Magnesium homeostasis and hypomagnesemia in children with malignancy.

Hypomagnesemia is not uncommon among children with malignancies. It is especially seen in association with certain medications and can be further complicated by the presence of diarrhea and malnutrition. Severe hypomagnesemia may cause disturbances in the neuromuscular and cardiovascular systems. All patients with hypomagnesemia should be supplemented with the mineral, and urgent treatment is indicated when serum magnesium decreases below 1.0 mg/dl, a level under which symptoms may develop. This review addresses the essentials of magnesium physiology, and pathophysiology of hypomagnesemia, its etiologies, clinical manifestations and ways to treat it, with an emphasis on the child with hematologic/oncologic disorders.