Dr.Mohammad Shaikhani.

CABM/FRCP

HyperphosphataemiaHyperphosphataemia

Amann K, Gross ML, London GM, Ritz E:Hyperphosphatemia - a silent killer of patients with uremia.

NDT , 1999,14,2085-2087.

Metastatic Calcification & Metastatic Calcification & OssificationOssification

Amorphous(CaMg)3(PO4)2

Soft tissue Heart Lungs Kidneys

HydroxyapatiteCa10(PO4)6(OH)2

Vascular Valvular Joints Ocular

Calcium and phosphate are deposited in one of two forms;Calcium and phosphate are deposited in one of two forms;

CALCIUM

• Evaluation Monthly • • Daily intake should not be > 2000 mg/day (eg 1500

from P-binders & 500 from diet ) • Target: Low normal preferred : 2.1 – 2.4 mmol/L

(corrected (8.4 – 9.5 mg/dl) • If > 2.55 mol/L(10.2mg/dl), change to Non-Ca binders,

↓ Vit D or change to low Ca-dialysate

PHOSPHORUS

• Evaluation Monthly

• Daily intake (adjusted to protein intake) 800 – 1000mg/day

• Phosphate/ gram of protein : 12 – 16 mg.

• Target 1.13 - 1.78 mmol/L

(3.5 – 5.5 mg/dl)

PHOSPHATE BINDERS

Start when P or PTH > Target Use CaCO3 or/and non-Ca binder(Sevelamer

Limit Ca intake from binders to 1500mg/day.

1.CaCO3 upto 600 mg BD with food 2.Sevelamer (Renagel) 800 mg with meals(↑upto 2 tab TID

• Stop Ca-binder if Ca >2.55 mmol/L or PTH < 15• Aluminum binder may be used for short term (up to 4 wks) if P >2.33 ( 7.0 mg/dl), &for one course. In such pt, consider more frequent dialysis.

PHOSPHATE BINDERS

Start when P or PTH > Target Use CaCO3 or/and non-Ca binder(Sevelamer

Limit Ca intake from binders to 1500mg/day.

1.CaCO3 upto 600 mg BD with food 2.Sevelamer (Renagel) 800 mg with meals(↑upto 2 tab TID

• Stop Ca-binder if Ca >2.55 mmol/L or PTH < 15• Aluminum binder may be used for short term (up to 4 wks) if P >2.33 ( 7.0 mg/dl), &for one course. In such pt, consider more frequent dialysis.

Vitamin D (Calcitriol)

Start if PTH > 33 pmol/L ( 300 pg/ml)

Ca < 2.4 mmol/l ( 6.5 mg/dl)

P < 1.8 mmol/l ( 5.5 mg/dl)

Ca x P < 4.4 ( 55 mg/dl²)

Hold Calcitriol:when PTH < 15 pmol/L(150 pglml)

Ca > 2.55 mmol/L (10.2 mg/dl)

P > 1.8 mmol/L (1.8 pg/dl)

iPTH

• PTH Target 16 – 33 pmol/L

(150-300 pg/ml)

• Evaluation Every 3 Months

When to change the dose of Calcitriol

• If decrease in PTH is > 50% after 4 wks of initiation, then decrease dose to half.

• If Calcitriol was held as PTH had decreased to < 16, restart at half the dose when PTH > 33

• High affinity for binding phosphorous High affinity for binding phosphorous - low dose required- low dose required

• Rapid phosphate bindingRapid phosphate binding

• Low solubilityLow solubility

• Low systemic absorptionLow systemic absorption (preferably none) (preferably none)

• Non toxicNon toxic

• Solid oral dose formSolid oral dose form

• Palatable - encourages compliancePalatable - encourages compliance

Characteristics of an IdealCharacteristics of an IdealOral Phosphate BinderOral Phosphate Binder

• magnesium iron hydroxycarbonate (fermagate): 1 g given 3 times a day before meals reduces serum phosphate, but dose (6 g/ day) was associated with adverse GIT events.

• MCI-196 (colestilan), a novel nonmetallic anion-exchange resin (similar to sevelamer), was associated with reductions in phosphate of 0.2 mmol per liter.

• Niacin/nicotinamide,associated with a significant reduction in serum phosphate levels, through direct inhibition of the sodium-dependent phosphate cotransporter Na-Pi-2b in GIT.

• MCI-96, niacin, and nicotinamide also lower serum cholesterol & triglyceride-rich lipoproteins.