Bone alkaline phosphatase isoforms in CKD patients on hemodialysis with low and high bone turnover
2014 (English)Manuscript (preprint) (Other academic)
Background: Renal osteodystrophy encompasses the bone histologic abnormalities seen in patients with chronic kidney disease (CKD). The bone-specific alkaline phosphatase (BALP) isoform B1x is exclusively found in serum of some CKD patients.
Study Design: The aim of this cross-sectional diagnostic test study was to examine the relationship between serum BALP isoform activities and histomorphometric parameters of bone in patients with CKD on chronic hemodialysis.
Setting & Participants: Anterior iliac crest bone biopsy samples from 40 CKD patients were selected on the basis of bone turnover for histomorphometric analysis. There were samples from 20 patients with low and 20 with non-low bone turnover.
Index Test: In serum, BALP, BALP isoforms (B/I, B1x, B1 and B2), and parathyroid hormone (PTH) were measured.
Reference Test or Outcome: Indices of osteoblastic activity and number.
Other Measurements: Parathyroid hormone
Results: B1x was found in 21 patients (53%) who had lower median levels of BALP, 18.6 versus 46.9 U/L; B/I, 0.10 versus 0.22 μkat/L; B1, 0.40 versus 0.88 μkat/L; B2, 1.21 versus 2.66 μkat/L; and PTH, 49 versus 287 pg/mL, compared to patients without B1x (p<0.001). B1x correlated inversely with osteoblast number and activity. ROC curves showed that B1x (AUC 0.83) can be used for diagnosis of low osteoblastic activity, while BALP (AUC 0.78) and PTH (AUC 0.77) are useful for diagnosis of high osteoblast number seen with high bone turnover.
Limitations: Small number of study participants.
Conclusions: The presence of B1x in serum may be a sign of perturbed osteoblast activity and it may be useful as a diagnostic parameter for low bone turnover rate.
Place, publisher, year, edition, pages
Bone-specific alkaline phosphatase; isoforms; renal osteodystrophy; osteoblast activity; low bone turnover
IdentifiersURN: urn:nbn:se:liu:diva-111868OAI: oai:DiVA.org:liu-111868DiVA: diva2:761377