Hypophosphatemia After Ferric Carboxymaltose Therapy

Öz

Aim: Hypophosphatemia is a recognized adverse effect of ferric carboxymaltose (FCM) therapy; however, data from routine clinical practice remain limited. This study aimed to determine the frequency of hypophosphatemia following FCM treatment and to identify clinical and biochemical factors associated with post-treatment serum phosphate levels. Material and Method: This retrospective study included 54 adult patients who received FCM for the treatment of iron deficiency and had available serum phosphate measurements before and after treatment. Demographic characteristics, laboratory parameters, intravenous iron dose, and comorbid conditions were evaluated. Factors associated with post-treatment serum phosphate levels were assessed using univariate and multivariable linear regression analyses. Findings: The mean age was 48.85±17.96 years, and 72.2% of the patients were female. Hypophosphatemia developed in 25 patients (46.3%), including 8 (14.8%) with mild and 17 (31.5%) with moderate hypophosphatemia; no cases of severe hypophosphatemia were observed. In univariate analysis, baseline serum phosphate level was significantly associated with post-treatment serum phosphate level (β=0.501, 95% CI: 0.100–0.902; p=0.015). This association remained significant in multivariable analysis (β=0.553, 95% CI: 0.056–1.049; p=0.030). No significant associations were identified between post-treatment phosphate levels and age, sex, creatinine, ferritin, hemoglobin, intravenous iron dose, or accompanying comorbidities. Conclusion: Hypophosphatemia is a common finding following FCM treatment, although most cases are mild to moderate in severity. Lower baseline serum phosphate level appears to be independently associated with lower post-treatment phosphate levels. Monitoring serum phosphate after FCM administration may be beneficial, particularly in patients with low baseline phosphate levels.

Anahtar Kelimeler

• Ferric Carboxymaltose
• Intravenous Iron Therapy
• Iron Deficiency Anemia
• Phosphate Metabolism
• Hypophosphatemia

Destekleyen Kurum

None

Etik Beyan

This study was approved by the Samsun University Non-Interventional Clinical Research Ethics Committee (Decision No: GOKAEK 2026/1/3, Date: 11 February 2026). The study was conducted in accordance with the principles of the Declaration of Helsinki.

Teşekkür

None

Ferrik Karboksimaltoz Tedavisi Sonrası Hipofosfatemi

Öz

Amaç: Ferrik karboksimaltoz (FCM) tedavisi sonrası gelişen hipofosfatemi önemli bir yan etki olarak kabul edilmekle birlikte, rutin klinik uygulamaya ilişkin veriler sınırlıdır. Bu çalışmada, FCM tedavisi sonrasında gelişen hipofosfatemi sıklığının belirlenmesi ve tedavi sonrası serum fosfat düzeyleri ile ilişkili klinik ve biyokimyasal faktörlerin değerlendirilmesi amaçlandı. Gereç ve Yöntem: Bu retrospektif çalışmaya, demir eksikliği nedeniyle FCM tedavisi alan ve tedavi öncesi ile tedavi sonrası serum fosfat ölçümleri bulunan 54 erişkin hasta dahil edildi. Hastaların demografik özellikleri, laboratuvar parametreleri, uygulanan intravenöz demir dozu ve eşlik eden komorbiditeleri değerlendirildi. Tedavi sonrası serum fosfat düzeyleri ile ilişkili faktörler tek değişkenli ve çok değişkenli doğrusal regresyon analizleri kullanılarak incelendi. Bulgular: Hastaların yaş ortalaması 48,85±17,96 yıl olup, %72,2'si kadındı. Tedavi sonrasında 25 hastada (%46,3) hipofosfatemi gelişti. Bunların 8'i (%14,8) hafif, 17'si (%31,5) orta derecede hipofosfatemi olup, ağır hipofosfatemi saptanmadı. Tek değişkenli analizde başlangıç serum fosfat düzeyinin tedavi sonrası serum fosfat düzeyi ile anlamlı ilişkili olduğu belirlendi (β=0,501; %95 GA: 0,100–0,902; p=0,015). Bu ilişki çok değişkenli analizde de anlamlılığını korudu (β=0,553; %95 GA: 0,056–1,049; p=0,030). Tedavi sonrası serum fosfat düzeyleri ile yaş, cinsiyet, kreatinin, ferritin, hemoglobin, intravenöz demir dozu ve eşlik eden komorbiditeler arasında anlamlı ilişki saptanmadı. Sonuç FCM tedavisi sonrasında hipofosfatemi sık görülmekte olup, olguların büyük çoğunluğu hafif ve orta şiddettedir. Düşük başlangıç serum fosfat düzeyi, tedavi sonrası düşük serum fosfat düzeyleri ile bağımsız olarak ilişkilidir. Özellikle başlangıç fosfat düzeyi düşük hastalarda, FCM tedavisi sonrasında serum fosfat düzeylerinin izlenmesi yararlı olabilir.

Anahtar Kelimeler

• Ferrik karboksimaltoz
• İntravenöz demir tedavisi
• Demir eksikliği anemisi
• Fosfat metabolizması
• Hipofosfatemi

Destekleyen Kurum

Yoktur

Etik Beyan

Bu çalışma için Samsun Üniversitesi Girişimsel Olmayan Klinik Araştırmalar Etik Kurulu'ndan onay alınmıştır (Karar No: GOKAEK 2026/1/3, Tarih: 11.02.2026). Çalışma Helsinki Deklarasyonu ilkelerine uygun olarak yürütülmüştür.

Teşekkür

Yoktur

Kaynakça

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