Hereditary vitamin D-resistant rickets （HVDRR） is a rare autosomal recessive disorder characterized by severe rickets, hypocalcemia, hypophosphatemia, secondary hyperparathyroidism, and elevated alkaline phosphatase...Hereditary vitamin D-resistant rickets （HVDRR） is a rare autosomal recessive disorder characterized by severe rickets, hypocalcemia, hypophosphatemia, secondary hyperparathyroidism, and elevated alkaline phosphatase. This disorder is caused by homogeneous or heterogeneous mutations affecting the function of the vitamin D receptor （VDR）, which lead to complete or partial target organ resistance to the action of 1,25- dihydroxy vitamin D~ A non-consanguineous family of Chinese Han origin with one affected individual demonstrating HVDRR was recruited, with the proband evaluated clinically, biochemically and radiographically. To identify the presence of mutations in the VDR gene, all the exons and exon-intron junctions of the VDR gene from all family members were amplified using PCR and sequenced. The proband showed rickets, progressive alopecia, hypocalcemia, hypophosphatemia, secondary hyperparathyroidism, and elevated alkaline phosphatase. She also suffered from epilepsy, which is rarely seen in patients with HVDRR. Direct sequencing analysis revealed a homozygous missense mutation c.122G 〉 A （p.C41Y） in the VDR gene of the proband, which is located in the first zinc finger of the DNA-binding domain. Both parents had a normal phenotype and were found to be heterozygous for this mutation. We report a Chinese Han family with one individual affected with HVDRR. A homozygous missense mutation c.122G 〉 A （p.C41Y） in the VDR gene was found to be responsible for the patient＇s syndrome. In contrast to the results of treatment of HVDRR in other patients, our patient responded well to a supplement of oral calcium and a low dose of calcitriol.展开更多
Familial hypocalciuric hypercalcemia （FHH） is caused by inactivating mutations in the calcium-sensing receptor （CaSR） gene. The loss of function of CaSR presents with rickets as the predominant skeletal abnormalit...Familial hypocalciuric hypercalcemia （FHH） is caused by inactivating mutations in the calcium-sensing receptor （CaSR） gene. The loss of function of CaSR presents with rickets as the predominant skeletal abnormality in mice, but is rarely reported in humans. Here we report a case of a 16-year-old boy with FHH who presented with skeletal manifestations of rickets. To identify the possible pathogenic mutation, the patient was evaluated clinically, biochemically, and radiographicaUy. The patient and his family members were screened for genetic mutations. Physical examination revealed a pigeon breast deformity and X-ray examinations showed epiphyseal broadening, both of which indicate rickets. Biochemical tests also showed increased parathyroid hormone （PTH）, 1,25-dihydroxyvitamin D, and elevated ionized calcium. Based on these results, a diagnosis of FHH was suspected. Sequence analysis of the patient＇s CaSR gene revealed a new missense mutation （c.2279T 〉 A） in exon 7, leading to the damaging amino change （p.I760N） in the mature CaSR protein, confirming the diagnosis of ~H. Moreover, the skeletal abnormities may be related to but not limited to vitamin D abnormity. Elevated ~H levels and a rapid skeletal growth period in adolescence may have also contributed. Our study revealed that rickets-like features have a tendency to present atypically in FHH patients who have a mild vitamin D deficiency, and that CaSR mutations may have a partial role in the pathogenesis of skeletal deformities.展开更多
One of the major causes of congenital hypophosphatemic rickets is the X-linked hypophosphatemic rickets (XHR), due to a defect on PHEX gene. The XHR increases the renal elimination of phosphate, that condition leads a...One of the major causes of congenital hypophosphatemic rickets is the X-linked hypophosphatemic rickets (XHR), due to a defect on PHEX gene. The XHR increases the renal elimination of phosphate, that condition leads a defective mineralization of bones and also affects the growth in children. Clinical diagnosis should be suspected in children with signs of rickets and hypophosphatemia with normal calcium levels. We describe clinical characteristics and genetic results of four patients diagnosed and treated in our Nephrology Section. All patients have a “de novo” XHR as none familiars are affected. Early diagnosis should be suspected before the bone deformities have been submitted and the growth would have been impaired.展开更多
