Differentiation syndrome in acute myeloid leukemia after treatment with azacitidine

We report a case report of hyperleukocytosis, fever, hypotension, pulmonary and pericardial effusions, and acute kidney injury during initial treatment with azacitidine in a patient with AML-MRC. Collectively, the symptomatology resembled differentiation syndrome. Azacitidine has been previously associated with fever, peripheral edema, and hyperleukocytosis, but its side effect profile has never been described as similar to differentiation syndrome. The patient's deteriorating course quickly turned around after treatment with dexamethasone. This potential reaction, and potential treatment, is important for clinicians to be aware of.