Table 1.
Patient characteristics
| Bartter syndrome | Bartter syndrome | Bartter syndrome | Gitelman | ||
|---|---|---|---|---|---|
| type I and II | type III | NOS | syndrome | Total | |
| Number of patients | 107 | 88 | 90 | 304 | 589 |
| Characteristics | |||||
| Male: Female ratio, n (%) | 51: 56 (48: 52) | 50: 38 (57: 43) | 48: 42 (53: 47) | 133: 171 (44: 56) | 282: 307 (48: 52) |
| Age (years) | 9.0 [3.5–16.0] | 10.4 [3.3–17.2] | 9.6 [3.6–16.3] | 28.8 [16.4–43.9] | 16.6 [8.2–33.5] |
| Nephrocalcinosis, n (%) | 90/101 (89) | 15/85 (18) | 46/82 (56) | 4/257 (2) | 155/525 (30) |
| Laboratory results | |||||
| iPTH (pmol/L) | 7.5 [4.8–11.2] | 4.4 [3.0–6.7] | 5.1 [2.9–8.3] | 3.1 [2.3–4.0] | 3.8 [2.5–6.6] |
| Creatinine (umol/L) | 55 [37–76] | 43 [–62] | 48 [–66] | 58 [47–71] | 55 [41–70] |
| Sodium (mmol/L) | 140 [138–142] | 139 [137–141] | 139 [137–140] | 139 [138–141] | 139 [138–141] |
| Potassium (mmol/L) | 3.6 [3.3–3.8] | 3.2 [2.8–3.6] | 3.4 [3.0–3.9] | 3.0 [2.7–3.4] | 3.2 [2.8–3.7] |
| Chloride (mmol/L) | 99 [97–101] | 97 [92–100] | 96 [93–101] | 98 [95–100] | 98 [95–100] |
| Bicarbonate (mmol/L) | 26.2 [24.3–28.1] | 29.0 [26.3–32.0] | 28.4 [27.0–30.7] | 29.0 [27.0–31.0] | 28.3 [26.3–31.0] |
| Phosphate (mmol/L) | 1.42 [1.21–1.63] | 1.28 [1.09–1.44] | 1.30 [1.12–1.53] | 1.07 [0.92–1.25] | 1.21 [0.99–1.42] |
| Phosphate-SDS | -0.67 [-1.76–0.43] | −1.34 [-2.31– −0.15] | −1.32 [−2.32–0.05] | -0.77 [−1.51–0.29] | −0.91 [−1.82–0.18] |
| Calcium (mmol/L) | 2.44 [2.37–2.53] | 2.48 [2.40–2.58] | 2.50 [2.38–2.60] | 2.41 [2.31–2.50] | 2.43 [2.34–2.53] |
| Magnesium (mmol/L) | 0.89 [0.80–0.97] | 0.77 [0.68–0.85] | 0.81 [0.75–0.95] | 0.63 [0.56–0.71] | 0.71 [0.61–0.84] |
| Uric acid (µmol/l) | 315 [246–405] | 220 [162–319] | 286 [190–409] | 250 [190–321] | 262 [190–350] |
| Alkaline phosphatase (IU/L) | 227 [161–287] | 212 [114–274] | 230 [160–303] | 66 [51–136] | 148 [62–245] |
| Alkaline phosphatase-SDS | 0.79 [−0.05–1.52] | 0.21 [−0.50–0.99] | 0.65 [−0.36–1.89] | −1.00 [−1.72–0.00] | −0.13 [−1.18–0.93] |
| Total protein (g/L) | 73 [70–77] | 73 [69–76] | 75 [71–78] | 73 [69–76] | 73 [70–77] |
| Albumin (g/L) | 46 [43–49] | 45 [43–48] | 46 [43–49] | 46 [44–49] | 46 [43–49] |
| 25OH vitamin D (nmol/L) | 39 [–68] | 40 [–82] | 43 [–64] | 61 [–85] | 51 [–80] |
| Urinary calcium/creatinine (mmol/mmol) | 1.55 [0.94–2.62] | 0.33 [0.14–0.71] | 0.55 [0.23–1.14] | 0.08 [0.04–0.17] | 0.21 [0.07–0.75] |
| TRP | 0.90 [0.81–0.92] | 0.90 [0.86–0.93] | 0.88 [0.82–0.95] | 0.91 [0.86–0.94] | 0.90 [0.85–0.94] |
