The use of calcium carbonate to treat the hyperphosphataemia of chronic renal failure.
This study evaluates the use of calcium carbonate in chronic renal failure. Forty-eight patients (25 male, 23 female, mean age 54.3 years, six pre-dialysis. 12 CAPD, 30 haemodialysis) on phosphate restriction and requiring aluminum hydroxide (mean 2.4 +/- 0.8 g/day) to control serum phosphate, were converted to an equivalent dose of calcium carbonate (2.5 +/- 0.6 g/day). None received vitamin D analogues. Three months post-conversion there was a significant decrease in mean (+/- SEM) serum phosphate (1.86 +/- 0.08 versus 1.66 +/- 0.05 mmol/l P less than 0.01) and serum aluminum (28.3 +/- 5.4 versus 13.2 +/- 3.0 micrograms/l, P less than 0.0001): calcium/phosphate product was unchanged. Post-conversion there was an increase in serum bicarbonate, (20.6 +/- 0.5 versus 22.1 +/- 0.6 mmol/l, P less than 0.01) and serum calcium (2.32 +/- 0.02 versus 2.45 +/- 0.03 mmol/l, P less than 0.0001). No change in serum creatinine, alkaline phosphatase or parathormone occurred. No adverse effects were reported but nine (18%) patients became hypercalcaemic (2.7 to 2.93 mmol/l), eight of whom responded to dose reduction. Hypercalcaemia did not correlate with pre-conversion serum calcium, parathyroid hormone, alkaline phosphatase or aluminium. Calcium carbonate is an effective alternative to aluminium-based phosphate binders. It produces a beneficial increase in serum calcium and bicarbonate and a significant decrease in serum aluminium. Hypercalcaemia is unpredictable but is easily reversible in the majority of patients.
Williams
B
B
Department of Nephrology, Leicester General Hospital, UK.
Vennegoor
M
M
O'Nunan
T
T
Walls
J
J
D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000535:Aluminum / Q000097:blood; D001639:Bicarbonates / Q000097:blood; D002118:Calcium / Q000097:blood; D002119:Calcium Carbonate / Q000008:administration & dosage / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D010710:Phosphates / Q000097:blood*; D006435:Renal Dialysis
D001639:Bicarbonates; D010710:Phosphates; D000535:Aluminum; D002119:Calcium Carbonate; D002118:Calcium