Table 1.
Demographics, Stone Type, and Metabolic Studies of Patients with or without Stent Encrustation
| Characteristic | Nonencrusted (n = 22) | Encrusted (n = 5) | p-Valuea |
|---|---|---|---|
| Male, n (%) | 8 (36) | 2 (40) | NS |
| Age, mean (SD) | 47 (11) | 56 (5) | NS |
| Days indwelling (SD) | 8 (2) | 8 (2) | NS |
| Visual encrustation scale, n | |||
| 0 | 4 | – | – |
| 1 | 18 | – | – |
| 2 | – | 3 | – |
| 3 | – | 1 | – |
| 4 | – | 1 | – |
| Stone type, n | |||
| Calcium oxalate | 14 | 1 | 0.14 |
| Mixed | 2 | 3 | 0.03 |
| Calcium phosphate | 3 | – | NS |
| Urate | 1 | – | NS |
| None | 1 | 1 | NS |
| 24-hour urine,bn (%) | |||
| Hypocitraturia (<450 mg) | 11 (50) | 3 (60) | NS |
| Hyperuricosuria (>800 mg) | 11 (50) | 0 | 0.06 |
| Low volume (<1.5 L) | 6 (27) | 5 (100) | 0.01 |
| Hypercalciuria (>250 mg) | 5 (23) | 1 (20) | NS |
| Hyperoxaluria (>40 mg) | 3 (14) | 2 (40) | 0.22 |
| pH (5.0–8.0) | 6.11 | 5.74 | NS |
| None performed | 6 (27) | 0 | NS |
a
Actual value reported if p < 0.25, otherwise NS.
b
Several individuals had multiple abnormalities. Normal values are based on standard urinary metabolic guidelines and represented by mg or L/day.
NS = nonsignificant.