Table 2.
Laboratory and radiographic findings by kidney stone group among 1957 potential kidney donors evaluated at the Mayo Clinic between 2000 and 2008
| Group 1: no radiographic or past symptomatic stones (N = 1719) | Group 2: asymptomatic radiographic stones only (N = 185) | Group 3: past symptomatic stones (N = 53)a | P-value | ||
| Characteristic | Mean ± SD or n (%) | Mean ± SD or n (%) | Mean ± SD or n (%) | Group 1 versus 2 | Groups 1 and 2 versus 3 |
| GLomerualr filtration rate, mL/min/1.73 m2 | 101 ± 19 | 102 ± 21 | 102 ± 19 | 0.29 | 0.60 |
| 24-h urine volume, mL | 2045 ± 904 | 1960 ± 868 | 1807 ± 884 | 0.34 | 0.06 |
| 24-h urine volume < 1000 mL | 166 (10) | 27 (15) | 9 (17) | 0.028 | 0.12 |
| 24-h urine protein, mg | 48 ± 41 | 55 ± 49 | 55 ± 43 | 0.071 | 0.32 |
| 24-h urine albumin > 15 mg | 144 (9.0) | 18 (11) | 12 (23) | 0.49 | 0.0007 |
| 24-h urine albumin > 30 mg | 56 (3.5) | 6 (3.6) | 7 (13) | 0.96 | 0.0002 |
| Total cholesterol, mg/dL | 197 ± 38 | 199 ± 41 | 203 ± 49 | 0.90 | 0.75 |
| Fasting glucose, mg/dL | 96 ± 9.5 | 96 ± 9.8 | 97 ± 11 | 0.29 | 0.48 |
| Serum uric acid, mg/dL | 5.4 ± 1.4 | 5.2 ± 1.4 | 5.2 ± 1.3 | 0.12 | 0.55 |
| Serum calcium, mg/dL | 9.6 ± 0.3 | 9.6 ± 0.4 | 9.6 ± 0.3 | 0.64 | 0.69 |
| Serum phosphorus, mg/dL | 3.5 ± 0.5 | 3.5 ± 0.5 | 3.3 ± 0.5 | 0.06 | 0.002 |
| Any upper tract dilatation | 38 (2.2) | 8 (4.3) | 3 (5.7) | 0.08 | 0.14 |
| Medullary sponge kidney | 17 (1) | 19 (10) | 4 (7.6) | <0.0001 | <0.0001 |
| Focal scarring | 49 (2.9) | 15 (8.1) | 6 (11) | 0.0002 | 0.002 |
| Parenchymal thinning/atrophy | 11 (0.6) | 5 (2.7) | 1 (1.9) | 0.004 | 0.42 |
| Polycystic kidney disease | 1 (0.1) | 5 (2.7) | 0 (0) | <0.0001 | 0.68 |
a
Subjects included those with and without current radiographic stones.