Table 1.
Demographic, Laboratorial, and Clinical Data of the Study Population Stratified by Age Group
| Children | Adults | P | |
|---|---|---|---|
| n (female/male) | 16 (12/4) | 23 (18/5) | - |
| Age, y | 11.7 ± 5.2 | 41.9 ± 15.3 | - |
| z score of height | −2.4 ± 1.4 | −3.4 ± 1.5 | <0.05 |
| PTH (NR: 15–65 pg/mL) | 78.4 ± 37 | 64.5 ± 33.1 | 0.27 |
| FGF23 (NR: 10–50 pg/mL) | 132.3 ± 53.8 | 85.4 ± 26.9 | <0.01 |
| Urine P/Cr ratio | 1.62 ± 0.69 | 0.56 ± 0.19 | <0.01 |
| Phosphaturia, mg/kg/d | 24.1 ± 12.9 | 8.2 ± 2.5 | <0.01 |
| TmP/GFRa | 2.2 ± 0.56 | 1.9 ± 0.50 | 0.15 |
| TRP | 78.8 ± 8.5 | 81.2 ± 10.7 | 0.43 |
| Age at treatment initiation, y | 2.8 ± 2.3 | 8.0 ± 3.2 | <0.01 |
| Duration of phosphate treatment, y | 8.3 ± 4.6 | 11.5 ± 4.4 | 0.64 |
| Phosphate treatment during childhood, n | 16/16 | 14/23 | <0.01 |
| Phosphate dosage, mg/kg/d | 30–60 | Not available | |
| Calcitriol treatment during childhood, n | 16/16 | Not available | |
| Calcitriol dosage, ng/kg/d | 15–60 | Not available | |
| Tertiary hyperparathyroidism, % | None | 3/23 (13%) | |
| Presence of NC, % | 9/16 (56.2%) | 6/23 (26.1%) | 0.05 |
| Family history of NC, % | 5/16 (31.3%) | 4/23 (17.4%) | 0.44 |
| Presence of NL, % | None | 4/23 (17.4%) |
Values are expressed as mean ± SD as appropriate. P represents the significance of the differences between the pediatric and adult groups. A P value <0.05 was considered statistically significant.
Abbreviations: Cr, creatinine; NR, normal range; P, phosphate; PTH, parathyroid hormone; TmP/GFR, tubular maximum reabsorption of phosphate per unit of glomerular filtrate; TRP, tubular reabsorption of phosphorus.
a
Children adjusted for age; adults compared as Bijvoet pairs.