[Native vitamin D in dialysis patients]

Area of Science:

• Nephrology
• Endocrinology
• Bone Metabolism

Background:

• Chronic kidney disease (CKD) frequently causes mineral and bone disorders, increasing patient morbidity and mortality.
• Vitamin D, essential for bone health, undergoes activation through liver and kidney hydroxylation.
• CKD, particularly end-stage renal disease (ESRD), impairs vitamin D activity due to factors like increased phosphate and decreased 1α-hydroxylase activity.

Purpose of the Study:

• To review vitamin D metabolism and physiology in the context of CKD.
• To discuss the treatment strategies for vitamin D deficiency in ESRD patients.
• To highlight the benefits of native vitamin D in managing ESRD-related complications.

Main Methods:

• Literature review of vitamin D metabolism, physiology, and treatment in CKD.
• Analysis of factors affecting vitamin D activity in ESRD.
• Evaluation of current recommendations for vitamin D supplementation in ESRD.

Main Results:

• Native vitamin D requires sequential hydroxylation for activation, with the kidney playing a crucial role.
• ESRD is associated with reduced vitamin D efficacy due to altered phosphate levels, FGF-23 secretion, and 1α-hydroxylase activity.
• Vitamin D deficiency is prevalent in ESRD, with levels below 30 ng/mL necessitating supplementation.

Conclusions:

• Native vitamin D supplementation is beneficial for ESRD patients to correct deficiency and prevent/treat hyperparathyroidism.
• Current guidelines recommend monitoring and supplementing 25-hydroxy-vitamin D, while 1.25-hydroxy-vitamin D monitoring is not routine.
• Understanding vitamin D's role is critical for managing CKD-associated mineral and bone disorders.