Table 1.
Clinical and biochemical characteristics of the patient cohort
| Patient | F1.1 | F1.2 | F2.1 | F3.1 | Sporadic IIH cases F4.1–F14.1 (n=11) | F15.1 nephrocalcinosis |
|---|---|---|---|---|---|---|
| Origin | Turkey | Turkey | Turkey | Turkey | Poland | |
| Age at presentation | 20 days | 1 month | 2 months | 2 months | 1–10 months | 18 months |
| Vitamin D prophylaxis | 400IE | 400IE | 500IE | 400IE | 200–2000IE (n=11) | 800IE |
| Weight loss/failure to thrive | Yes | Yes | No | Yes | 8/11 | No |
| Polyuria/dehydration | Yes | Yes | No | Yes | 8/10 | Yes |
| Muscular hypotonia | Yes | No | No | No | 3/10 | No |
| Nephrocalcinosis | Yes | Yes | Yes | Yes | 11/11 | Yes |
| Hypercalciuria | Yes | Yes | Yes | Yes | 8/11 | No |
| Initial serum calcium (mM) (2.1–2.6) | 3.5 | 2.9 | 3.1 | 3.2 | 3.1 (2.6–3.8) | 2.6 |
| Initial serum phosphate (mmol/l) | 1.0 (−5.8SDS) | 0.5 (−8.6SDS) | 1.5 (−2.8SDS) | 0.7 (−7.2SDS) | 1.2 (0.6–1.9) (−4.1SDS) | 1.7 (+0.4SDS) |
| TmP/GFR (mmol/l GF) | 0.9 (−3.3SDS) | n.d. | 1.4 (−0.3SDS) | n.d. | 0.9 (0.5–1.6) (−2.0SDS) | n.d. |
| Initial iPTH (pg/ml)(14–72) | 1.0 | 15 | 5.5 | 31 | <3 (<1–4.9) | 13 |
| Initial 25-OH-D3 (ng/ml) (10–65) | 28 | n.d. | 45 | 46 | 33.7 (15.9–56.3) | 21 |
| Initial 1,25-(OH)2D3 (pg/ml) (17–74) | 139 | n.d. | 146 | 26 | 72.3 (50.8–271) | 32 |
| Therapy (acute phase) | Ketoconazole phosphate | Rehydration | No | Rehydration steroids furosemide | Rehydration (10/10) | No |
| Steroids (3/10) | ||||||
| Bisphosphonates (1/10) | ||||||
| Therapy (long term) | Oral phosphate hydrochlorothiazide | Oral phosphate hydrochlorothiazide | No | Low calcium diet | Low calcium diet (3/11) | Potassium citrate |
| Hydrochlorothiazide (1/11) | ||||||
| Potassium citrate (2/11) | ||||||
| Oral phosphate (3/11) | ||||||
| Follow-up | ||||||
| Age at last visit | 1.5 years | 7 years | 6 years | 1.5 years | 5 years (0.5–17) | 3.5 years |
| Last serum calcium (mM) (2.1–2.6) | 2.7 | 2.5 | 2.4 | 2.8 | 2.6 (2.5–2.7) (11/11) | 2.7 |
| Last serum phosphate (mM) | 0.9 (−4.1SDS) | 1.1 (−1.7SDS) | 1.5 (+0.5SDS) | 1.8 (+0.9SDS) | 1.5 (0.9–1.8) (+0.1SDS) | 1.7 (+1.3SDS) |
| TmP/GFR (mmol/l GF) | 0.8 (−3.0SDS) | 1.0 (−2.0SDS) | 1.3 (−0.5SDS) | n.d. | 1.3 (−0.5SDS) | 1.6 (+1.0SDS) |
| Last PTH (pg/ml)(14–72) | 21 | 23 | 20 | 42 | 16 (7.1–33) | 22 |
| FGF23 (kRU/l)(26–110) | 136 | n.d. | n.d. | 77 | 51 (29–114) | n.d. |
| Last 25-OH-D3 (ng/ml) (10–65) | 8 | 12 | 26 | 36 | 26 (15–63) | 38 |
| Last 1,25-(OH)2D3 (pg/ml) (17–74) | 57 | 75 | 58 | n.d. | 59 (35–146) | 54 |
| SLC34A1 mutations nucleotide level | c.644(+1)g>a homoz. | c.644(+1)g>a homoz. | c.458G>T homoz. | c.1006(+1)g>a homoz. | See Supplemental Material | c.271_91del homoz. |
| SLC34A1 mutations protein level | IVS6(+1)g>a homoz. | IVS6(+1)g>a homoz. | p.G153V homoz. | IVS9(+1)g>a homoz. | See Supplemental Material | p.91del7 homoz. |
The individual data are provided for the patients from consanguinous families F1–F3 used for homozygosity mapping as well as for patient F15.1 who presented with polyuria and nephrocalcinosis. The data of sporadic cases of IIH (F4.1–F14.1) are summarized. For clinical symptoms the proportion of affected patients is provided, the values indicated for laboratory parameters correspond to median and range. For serum phosphate and TmP/GFR, age-dependent SDS are provided (for sporadic cases median SDS). GF, glomerular filtrate; n.d., no data available.