Calcium concentration in the CAPD dialysate: what is optimal and is there a need to individualize?
OBJECTIVE
To evaluate risk/benefit of various continuous ambulatory peritoneal dialysis (CAPD) dialysate calcium concentrations.


METHODS
A review of the literature on the effects of various CAPD dialysate Ca concentrations on plasma Ca, plasma phosphate, plasma parathyroid hormone (PTH), doses of calcium carbonate, doses of vitamin D analogs, and requirements of aluminum-containing phosphate binders.


METHODS
Eleven studies of nonselected CAPD patients, and 13 studies of CAPD patients with hypercalcemia were reviewed.


RESULTS
In nonselected CAPD patients, treatment with a reduced dialysate Ca concentration (1.00, 1.25, or 1.35 mmol/L) improved the tolerance to calcium carbonate and/or vitamin D metabolites and reduced the need for Al-containing phosphate binders. When using dialysate Ca 1.25 or 1.35 mmol/L, the initial decrease of plasma Ca and increase of PTH could easily be reversed with an immediate adjustment of the treatment. After 3 months, stable plasma Ca and PTH levels could be maintained using only monthly investigations. In patients with hypercalcemia and elevated PTH levels, treatment with dialysate Ca concentrations below 1.25 mmol/L implied a considerable risk for the progression of secondary hyperparathyroidism. When hypercalcemia was present in combination with suppressed PTH levels, a controlled increase of PTH could be obtained with a temporary discontinuation of vitamin D and/or a reduction of calcium carbonate treatment in combination with a dialysate Ca concentration of 1.25 or 1.35 mmol/L.


CONCLUSIONS
Most CAPD patients can be treated effectively and safely with a reduced dialysate Ca concentration of 1.35 or 1.25 mmol/L. Treatment with dialysate Ca concentrations below 1.25 mmol/L should not be used. A small fraction of patients with persistent hypocalcemia need treatment with high dialysate Ca, such as 1.75 mmol/L.
Bro
S
S
Nephrology Department P, Rigshospitalet, University of Copenhagen, Denmark.
Brandi
L
L
Daugaard
H
H
Olgaard
K
K
D002118:Calcium / Q000032:analysis* / Q000097:blood; D015314:Dialysis Solutions; D006801:Humans; D006934:Hypercalcemia / Q000628:therapy*; D006996:Hypocalcemia / Q000628:therapy; D010281:Parathyroid Hormone / Q000378:metabolism; D018579:Patient Selection; D010531:Peritoneal Dialysis, Continuous Ambulatory; D018570:Risk Assessment
D015314:Dialysis Solutions; D010281:Parathyroid Hormone; D002118:Calcium