Does low-calcium dialysate accelerate secondary hyperparathyroidism in continuous ambulatory peritoneal dialysis patients?
A lower-calcium dialysate has been advocated for continuous ambulatory peritoneal dialysis (CAPD) patients for the purpose of increasing oral calcium intake as a phosphate binder and decreasing the need for aluminum-containing phosphate binders and, hence, decreasing the risk of aluminum intoxication. Twelve CAPD patients were evaluated retrospectively after switching from a dialysate containing 3.5 mEq/L of calcium to a new dialysate containing 2.5 mEq/L of calcium. Patients were on the new dialysate for at least 1 year. Serum calcium, phosphate, alkaline phosphatase, aluminum, and intact or N-terminal parathyroid hormone (I-PTH, N-PTH) were measured. Calcium, phosphate, and aluminum did not change significantly. Alkaline phosphatase doubled, but was not statistically significant. I-PTH and N-PTH rose from 2.9 +/- 2.24 to 7.4 +/- 7.4 times normal (p < 0.012). Three of 7 patients who had x-ray evaluations before, during, and 1 year after change of dialysate had radiographic progression of bone disease. Three patients required a parathyroidectomy due to the development of severe secondary hyperparathyroidism. In conclusion, the indiscriminate use of dialysate containing 2.5 mEq/L of calcium, in CAPD patients, may place the patients at higher risk for progression of hyperparathyroidism.
Rotellar
C
C
Georgetown University Medical Center, Washington, D.C. 20007.
Kinsel
V
V
Goggins
M
M
Tarman
G
G
Stull
M
M
Mazzoni
M J
MJ
Mosher
W F
WF
Rakowski
T A
TA
Winchester
J F
JF
D000535:Aluminum / Q000097:blood; D001842:Bone and Bones / Q000473:pathology; D002118:Calcium / Q000032:analysis* / Q000097:blood; D015314:Dialysis Solutions / Q000009:adverse effects / Q000737:chemistry*; D005260:Female; D006801:Humans; D006962:Hyperparathyroidism, Secondary / Q000097:blood / Q000209:etiology* / Q000473:pathology; D007676:Kidney Failure, Chronic / Q000097:blood / Q000150:complications / Q000628:therapy; D008297:Male; D008875:Middle Aged; D010531:Peritoneal Dialysis, Continuous Ambulatory / Q000009:adverse effects*; D010710:Phosphates / Q000097:blood; D012189:Retrospective Studies; D012709:Serum Albumin / Q000032:analysis
D015314:Dialysis Solutions; D010710:Phosphates; D012709:Serum Albumin; D000535:Aluminum; D002118:Calcium