Evaluation of IDS-iSYS intact parathyroid hormone (iPTH) and comparison to Siemens Advia Centaur iPTH assay in chronic renal failure patients and in controls.
BACKGROUND
IDS-iSYS intact parathyroid hormone (iPTH) assay was evaluated. Two automated second generation assays for measuring iPTH were also compared to each other. The compared assays detected PTH fragments 1-84 and 5-84.


METHODS
The iPTH was analyzed from controls (n = 88) and samples of patients with chronic kidney disease (CKD) (n = 100) on the IDS-iSYS (iSYS) and Siemens ADVIA Centaur (Centaur) immunoanalyzers.


RESULTS
In controls, the iSYS method mean value (95% CI ranges) was 37.1 pg/mL (34.3 to 39.9) and the Centaur was 39.3 pg/mL (36.3 to 42.3). The regression coefficient (r) between the iSYS and the Centaur was 0.850 in controls. Correspondingly, in CKD patients the iSYS method mean value (95% CI ranges) was 183.3 pg/mL (154.3 to 212.4) and the Centaur was 199.7 pg/mL (170.4 to 229.0). In CKD patients the regression coefficient (r) between the iSYS and the Centaur was 0.964. With Passing-Bablok analysis, the automated iPTH methods gave clinically similar results in controls and in CKD patients. However, in the difference blots, the iSYS gave lower concentrations when the mean concentration increased.


CONCLUSIONS
The IDS-iSYS iPTH assay is precise. The iSYS concentrations of iPTH were clinically similar with those determined by Centaur.
Institute of Diagnostics, Department of Clinical Chemistry, University of Oulu, Finland.
Marja-Kaisa
MK
Koivula
Päivi
P
Laitinen
Juha
J
Risteli
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001322:Autoanalysis; D005260:Female; D006801:Humans; D006962:Hyperparathyroidism, Secondary / Q000097:blood*; D007118:Immunoassay; D007676:Kidney Failure, Chronic / Q000097:blood*; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood*; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D055815:Young Adult
D010281:Parathyroid Hormone