Metabolic Emergencies in the Child With Acute Leukemia

Acute leukemia is the most common malignancy in children. Children with acute lymphoblastic leukemia and acute myeloid leukemia are frequently diagnosed, evaluated, and treated in emergency departments. Children with acute leukemia may develop multiple life-threatening electrolyte abnormalities, either at the time of diagnosis or after initiation of therapy. Children with acute lymphoblastic leukemia or hyperleukocytosis are at high risk for developing tumor lysis syndrome, which includes hyperuricemia, hyperkalemia, hyperphosphatemia, or hypocalcemia. Clinical complications of tumor lysis syndrome include renal insufficiency or acute renal failure, seizures, altered mental status or coma, cardiac arrhythmias, and sudden death. Rarely, children with acute leukemia will present with hypercalcemia. After initiation of systemic chemotherapy, some children will develop hyponatremia due to excessive hydration, dehydration, or syndrome of inappropriate antidiuretic hormone. Prompt recognition and prevention or treatment of metabolic abnormalities by the treating physician is crucial to preventing end-organ damage or death.