Direct comparison between two 1-84PTH assays in dialysis patients.
OBJECTIVE
Today, two kinds of 1-84PTH assays are available in clinical practice. Few studies have directly compared the results of these assays in the same plasma.


METHODS
Plasma samples were collected from 235 dialysis patients and analyzed by the 1-84PTH-IRMA, intact PTH-IRMA, 1-84PTH-CLIA, and intact PTH-CLIA assays simultaneously.


RESULTS
The results obtained by the 1-84PTH-IRMA and 1-84PTH-CLIA were highly correlated to each other (r(2) = 0.971, p < 0.0001). In 90.2-92.3% of patients, the assays agreed when classifying them into three categories based on the K/DOQI guidelines. However, the 1-84PTH assays agreed in only 41.3-83.4% of patients when classifying them into two categories by calculating 1-84PTH/(intact PTH - 1-84PTH).


CONCLUSIONS
The results obtained by the two assays could be regarded as comparable in clinical practice. However, the 1-84PTH/(intact PTH-1-84PTH) ratio has to be carefully applied since it amplified the error of these assays.
Kazama
Junichiro J
JJ
Division of Clinical Nephrology and Rheumatology, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan. jjkaz@med.niigata-u.ac.jp <jjkaz@med.niigata-u.ac.jp>
Yamamoto
Suguru
S
Kameda
Shigemi
S
Maruyama
Hiroki
H
Narita
Ichiei
I
Shigematsu
Takashi
T
Gejyo
Fumitake
F
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000911:Antibodies, Monoclonal; D012080:Chronic Kidney Disease-Mineral and Bone Disorder / Q000097:blood; D000939:Epitopes; D005260:Female; D005921:Glomerulonephritis / Q000175:diagnosis* / Q000628:therapy; D006801:Humans; D015592:Immunoradiometric Assay; D008163:Luminescent Measurements; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood; D006435:Renal Dialysis
D000911:Antibodies, Monoclonal; D000939:Epitopes; D010281:Parathyroid Hormone; D010446:Peptide Fragments; C040288:amino-terminal parathyroid hormone; C023443:carboxyl-terminal parathyroid hormone