsen leukostasis. In our case, leukapheresis was initiated before DIC and GI bleeding were recognized due to the patient’s acuity; in retrospect, transfusions without leukapheresis may have been preferred with plan for systemic therapy. Furthermore, this case illustrates a rare phenomenon of pseudohypoxemia—spuriously low PaO2 due to leukocyte oxygen consumption; awareness of which can prevent unnecessary intubation. Recognition of pseudohypoxemia and leukapheresis contraindications is essential for intensivists managing critically ill patients with acute leukemia. This further highlights the need for multidisciplinary approach. This abstract is funded by: None
Patel et al. (Fri,) studied this question.