Evidence Hub

Symptomatic severe hypophosphatemia after intravenous ferric carboxymaltose

Fang W, McMahon LP, Bloom S, Garg M

JGH open : an open access journal of gastroenterology and hepatology, 2019

Abstract

Intravenous iron is commonly prescribed for treatment of iron deficiency, with modern formulations demonstrating an acceptable safety profile in the majority of patients. We report the case of a patient who was hospitalised with muscle pain, deteriorating mobility and multiple fractures following repeated ferric carboxymaltose infusions. Investigations revealed severe hypophosphatemia with serum phosphate of 0.27 mmol/L, 25-hydroxyvitamin D (25OHD) level of 32 nmol/L and insufficiency fractures of the sacrum and L5 transverse process. The patient's hypophosphatemia was corrected with several infusions of intravenous phosphate, as well as oral phosphate and calcitriol, with subsequent resolution of her muscle aches, back pain and immobility. The risk of persistent hypophosphatemia and osteomalacia may be higher with iron carboxymaltose than other iron formulations and a transient increase in intact fibroblast growth factor-23 with reduced renal tubular phosphate absorption has been postulated as the key mechanism. This risk appears increased by repeated iron infusions, underlying malnutrition, hypophosphatemia at baseline, vitamin D deficiency, hyperparathyroidism or anti-resorptive medication use. The true risk and incidence of hypophosphatemia need to be clarified so that appropriate monitoring, prevention and treatment strategies can be developed.

How strong is the evidence?

Evidence Hub reads this as a case report, done in people. Its evidence level is 5 of 5 (Very low · case / narrative / animal / in vitro / in silico). Case reports, narrative reviews, and animal, cell or computer-model studies give the weakest evidence for human health.

How the five levels of evidence work. The level is assigned automatically from the abstract and can be wrong, so check the paper.

Read the paper

Related studies

Go deeper in Evidence Hub

Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.

Open this study Sign up free