Low- and high-turnover bone disease in continuous ambulatory peritoneal dialysis: effects of low-Ca2+ peritoneal dialysis solution.
Calcium carbonate (CaCO3) is an effective phosphate (PO4) binder in uremics, and its use reduces aluminum (Al) intake. By maintaining high serum Ca2+, it decreases serum parathyroid hormone (PTH) levels. Hypercalcemia, however, often limits the dosage. In order to evaluate the effects of a low-Ca peritoneal dialysis solution (PDS) (1.25 mmol/L) on Ca metabolism, we studied the following in 12 continuous ambulatory peritoneal dialysis (CAPD) patients with hypercalcemia (6 with low PTH levels, low-turnover bone disease, group 1, and 6 with high PTH levels, high-turnover bone disease, group 2, documented by bone biopsies): serum Ca2+; serum PTH; bone morphology. The follow-up was 12 months. Results show that in both groups within the third month there was a decrease in serum Ca2+. In group 1 serum PTH increased, reaching the norm, and in group 2 it further increased exceeding the norm. Because in both groups serum Ca2+ was normal, it was possible to increase oral CaCO3 (10.5 +/- 2.5 g/day) to control PO4 levels and to stop Al gels. In group 2, in order to avoid the further rise of serum PTH, the low-Ca PDS was supplemented with 2 micrograms/day of 1,25(OH)2D3 (vitamin D3); this was followed by a reduction in serum PTH with no increase in Ca2+ and PO4. The use of low-Ca PDS may be useful in preventing hypercalcemia in CAPD patients treated with high oral doses of CaCO3 and in improving low-turnover bone disease, while low-Ca PDS supplemented with vitamin D3 improves high-turnover bone disease.
Nephrology and Dialysis Unit, St. Paul's Hospital, Savona, Italy.
S
S
Carozzi
M G
MG
Nasini
O
O
Santoni
A
A
Pietrucci
D000284:Administration, Oral; D000535:Aluminum / Q000097:blood; D002118:Calcium / Q000032:analysis* / Q000097:blood; D002119:Calcium Carbonate / Q000008:administration & dosage; D012080:Chronic Kidney Disease-Mineral and Bone Disorder / Q000097:blood*; D015314:Dialysis Solutions / Q000737:chemistry*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood; D010531:Peritoneal Dialysis, Continuous Ambulatory / Q000379:methods; D010710:Phosphates / Q000097:blood; D012189:Retrospective Studies
D015314:Dialysis Solutions; D010281:Parathyroid Hormone; D010710:Phosphates; D000535:Aluminum; D002119:Calcium Carbonate; D002118:Calcium