维生素D依赖性佝偻病IA型两例报告

Vitamin D-dependent rickets type IA:two cases report

回顾性分析2017年7月至2019年9月在深圳市儿童医院诊断为维生素D依赖性佝偻病IA型(vitamin D-dependent rickets IA,VDDR-IA)2例患儿的症状、体征、实验室检查(包括1α-羟化酶编码基因CYP27B1检测结果)、影像学资料及随访情况,并进行文献复习.两例患儿女性、男性各1例,分别于11月龄和18月龄起病,临床表现为佝偻病,25羟维生素D(25-hydroxyvitamin D,25OHD)正常或轻度升高,常规维生素D治疗无效,其中1例股骨骨折迁延2年余不愈,经CYP27B1基因测序分析发现两例患者1例为c.1319_1325dupCCCACCC纯合突变、1例为[c.1319_1325dupCCCACCC]+[c.1358G>A]复合杂合突变,确诊为VDDR-IA,予口服骨化三醇及钙剂治疗,分别随诊35个月、22个月,患儿症状、体征好转,骨折愈合,呈现身高追赶.当佝偻病发病年龄不典型,常规维生素D治疗无效,25OHD不低时,需警惕VDDR-IA,并行CYP27B1基因检测,注意c.1319_1325dupCCCACCC突变.

To analyze symptoms,signs,and laboratory datas,including 1 alpha-hydroxylase coding gene(CYP27B1)sequencing analysis,radiological findings,and follow-up data retrospectively in two patients with vitamin D-dependent rickets type IA(VDDR-ⅠA)in Shenzhen Children s Hospital from July 2017 to September 2019.One female and one male patient(11 and 18 months of age onset),had manifestations of rickets,normal or slightly elevated 25OHD,and routine vitamin D treatment is ineffective.One case of femoral fracture did not heal for more than 2 years.CYP27B1 gene sequencing identified that 1 case with c.1319_1325dupCCCACCC homozygous mutations,1 case with[c.1319_1325dupCCCACCC]+[c.1358 G>A]compound heterozygous mutations,both were diagnosed with VDDR-ⅠA and given calcitriol and calcium.After 35 and 22 months of fol-low-up,the symptoms and signs of patients were improved,the fracture healed,and both showed height catch-up.When onset age of rickets is atypical,and conventional vitamin D treatment is ineffective,without low 25OHD,we need to be vigilant about VDDR-ⅠA and sequence CYP27B1 gene,especially paying attention to c.1319_1325dupCCCACCC mutation.