Torsade de pointes and elevated magnesium and calcium requirements associated with intravenous pentamidine

We present a report of markedly elevated calcium and magnesium requirements in an AIDS patient receiving central venous nutrition. These increased requirements were attributed to urinary magnesium losses associated with intravenous pentamidine therapy. The combination of intravenous pentamidine and electrolyte abnormalities resulted in the development of the dysrhythmia, torsade de pointes, in the patient. A review of literature presenting similar cases is included. Nutrition practitioners should be aware of the often prolonged effect of intravenous pentamidine on magnesium and calcium homeostasis so that adequate supplementation will be provided, perhaps preventing the development of life-threatening torsade de pointes.