Leukostasis

Leukostasis (also called symptomatic hyperleukocytosis) is a medical emergency most commonly seen in patients with acute myeloid leukemia. It is characterized by an extremely elevated blast cell count and symptoms of decreased tissue perfusion. The pathophysiology of leukostasis is not well understood, but inadequate delivery of oxygen to the body's cells is the result. Leukostasis is diagnosed when white cell plugs are seen in the microvasculature. The most common symptoms are dyspnea and hypoxia, usually accompanied by visual changes, headaches, dizziness, confusion, somnolence, and coma. Prompt treatment is required since, if left untreated, it has a very high mortality rate. Treatments aim to rapidly reduce white blood cell counts while also treating the underlying disorder.