PDF(Pubmed)
Abstract：
Monogenic forms of rickets are being increasingly recognized. However, vitamin D-dependent rickets 1b (VDDR1b) due to CYP2R1 gene mutation is exceedingly rare. We report a 4.5-year-old girl and her younger sibling who presented with clinical, radiological, and biochemical features suggestive of nutritional rickets that did not resolve despite repeated therapeutic doses of vitamin D3. This led to evaluation for resistant rickets, which revealed a novel homozygous CYP2R1 c.50_51insTCGGCGGCGC; p.Leu18ArgfsTer79 variant in the affected siblings. The children were treated with oral calcium and cholecalciferol, dose titrated to maintain serum alkaline phosphatase, 25 hydroxy vitamin D, and parathyroid hormone levels in the normal range, with good clinical and radiological response. This case highlights the importance of genetic evaluation in patients with suspected nutritional rickets who have a family history of similar illness and require higher than usual doses of vitamin D for healing or relapse on stopping treatment. To the best of our knowledge this is the first case of VDDR1b reported from Asia.
摘要：
日益认识到单基因形式的病。然而,由于CYP2R1基因突变导致的维生素D依赖性病1b（VDDR1b）极为罕见。我们报告了一个4.5岁的女孩和她的弟弟妹妹，放射学,和生化特征提示尽管反复服用维生素D3治疗剂量,但仍未消退的营养性病。这导致了对抗病的评估，揭示了受影响兄弟姐妹中的新型纯合CYP2R1c.50_51insTCGGCGGCGC；p.Leu18ArgfsTer79变体。儿童口服钙和胆钙化醇治疗，剂量滴定以维持血清碱性磷酸酶，25羟基维生素D,甲状旁腺激素水平在正常范围内，具有良好的临床和放射学反应。该病例强调了遗传评估对于有类似疾病家族史并且需要高于常规剂量的维生素D以治愈或在停止治疗后复发的疑似营养病患者的重要性。据我们所知，这是亚洲报道的第一例VDDR1b病例。
