Table 3.
Characteristics of patients with MAGED2 mutations compared with antenatal Bartter syndrome types 1–4
| Clinical Data (Neonatal Period) | Normal Values (When Applicable) | MAGED2 (n=17) | Type 1 (SLC12A1) (n=41) | Type 2 (KCNJ1) (n=43) | Type 3 (CLCNKB)a (n=32) | Type 4a (BSND) (n=13) | P Value (Kruskal–Wallis Test) |
|---|---|---|---|---|---|---|---|
| Onset of polyhydramnios (wk of gestation) | 23 (25–22)2 | 24 (22–27)15 | 25 (23–28)16 | 29 (23.5–32)15 | 22 (22–24)8 | NS | |
| Amniotic fluid index, cm | <24 | 42 (41–43)9 | 4440 | 38 and 4041 | ND | ND | — |
| Bartter index | 0.73 (0.52–0.86)4 | 0.64 (0.35–0.94)33 | 1.20 (0.38–1.96)35 | 1.29 (0.60–1.98)30 | ND | — | |
| Number of amnioreductions | 2 (1–4) | 2 (1–3)5 | 2 (1–4)6 | 1 (1–1)2 | 1 (1–2)6 | — | |
| Gestational age at delivery, wk | 40 | 29.5 (26–31) | 32 (29–34)2 | 33 (32–35)2 | 37 (36–40) | 31 (28–34)4 | P<0.001 |
| B, C | |||||||
| Weight at birth, % | 10–90 | 94 (86–97) | 42 (14–68)5 | 49 (11–73)6 | 39 (17–70)2 | 39 (17–70)2 | P<0.001 |
| A, B, C, D | |||||||
| Height at birth, % | 10–90 | 94 (85–98)2 | 72 (43–94)20 | 59 (31–984)13 | 64 (29–85)11 | 59 (35–79)5 | P=0.001 |
| B, C, D | |||||||
| Diuresis, ml/kg per h | 1–3 | 15 (6–27)1 | 7 (4–13)28 | 6 (4–10)32 | 5 (3–8)32 | 5 (3–8)26 | — |
| Placenta weight to birth weight ratio according to wk gestation, % | n=9 | n=3 | n=1 | n=1 | ND | — | |
| 45 (27–75) | 50 (30–60) | 91 | 8 | ||||
| Nephrocalcinosis at diagnosis | 17 (10%) | 1911 (63%) | 1610 (48%) | 88 (33%) | 42 (36%) | P=0.02 | |
| Last follow-up | |||||||
| Age, yr | 5 (2–8)3 | 10 (7–16)19 | 13 (5–19)7 | 7 (4–12)14 | 13 (8–17) | P<0.01 | |
| A, B, D | |||||||
| Weight, % | 28 (6–64)1 | 25 (4–67)18 | 7 (4–12)26 | 44 (71/10–69)15 | 44 (7–69)15 | NS | |
| Height, % | 57 (11–82)2 | 12 (1–47)19 | 13 (3–45)16 | 16 (7–73)15 | 0.2 (0.1–73)2 | NS | |
| Kidney function (eGFR) | 116 (104–158)4 | 71 (62–81)11 | 89 (78–99)10 | 118 (85–136)14 | 77 (32–113)2 | P<0.001 | |
| A, B, D | |||||||
Values are expressed as medians and interquartile ranges. Superscript values correspond to the numbers of missing data. The differences previously described between types 1–4 are represented in Supplemental Figures 1–4. ND, no data; —, not done; B, P<0.01 MAGED2 versus type 2; C, P<0.01 MAGED2 versus type 3; A, P<0.01 MAGED2 versus type 1; D, P<0.01 MAGED2 versus type 4a.
a
Bartter three patients with antenatal phenotype.