Define the incidence and risk factors for intravenous iron–induced hypophosphatemia, which is primarily caused by ferric carboxymaltose
Explain the underlying pathophysiology of intravenous iron–induced hypophosphatemia and how elevations of FGF23 cause renal phosphate wasting
Recognize signs and symptoms of severe hypophosphatemia to guide appropriate management
A 23-year-old woman presents with progressive fatigue and decreased exercise tolerance. Because of suspected iron deficiency from heavy menstrual bleeding, she was previously advised to take oral iron, but gastrointestinal distress limits her adherence. Laboratory testing reveals iron deficiency anemia: hemoglobin 9.8 g/dL and ferritin 4 ng/mL. She is referred for intravenous (IV) iron and gynecologic management of heavy menstrual bleeding. Based on the infusion clinic's formulary, she receives 2 weekly doses of ferric carboxymaltose (FCM), 750 mg each. One week later, she continues to experience fatigue and weakness, and she now describes...
