Treatment of secondary hyperparathyroidism in hemodialyzed patients with high-dose calcium carbonate without vitamin D3 supplements.
BACKGROUND
Vitamin D compounds are usually indicated for the treatment of secondary hyperparathyroidism in dialysis patients. The possibility to induce a reversal of hyperparathyroidism with calcium supplementation alone is controversial. The present study was conducted to assess if oral calcium carbonate may constitute a therapeutic option for the control of hyperparathyroidism in patients with high PTH concentrations at the beginning of the treatment with chronic hemodialysis.


METHODS
Thirty-one patients with end-stage renal failure with an intact PTH concentration above 250 pg/ml at the beginning of chronic hemodialysis therapy were treated with high doses of calcium carbonate; no patient received either aluminium-containing binders or vitamin D compounds. To minimize hypercalcemia, a calcium dialysate concentration of 2.5 mEq/l was used in all patients. The goal of the study was to reduce the intact PTH concentration to 250 pg/ml with oral calcium carbonate supplements alone.


RESULTS
Throughout the first year on hemodialysis treatment, the intact PTH concentration decreased from 538 +/- 256 to 251 +/- 218 pg/ml (p < 0.001). By the end of the study, the therapeutic objective was achieved in 22 patients (71%) ('responder' group). The remaining 9 patients were classified as the 'treatment failure' group. The basal intact PTH concentration was not different between both groups (508 +/- 235 vs. 612 +/- 303 pg/ml, respectively, p = n.s.), but 5 'treatment failure' patients admitted to take a dose of calcium carbonate lower than that prescribed. There were 40 episodes of hyperphosphatemia (11% of all measurements) in 7 of 31 patients, 5 of them belonged to the noncompliance 'treatment failure' patients. Only 15 episodes (4% of all measurements) of transient hypercalcemia (range 11.1 - 11.9 mg/dl) were detected in 8 patients.


CONCLUSIONS
Secondary hyperparathyroidism in hemodialysis patients can often be reverted by oral calcium carbonate alone. But a good adherence to treatment is absolutely necessary.
Servicio de Nefrología, Hospital Ramón y Cajal, Madrid, Spain.
J L
JL
Teruel
M T
MT
Tenorio
J R
JR
Rodríguez
R
R
Marc n
L
L
Orofino
M
M
Rivera
J
J
Ortuño
D000284:Administration, Oral; D002119:Calcium Carbonate / Q000008:administration & dosage / Q000627:therapeutic use*; D002762:Cholecalciferol; D005260:Female; D006801:Humans; D006962:Hyperparathyroidism, Secondary / Q000188:drug therapy* / Q000209:etiology; D007676:Kidney Failure, Chronic / Q000150:complications / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood; D006435:Renal Dialysis
D010281:Parathyroid Hormone; D002762:Cholecalciferol; D002119:Calcium Carbonate