CENTRAL ASIAN JOURNAL OF NEPHROLOGY
Case Report
Apr 09, 2026 8 5

Beyond Iron Repletion: The Hypophosphatemia Risk of Ferric Carboxymaltose

Farah Alabbasi 1 * ,
Mohammad Elraggal 2,
Raed Alenezi 3,
Ali Alshaqaq 2
1 Medicine Department, Johns Hopkins Aramco Healthcare, Dhahran, Saudi Arabia2 Nephrology Department, Specialty Medicine, Johns Hopkins Aramco Healthcare, Dhahran, Saudi Arabia 3 Endocrine Department, Specialty Medicine, Johns Hopkins Aramco Healthcare, Dhahran, Saudi Arabia* Corresponding Author
Central Asian Journal of Nephrology, 2(2), 2026, cajn014, https://doi.org/10.63946/cajn/18335
Publication date: Apr 09, 2026
Full Text (PDF)

ABSTRACT

Post-bariatric surgery patients face higher risk of micronutrient malabsorption and often receive intravenous iron like Ferric carboxymaltose (FCM).  Recent studies associate FCM with severe (serum phosphate levels < 1 mg/dL) and prolonged hypophosphatemia caused by elevated Fibroblast Growth Factor 23 (FGF23) levels, which reduces phosphate reabsorption in the kidneys via α-Klotho co-receptor. FCM, in particular, can therefore lead to notable and sustained FGF23-mediated hypophos-phatemia. We present a case of prolonged and severe hypophosphatemia secondary to fibroblast growth factor 23 (FGF23)-mediated phosphaturia following ferric carboxymaltose (FCM) administration in a post-bariatric surgery patient. This case underscores the complex interplay between intravenous iron therapy, phosphate metabolism, and altered absorption physiology following bariatric surgery. It highlights the need for clinicians to monitor phosphate levels after FCM administration, particularly in high-risk patients such as those with malabsorption.

KEYWORDS

Hypophosphatemia Fibroblast Growth Factor 23 Ferric Carboxymaltose Bariatric Surgery Nephrology Case Report

CITATION (Vancouver)

Alabbasi F, Elraggal M, Alenezi R, Alshaqaq A. Beyond Iron Repletion: The Hypophosphatemia Risk of Ferric Carboxymaltose. Central Asian Journal of Nephrology. 2026;2(2):cajn014. https://doi.org/10.63946/cajn/18335
APA
Alabbasi, F., Elraggal, M., Alenezi, R., & Alshaqaq, A. (2026). Beyond Iron Repletion: The Hypophosphatemia Risk of Ferric Carboxymaltose. Central Asian Journal of Nephrology, 2(2), cajn014. https://doi.org/10.63946/cajn/18335
Harvard
Alabbasi, F., Elraggal, M., Alenezi, R., and Alshaqaq, A. (2026). Beyond Iron Repletion: The Hypophosphatemia Risk of Ferric Carboxymaltose. Central Asian Journal of Nephrology, 2(2), cajn014. https://doi.org/10.63946/cajn/18335
AMA
Alabbasi F, Elraggal M, Alenezi R, Alshaqaq A. Beyond Iron Repletion: The Hypophosphatemia Risk of Ferric Carboxymaltose. Central Asian Journal of Nephrology. 2026;2(2), cajn014. https://doi.org/10.63946/cajn/18335
Chicago
Alabbasi, Farah, Mohammad Elraggal, Raed Alenezi, and Ali Alshaqaq. "Beyond Iron Repletion: The Hypophosphatemia Risk of Ferric Carboxymaltose". Central Asian Journal of Nephrology 2026 2 no. 2 (2026): cajn014. https://doi.org/10.63946/cajn/18335
MLA
Alabbasi, Farah et al. "Beyond Iron Repletion: The Hypophosphatemia Risk of Ferric Carboxymaltose". Central Asian Journal of Nephrology, vol. 2, no. 2, 2026, cajn014. https://doi.org/10.63946/cajn/18335

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