Leukostasis and hyperleukocytosis

Background

• Pathologic diagnosis where WBC plugs seen in microvasculature
• High blast cell counts, blood viscosity is increased
• Blood flow is slowed by aggregates of tumor cells, and the primitive leukemic cells are capable of invading through endothelium and causing hemorrhage
• Usually seen in pts with AML, not seen in CML or CLL
• WBC count usu >100k, can happen as low as 50K
• Brain and lung are most commonly affected

Clinical Features

• Brain Leukostasis
  • headache
  • stupor
  • dizziness
  • tinnitus
  • visual disturbances
  • ataxia
  • confusion
  • coma
  • sudden death

• Pulmonary Leukostasis
  • respiratory distress
  • hypoxemia
  • respiratory failure

Diagnosis

• High degree of suspicion to make diagnosis
• WBC count usu >100k, can happen as low as 50K + symptoms from tissue hypoxia
• CXR usu show interstial or alveolar infiltrates

Treatment

• IV hydration to prevent dehydration that can worsen condition
• Avoid unnecessary transfusions
• Induction Chemo best treatment, improves survival
• Leukapheresis and Hydroxyurea can be use for cytoreduction while chemo being set up

Disposition

• Admit to ICU

Source

Harrison's Internal Medicine Oncologic Emergencies & Uptodate