Early postkidney transplantation hypophosphatemia.

Area of Science:

• Nephrology
• Transplantation Medicine
• Endocrinology

Background:

• Hypophosphatemia is a frequent complication following kidney transplantation (Tx).
• This condition is multifactorial and can impact patient outcomes.
• Understanding its early incidence and risk factors is critical for management.

Purpose of the Study:

• To determine the frequency of hypophosphatemia in the early period after kidney Tx.
• To identify risk factors associated with post-Tx hypophosphatemia.

Main Methods:

• Serum phosphate (Pi), creatinine (Cr), 25-hydroxyvitamin D (25[OH]D), intact parathyroid hormone (iPTH), and fibroblast growth factor 23 (FGF-23) were measured in 50 renal transplant recipients.
• 24-hour urinary excretion of Pi and Cr, estimated glomerular filtration rate (eGFR), and the ratio of phosphate transport maximum to eGFR (TMP/GFR) were assessed.
• Measurements were taken before Tx and on days +10 and +30 post-Tx.

Main Results:

• Hypophosphatemia was observed in 40% and 42% of patients on day +10 and +30 post-Tx, respectively.
• Pre-Tx FGF-23 levels were significantly higher in patients who developed hypophosphatemia.
• Multivariate analysis indicated that pre-Tx FGF-23, post-Tx FGF-23, post-Tx Cr, and TMP/GFR were significant predictors of post-Tx hypophosphatemia.

Conclusions:

• Fibroblast growth factor 23 (FGF-23) plays a significant role in the development of post-kidney Tx hypophosphatemia.
• Impaired phosphate handling, indicated by TMP/GFR and creatinine levels, also contributes to this complication.
• These findings highlight key factors for monitoring and managing hypophosphatemia in kidney transplant recipients.