A three-year clinical investigation of a Chinese child with craniometaphyseal dysplasia caused by a mutated ANKH gene

Table 1 Blood test results after low-calcium diet

Age	17 mo	20 mo	25 mo	2 yr and 7 mo	4 yr and 2 mo	Reference value (0-18 years old)
Parathyroid hormone (pmol/L)	NA	3.48	3.94	4.61	3.72	1.58-6.83
Serum osteocalcin (ng/mL)	NA	95	166	60	33. 34	14-46
Combined β-CTX (ng/mL)	NA	1.76	4.37	1.30	1.09	0.04-0.78
25-hydroxyvitamin D (ng/mL)	NA	22. 3	29.67	26.78	24.66	30-100
Serum alkaline phosphatase (U/L)	884	673	642	243	362	104-345 (1-3 years old)93-309 (4-6 years old)
Calcium (mmol/L)	2.44	2.43	2.30	2.18	2.37	2.2-2.75
Phosphorus (mmol/L)	1.67	1.36	1.5	1.16	1.20	1-2.15 (1m-3 years old), 0.84-1.85 (> 4 years old)
5’-Nucleotidase (U/L)	3	2	4	3	3	0-11

β-CTX: Beta C-terminal telopeptide of type I collagen; NA: Not available.