Clinical evaluation of two novel biointact PTH(1-84) assays in hemodialysis patients

► We compared “intact PTH” with “biointact” PTH(1-84) (assays from 2 suppliers). ► The results from both biointact PTH(1-84) assays correlated very well. ► The assays should not be used interchangeably, as indicated by Bland-Altmann plots. ► Biointact PTH(1-84) levels are roughly two third of intact PTH. ► Serum creatinine associated positively with PTH in patients with > 0 ml urine/day.