Elevated bone aluminum and suppressed parathyroid hormone levels in hypercalcemic dialysis patients

Am J Nephrol. 1989;9(3):190-7. doi: 10.1159/000167964.

Abstract

We studied 21 dialysis patients who became hypercalcemic without vitamin D or calcium therapy and compared them to 28 dialysis patients who were not hypercalcemic. In the hypercalcemic group, the mean ionized-calcium level was elevated compared to normal subjects (5.4 +/- 0.4 vs. 4.9 +/- 0.1; p less than 0.001), while the ionized-calcium level in the control dialysis patients was below normal (4.5 +/- 0.4 vs. 4.9 +/- 0.1; p less than 0.001). Bone biopsies were performed in all patients. Two thirds of the hypercalcemic patients had low-turnover osteodystrophy (LTO, predominantly osteomalacia), a fraction significantly higher than in the control dialysis patients (13/21 vs. 8/28, respectively; p less than 0.05). The hypercalcemic patients with LTO had markedly elevated surface bone aluminum (63 +/- 24% of all trabecular surfaces). In contrast, the nonhypercalcemic dialysis patients with LTO and all patients with osteitis fibrosa had minimal surface bone aluminum. Hypercalcemic patients with osteitis fibrosa had a significantly lower mean N-terminal parathyroid hormone (PTH) value than did nonhypercalcemic patients with osteitis fibrosa (149 +/- 81 vs. 278 +/- 135 pg/ml, respectively; p less than 0.005). Both mean values were markedly elevated in comparison with those obtained in normal subjects (16 +/- 5 pg/ml). In contrast, patients with LTO, irrespective of the calcium level, had mean PTH values that were not significantly different from those of normal subjects. A PTH level greater than 100 pg/ml was 95% sensitive and 87% specific for osteitis fibrosa, as demonstrated by histomorphometry in nonhypercalcemic dialysis patients. However, this level was only 62% sensitive and 77% specific for a diagnosis of osteitis fibrosa in hypercalcemic dialysis patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adult
  • Aged
  • Aluminum / metabolism*
  • Bone and Bones / metabolism*
  • Bone and Bones / pathology
  • Chronic Kidney Disease-Mineral and Bone Disorder / complications*
  • Chronic Kidney Disease-Mineral and Bone Disorder / pathology
  • Female
  • Fibrous Dysplasia of Bone / complications
  • Follow-Up Studies
  • Humans
  • Hypercalcemia / etiology
  • Hypercalcemia / metabolism*
  • Hypercalcemia / mortality
  • Hypercalcemia / pathology
  • Male
  • Middle Aged
  • Parathyroid Hormone / blood*
  • Renal Dialysis*

Substances

  • Parathyroid Hormone
  • Aluminum