Table 2.
Characteristics of IRCU patients with either low or high pH in fasting urine, and of all patients
| pH; median 6.14 | ||||||
|---|---|---|---|---|---|---|
| Low | High | High vs. Low | All | |||
| N | ≤Median | > Median | p | Mean | Range | |
| General features | ||||||
| ASFP; score | 187 | 40 (5); 93 | 35 (3); 94 | 0.49x | a | b |
| Renal stones; Absent/Present | 187 | 57/36 | 37/57 | 0.03xx | ||
| BMI; kg/(m)2 | 187 | 27.0 (0.4); 93 | 25.6 (0.3); 94 | 0.001 | a | b |
| P*-Insulin; μU/ml | 184 | 20 (1); 90 | 13 (1); 94 | < 0.001 | a | b |
| Systolic blood pressure; mm Hg | 152 | 130 (3); 74 | 128 (2); 78 | 0.24 | a | b |
| Diastolic blood pressure; mm Hg | 152 | 84 (2); 74 | 83 (1); 78 | 0.29 | a | b |
| U*-Hypoxanthine; μM | 75 | 11 (0.9); 40 | 13 (0.6); 35 | 0.03x | a | b |
| U-Xanthine; μM | 75 | 5.2 (0.5); 40 | 7.7 (0.5); 35 | < 0.001x | a | b |
| P-Uric acid; μM/l | 187 | 374 (7), 93 | 342 (7); 94 | 0.001 | a | b |
| P-TAS; mM/l | 57 | 1.35 (0.02); 29 | 1.32 (0.02); 28 | 0.14 | a | b |
| P-Oxalate; μM | 61 | 1.72 (0.09); 32 | 1.71 (0.08); 29 | 0.46 | 1.9 | 1.1-3.8 |
| U-MDA; nM | 176 | 124 (5); 89 | 140 (7); 87 | 0.03 | a | b |
| B*-pH | 185 | 7.40 (0.00); 91 | 7.41 (0.00); 94 | 0.02 | 7.401 | 7.35-7.49 |
| B-Bicarbonate; mM/l | 185 | 23.2 (0.2); 91 | 23.7 (0.2); 94 | 0.07 | 23.52 | 18-31 |
| U-MDA/P-Uric acid; nM/mM × l-1 | 176 | 345 (17); 90 | 426 (22); 86 | 0.002 | a | b |
| Urine | ||||||
| pH | 187 | 5.46 (0.04); 93 | 6.81 (0.04); 94 | < 0.001 | a | b |
| Volume; ml | 187 | 194 (14); 93 | 256 (17); 94 | 0.003 | a | b |
| Cr**-Clearance; ml/min | 187 | 127 (4); 93 | 119 (3); 94 | 0.08 | a | b |
| N-Alb-P; mg/l | 181 | 32 (5); 89 | 34 (5); 92 | 0.24x | 33 | 2-435 |
| 103 × FE-N-Alb-P; % | 187 | 1.9 (0.3); 91 | 2.5 (0.5); 96 | 0.002x | a | b |
| FE-Uric acid; % | 186 | 7.7 (0.3); 92 | 8.5 (0.4); 94 | 0.07 | a | b |
| FE-Oxalate; % | 61 | 108 (8); 32 | 120 (9); 29 | 0.16 | 113 | 40-245 |
| Na; mM/l | 187 | 77 (4); 93 | 66 (4); 94 | 0.03 | 72 | 13-201 |
| Ca; mM/l | 187 | 2.1 (0.2); 93 | 1.9 (0.2); 94 | 0.18x | 2.0 | 0.2-11 |
| Pi; mM/l | 187 | 8.6 (0.7); 93 | 7.7 (0.8); 94 | 0.20x | 8.2 | 0.4-66 |
| Ox; μM/l | 179 | 144 (10); 87 | 110 (8); 92 | 0.003x | 130 | 3-470 |
| Uric acid; mM/l | 187 | 2.7 (0.1); 93 | 2.2 (0.1); 94 | 0.005 | 2.4 | 0.39-6.1 |
| Uric acid; DG | 187 | 5.26 (0.16); 85 | 4.45 (0.17); 87 | < 0.001 | 0.82 | 8.13 |
| Ca/Pi; mM/mM | 187 | 0.39 (0.04); 93 | 0.40 (0.06); 94 | 0.49 | 0.40 | 0.05-3.7 |
| Total Mg; mM/l | 187 | 1.75 (0.13); 93 | 1.38 (0.08); 94 | 0.005 | 1.6 | 0.21-4.58 |
| Complexed Mg; mM/l | 172 | 0.83 (0.06); 85 | 0.71 (0.06); 87 | 0.08 | 0.77 | 0.1-2.8 |
| F-Mg; mM/l | 172 | 0.95 (0.06); 85 | 0.70 (0.05); 87 | 0.001 | 0.82 | 0.1-2.8 |
| Total Cit; mM/l | 185 | 1.93 (0.13); 93 | 1.61 (0.13); 92 | 0.03x | 1.8 | 0.18-5.9 |
| Complexed Cit; mM/l | 172 | 1.63 (0.12); 85 | 1.33 (0.11); 87 | 0.03 | 1.5 | 0.2-5.2 |
| F-Cit; mM/l | 172 | 0.29 (0.03); 85 | 0.31 (0.03); 87 | 0.31 | 0.30 | 0.02-1.5 |
| CaOx; DG | 172 | 1.0 (0.11); 85 | 0.78 (0.13); 87 | 0.06 | 0.91 | -2.7-3.5 |
| HAP; DG | 172 | 1.9 (0.32); 85 | 3.7 (0.28); 87 | < 0.001 | 2.8 | -4.6-8.6 |
Excretion rates are per 2 h. N: number of participating patients; for the number of patients in strata, data for a and b and other information, see Table 1 and text.
*: P, U and B indicate plasma, urine and blood, respectively; **: creatinine; x: based on log10; xx:Chi2 9.0 (3 degrees of freedom); 1, 2: limits of normalcy in the authors' laboratory are ≥7.35, ≥18, respectively.