PTH: Redefining Reference Ranges in a Healthy Population—The Role of Interfering Factors and the Type of Laboratory Assay
Table 3
Laboratory data categorized on the basis of 25OHD3 levels deficiency (≥50 nmol/L) or sufficiency (≥75 nmol/L), expressed in mean ± standard deviation and median values and the range of the values. Reference ranges: calcium: 2.10–2.55 nmol/L; creatinine: male subjects: 59–104 μmol/L, female subjects: 45–84 μmol/L; phosphate: 0.87–1.45 mmol/L; 3rd generation PTH assay: 4.6–26.8 pg/ml; 2nd generation PTH assay: 10–57 pg/ml.
All patients 108 (100%)
25OHD3 < 50 nmol/L 61 (56.5%)
25OHD3 ≥ 50 nmol/L 47 (43.5%)
value
25OHD3 < 75 nmol/L 101 (93.5%)
25OHD3 ≥ 75 nmol/L 7 (6.5%)
value
Calcium (mean values ± SD) (mmol/L)
2.4 ± 0.1
2.4 ± 0.1
2.4 ± 0.1
0.69
2.4 ± 0.1
2.4 ± 0.1
0.64
Phosphate (mean values ± SD) (mmol/L)
1.1 ± 0.2
1.1 ± 0.2
1.1 ± 0.2
0.12
1.1 ± 0.2
1.3 ± 0.1
0.03
Creatinine (mean values ± SD) (μmol/L)
77.4 ± 13.0
79.2 ± 14.1
74.9 ± 11.2
0.07
77.9 ± 13.1
70.4 ± 10.9
0.07
2nd generation (median values and range) (pg/ml) PTH
16.0 (7.0–69.0)
17.5 (7.0–69.0)
14.0 (7.0–48.0)
0.09
16.0 (7.0–69.0)
14.0 (8.4–36.0)
0.28
3rd generation (median values and range) (pg/ml) PTH
