Can low-calcium peritoneal dialysis solution safely replace the standard calcium solution in the majority of chronic peritoneal dialysis patients?
OBJECTIVE
To evaluate the use of low-calcium solution as the standard solution in chronic peritoneal dialysis patients.


METHODS
Prospective long-term follow-up study over a one-year period.


METHODS
University hospital.


METHODS
The change of the calcium concentration of the dialysate from 1.75 mmol/L to 1.25 mmol/L.


METHODS
Serum calcium and phosphorus concentration and intact parathyroid hormone (iPTH).


METHODS
Fifty normo- and hypercalcemic patients using the standard 1.75 mmol/L calcium solution.


RESULTS
Serum ionized calcium (iCa) decreased significantly during the first six months, resulting in a significant increment of iPTH (baseline value: 0.9-79, median 9.4 pmol/L; at six months: 1.1-111, median 20.6 pmol/L; p < 0.05). In 28 patients completing the study, iPTH remained significantly elevated, despite high normal iCa. At similar changes of iCa, patients with baseline iPTH > 20 pmol/L showed a significantly higher increase in iPTH than patients with low iPTH (24.0 vs 5.0; p < 0.01), despite a more than doubled dose of alfacalcidol and calcium carbonate (mean dose of 1580 increased to 3277 mg/day). During the follow-up, 21 episodes of hypercalcemia were observed. Phosphorus control was adequate.


CONCLUSIONS
Low-calcium solution cannot be used as a standard solution, especially in patients with iPTH levels indicating mild or severe hyperparathyroidism, because in these patients iPTH may rise further.
Buijsen
C G
CG
Department of Medicine, Academic Medical Center, Amsterdam, The Netherlands.
Struijk
D G
DG
Huijgen
H J
HJ
Boeschoten
E W
EW
Wilmink
J M
JM
D000328:Adult; D000368:Aged; D002118:Calcium / Q000008:administration & dosage* / Q000032:analysis / Q000097:blood; D002119:Calcium Carbonate / Q000008:administration & dosage / Q000627:therapeutic use; D015314:Dialysis Solutions / Q000008:administration & dosage* / Q000032:analysis; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006887:Hydroxycholecalciferols / Q000008:administration & dosage / Q000627:therapeutic use; D006934:Hypercalcemia / Q000097:blood / Q000209:etiology; D006962:Hyperparathyroidism, Secondary / Q000097:blood / Q000209:etiology; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood; D010530:Peritoneal Dialysis; D010758:Phosphorus / Q000097:blood; D011446:Prospective Studies; D016896:Treatment Outcome
D015314:Dialysis Solutions; D006887:Hydroxycholecalciferols; D010281:Parathyroid Hormone; D010758:Phosphorus; D002119:Calcium Carbonate; D002118:Calcium; C008088:alfacalcidol