Reference Center for Inborn Errors of Metabolism, Pediatric Unit, University Hospital of Nancy, Nancy, France.
INSERM UMR_S 1256, Nutrition, Genetics, and Environmental Risk Exposure (NGERE), Faculty of Medicine of Nancy, University of Lorraine, Nancy, France.
Calcif Tissue Int. 2020 Aug;107(2):191-194. doi: 10.1007/s00223-020-00704-4. Epub 2020 May 19.
Vitamin D-dependent rickets type 1B (VDDR1B) is an autosomal semidominant genetic disorder caused by a deficiency in CYP2R1, which encodes vitamin D 25-hydroxylase, an enzyme that plays a crucial role in the conversion of vitamin D to 25-dihydroxyvitamin D. VDDR1B is a severe form of rickets that occurs during infancy and which is responsive to 25-OH vitamin D supplementation. We studied three adult patients from a multi-consanguineous family with VDDR1B. They have been diagnosed with pseudo-nutritional rickets and treated during their adolescence with 25-OH vitamin D. These patients stopped their treatments at the end of adolescence and were contacted 14 to 17 years later when VDDR1B diagnosis was carried out in their niece and nephews. These three patients had undetectable 25-OH vitamin D, but normal levels of plasma 1-25(OH) vitamin D. All patients had a hip bone mineral density and a normal vertebral despite osteoarthritis degenerative lesions which may impact BMD evaluation. These findings show that vitamin D supplementation has a questionable effect, if any, for osteoporosis prevention in adulthood in contrast to its crucial importance during infancy and adolescence.
维生素 D 依赖性佝偻病 1B 型（VDDR1B）是一种常染色体半显性遗传疾病，由 CYP2R1 缺乏引起，CYP2R1 编码维生素 D25-羟化酶，该酶在维生素 D 向 25-二羟维生素 D 的转化中起着关键作用。VDDR1B 是一种严重的佝偻病，发生在婴儿期，对 25-羟维生素 D 补充有反应。我们研究了来自一个多近亲结婚家族的三名成年 VDDR1B 患者。他们被诊断为假性营养性佝偻病，并在青春期接受 25-羟维生素 D 治疗。这些患者在青春期结束时停止治疗，14 至 17 年后，他们的侄女和侄子被诊断出患有 VDDR1B。这三名患者的 25-羟维生素 D 检测不到，但血浆 1-25（OH）维生素 D 水平正常。所有患者的髋骨矿物质密度和正常的椎体，尽管有骨关节炎退行性病变，这可能会影响 BMD 评估。这些发现表明，维生素 D 补充对成年期骨质疏松症的预防几乎没有作用，而在婴儿期和青春期则至关重要。
