Renal Endocrinology Moderate — endorsed by KDIGO CKD-MBD guidelines

Calcium-Phosphate Product

Calculates the calcium-phosphate product to assess risk of metastatic calcification in chronic kidney disease (CKD), particularly vascular and soft tissue calcification.

Score interpretation

Acceptable Range 0–4.4

Ca × PO₄ product < 4.4 mmol²/L²: Below threshold for increased calcification risk.

→ Continue standard CKD monitoring. Annual calcium and phosphate in CKD G3–4. More frequent in G5/dialysis.

Borderline Elevated 4.4–5

Ca × PO₄ product 4.4–5.0 mmol²/L²: Borderline — increased calcification risk.

→ Dietary phosphate restriction. Review phosphate binders. Check PTH and 25-OH vitamin D. Reduce active vitamin D if Ca elevated.

High — Elevated Calcification Risk ≥ 5

Ca × PO₄ product > 5.0 mmol²/L²: Significantly elevated. High risk of vascular and soft tissue calcification.

→ Urgent nephrology review. Phosphate binders (sevelamer preferred over calcium-based). Avoid calcium supplements. Restrict phosphate in diet. Consider cinacalcet if secondary hyperparathyroidism.

Interpretation bands for the Ca-PO₄ Product. Apply clinical judgement and local guidance.

References

Block GA, et al. Mineral metabolism, mortality, and morbidity in maintenance hemodialysis. J Am Soc Nephrol. 2004;15(8):2208–2218.
KDIGO 2017 Clinical Practice Guideline Update for the Diagnosis, Evaluation, Prevention, and Treatment of CKD-MBD.

Curated clinical cross-links plus same-class fallbacks.

Calculators

Drugs

Pathways

Decision support only — verify against a current formulary, NICE, or your local guideline before clinical use.

Score interpretation

References

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