Guideline Bone Disease

In the current issue of Blood Purification, Palomares et al. [Blood Purif 2013;36:122-131] bemoan the poor level of compliance in dialysis units in achieving compliance with KDOQI and KDIGO bone and mineral guideline targets. These targets are based almost completely on observational data and rely on an obsolete assay for PTH. The so-called intact PTH assay measures both 1-84 PTH and 7-84 PTH; the latter has been demonstrated to possess biological activity that is antagonistic to that of 1-84 PTH. The assay cannot reliably distinguish high from low bone turnover in the target ranges suggested by the guideline panels. Targeting these ranges leads to an increased incidence of adynamic bone disease, higher calcium and phosphorus, and likely poor patient outcomes.