Special Clinical Scenarios: Hyperleukocytosis

Abstract

Acute myeloid leukemia (AML) presenting with hyperleukocytosis portends a poor diagnosis. Whether hyperleukocytosis is a sign of an inherently prognostically poor leukemia or an independent risk factor has been discussed controversially. Hyperleukocytosis indicates high tumor burden, hence tumor lysis syndrome, coagulopathy, and electrolyte disbalance are associated with the diagnosis, whether from spontaneous tumor cell disintegration or cell death from cytoreductive chemotherapy. Leukostasis is a frequent complication of hyperleukocytosis, constituting a medical emergency; prime target organs are heart, lung, kidney, and brain. Leukostasis is addressed with hyperhydration, alkalinization, anti-uremics, steroids, and sometimes leukodepletion by apheresis, but none of the measures should delay initiation of induction therapy.