| TmP/GFR (mmol/L) | 1.41 [1.10–1.48] | 1.17 [1.02–1.33] | 1.11 [0.84–1.35] | 0.95 [0.82–1.10] | 1.04 [0.84–1.23] |
| TmP/GFR-SDS | 0.23 [−0.46–0.78] | −0.62 [−1.48–0.44] | −0.66 [−2.03–0.14] | −0.98 [−1.47– −0.46] | −0.86 [−1.54– −0.02] |
| Treatment | |||||
| NSAIDs, n (%) | 69 (65) | 52 (59) | 55 (61) | 26 (9) | 202 (34) |
| Indomethacin, n (%) | 53 (50) | 48 (55) | 54 (60) | 26 (9) | 181 (31) |
| Ibuprophen, n (%) | 16 (15) | 4 (5) | 2 (2) | 0 (0) | 22 (4) |
| Other NSAIDs, n (%) | 5 (5) | 7 (8) | 4 (4) | 1 (0.3) | 17 (3) |
| Potassium-sparing diuretics, n (%) | 2 (2) | 12 (14) | 4 (4) | 63 (21) | 81 (14) |
| Amilorid, n (%) | 2 (2) | 12 (14) | 4 (4) | 58 (19) | 76 (13) |
| Triamterene, n (%) | 0 (0) | 0 (0) | 0 (0) | 5 (2) | 5 (1) |
| Aldosterone antagonists, n (%) | 5 (5) | 17 (19) | 23 (26) | 54 (18) | 99 (17) |
| Eplerenone, n (%) | 1 (1) | 2 (2) | 6 (7) | 15 (5) | 24 (4) |
| Spironolactone, n (%) | 4 (4) | 15 (17) | 16 (18) | 37 (12) | 72 (12) |
| Canrenone, n (%) | 0 (0) | 0 (0) | 1 (1) | 2 (1) | 3 (1) |
| ACE inhibitors/ARBs, n (%) | 4 (4) | 5 (6) | 0 (0) | 6 (2) | 15 (3) |
| Hydrochlorothiazide, n (%) | 3 (3) | 0 (0) | 6 (7) | 0 (0) | 9 (2) |
| Potassium supplements, n (%) | 71 (66) | 83 (94) | 76 (84) | 280 (92) | 510 (87) |
| Sodium supplements, n (%) | 28 (26) | 44 (50) | 21 (23) | 43 (14) | 136 (23) |
| Magnesium supplements, n (%) | 11 (10) | 21 (24) | 18 (20) | 226 (74) | 276 (47) |
| Phosphate supplements, n (%) | 0 (0) | 2 (2) | 3 (3) | 1 (0,3) | 6 (1) |
| Proton pump inhibitors, n (%) | 20 (19) | 24 (27) | 14 (16) | 39 (13) | 97 (17) |
| Other gastric protectors, n (%) | 12 (11) | 10 (11) | 8 (9) | 11 (4) | 41 (7) |
| Oral contraceptive, n (%) | 1 (1) | 1 (1) | 1 (1) | 20 (7) | 23 (4) |
| Vitamin D supplements, n (%) | 41 (38) | 20 (23) | 17 (19) | 26 (9) | 104 (18) |
iPTH, intact parathyroid hormone; phosphate-SDS, age-related phosphate standard deviation score; alkaline phosphatase-SDS, age-related alkaline phosphatase standard deviation score; 25OH vitamin D, 25-hydroxy vitamin D; TRP, tubular reabsorption of phosphate; TmP/GFR, ratio of tubular maximum reabsorption of phosphate to GFR; TmP/GFR-SDS: age-related TmP/GFR standard deviation score; NSAIDs, nonsteroidal anti-inflammatory drugs; ACE inhibitors, angiotensin converting enzyme inhibitors; ARBs, angiotensin II receptor blockers.
Categorical values are presented as number and % given in parentheses. Continuous values are presented as median with interquartile range (IQR) given in square brackets.
Nota bene: some patients are using more than one NSAID according to the provided data.