Table 1.
Clinical and Biochemical Characteristics
| Case 1 | Case 2 | Case 3 | |
|---|---|---|---|
| Age | 5 y 6 mo | 2 y 7 mo | 4 y 8 mo |
| Duration of ketogenic diet | 5 mo | 1 y | 8 mo |
| Diagnosis | Undiagnosed neurodegenerative disorder | Chromosomal 2q24.3 deletion | Cortical dysplasia |
| Antiepileptic medications | Levetiracetam, oxcarbazepine | Topiramate | None |
| Bicarbonate therapy | Yes | Yes | Yes |
| Ambulatory | No | No | Yes |
| Vitamin D supplementation | Yes | Yes | Yes |
| Calcium supplementation | No | Yes (50 mg/kg/d) | Yes (35 mg/kg/d) |
| Serum calcium, mg/dL (ref, 8.8–10.1) | 12.3 | 13.9 | 13.2 |
| Urinary calcium:creatinine, mg/mg (ref, <0.2) | 0.32 | 0.29 | 0.2 |
| Serum phosphorus, mg/dL (ref, 3.8–6.5) | 5.1 | 4.8 | 6.1 |
| Alkaline phosphatase, U/L (ref, 145–320) | 66 | 108 | 107 |
| 25(OH)D, ng/mL (ref, 30–80) | 33.9 | 39.9 | 33.7 |
| 1,25(OH)2D, pg/mL (ref, 15–75) | 11 | <3 | |
| PTH, pg/mL (ref, 9–52) | <3.4 | 4.8 | <10 |
| Urinary N-telopeptide, nmol BCE/mmol Cr | ND | 214 | 152 |
| Serum C-telopeptide, pg/mL | ND | 479 | 126 |
| Serum PTHrP (pmol/L) (ref, 0–4) | <3.3 | <3 | <1.5 |
| Beta-hydroxybutyrate, mmol/L (ref, 0–0.9) | 1.9 | 3.9 | 5.8 |
| Albumin, g/dL (ref, 3.5–4.6) | 4 | 4.2 | 4.5 |
| pH | 7.44 | 7.38 | ND |
| Serum bicarbonate, mmol/L (ref, 20–26) | 28.6 | 30 | 26 |
Abbreviations: ND, not determined; BCE, bone collagen equivalents; PTHrP, parathyroid hormone related peptide.