目的以一个临床表型为低血磷性佝偻病(hypophosphatemic rickets,HR)的家系为研究对象,通过全外显子组测序寻找该家系的致病变异基因,并分析变异的致病性。方法收集HR家系临床资料,进行生化检测。提取先证者DNA,进行临床全外显子组测序...目的以一个临床表型为低血磷性佝偻病(hypophosphatemic rickets,HR)的家系为研究对象,通过全外显子组测序寻找该家系的致病变异基因,并分析变异的致病性。方法收集HR家系临床资料,进行生化检测。提取先证者DNA,进行临床全外显子组测序,并针对可疑致病变异对家系所有成员进行PCR扩增,Sanger测序验证。预测变异的致病性及对蛋白质空间结构的影响。结果该家系共3代,先证者是一位26岁女性,先证者母亲、先证者及其儿子和女儿为患者,临床表现为O型腿、鸡胸、低磷血症,骨骼X线检查、生化检测、成纤维细胞生长因子23(fibroblast growth factor 23,FGF23)检测结果提示低血磷性佝偻病。临床全外显子组测序发现PHEX(NM_000444)c.2193dupT的插入移码杂合变异,该变异可导致编码第732位的天冬酰胺变异为终止密码子(p.N732*),从而出现了蛋白质截短。先证者的母亲、儿子及女儿PHEX基因均存在该变异。根据美国医学遗传学与基因组学学会(American College of Medical Genetics and Genomics,ACMG)对变异的分类标准,分级为可能致病性变异。经查阅文献及查找人类基因突变数据库,该变异均未被报道或收录。结论本研究发现了一个PHEX新致病变异,为该家系的临床诊断和治疗及遗传咨询提供了实验依据。展开更多
Background Hypophosphatemic rickets/osteomalacia is a group of diseases characterised by defective mineralization of bone due to hypophosphatemia and low 1,25-dihydroxy vitamin D. To explore the role of fibroblast gro...Background Hypophosphatemic rickets/osteomalacia is a group of diseases characterised by defective mineralization of bone due to hypophosphatemia and low 1,25-dihydroxy vitamin D. To explore the role of fibroblast growth factor 23 （FGF-23） in the regulation of phosphate homeostasis, we measured the circulating concentrations of this growth factor in healthy individuals and in patients with hypophosphatemic rickets/osteomalacia. Methods Nineteen patients with hypophosphatemic rickets/osteomalacia were included in hypophosphatemic group （HP, 12 female and 7 male, mean age was 30 years）, and 19 healthy age-matched individuals served as the control group. Full length FGF-23 fragments were measured by two-site enzyme-linked immunosorbent assay.Results Mean FGF-23 concentrations were significantly higher in the HP group （（87.4±43.6） pg/ml） compared with the control group （（19.2±6.16） pg/ml; P 〈0.001）. In 1 patient with tumour-induced osteomalacia, serum FGF-23 concentrations were 84.1 pg/ml; these concentrations were normalized 2 hours after a hemangiopericytoma resection （7.8 pg/ml）. Subsequently, serum 1,25（OH）2 vitamin D3 concentrations significantly increased from 21.3 pg/ml to 89.3 pg/ml, and serum phosphorus levels were normalized. Conclusions Serum FGF-23 concentrations were markedly elevated in patients with hypophosphatemic rickets. FGF-23 plays an important role in the pathogenesis of hypophosphatemic rickets/osteomalacia.展开更多
Hypophosphatemic vitamin D-resistant rickets or X-linked hypophosphatemia （XLH） is a rare hereditary metabolic disease manifesting marked hypophosphatemia, short stature and rickets. Its prevalence is approximately ...Hypophosphatemic vitamin D-resistant rickets or X-linked hypophosphatemia （XLH） is a rare hereditary metabolic disease manifesting marked hypophosphatemia, short stature and rickets. Its prevalence is approximately 1 in 20 000. Except early exfoliation of the teeth, there are a few oral findings of XLH described in China. Here we present two cases in one family.展开更多
基金supported by a grant from The Ministry of Science and Technology of the People’s Republic of China(National Science and Technology Major Projects for "Major New Drugs Innovation and Development" 2008ZX09312-016)National Natural Science Foundation of China (no.81070687 and 81170805)+2 种基金Beijing Natural Science Foundation (no.7121012)Scientific Research Foundation of Beijing Medical Development (no.2007-3029)National Key Program of Clinical Science (WBYZ2011-873)
文摘Hereditary vitamin D-resistant rickets （HVDRR） is a rare autosomal recessive disorder characterized by severe rickets, hypocalcemia, hypophosphatemia, secondary hyperparathyroidism, and elevated alkaline phosphatase. This disorder is caused by homogeneous or heterogeneous mutations affecting the function of the vitamin D receptor （VDR）, which lead to complete or partial target organ resistance to the action of 1,25- dihydroxy vitamin D~ A non-consanguineous family of Chinese Han origin with one affected individual demonstrating HVDRR was recruited, with the proband evaluated clinically, biochemically and radiographically. To identify the presence of mutations in the VDR gene, all the exons and exon-intron junctions of the VDR gene from all family members were amplified using PCR and sequenced. The proband showed rickets, progressive alopecia, hypocalcemia, hypophosphatemia, secondary hyperparathyroidism, and elevated alkaline phosphatase. She also suffered from epilepsy, which is rarely seen in patients with HVDRR. Direct sequencing analysis revealed a homozygous missense mutation c.122G 〉 A （p.C41Y） in the VDR gene of the proband, which is located in the first zinc finger of the DNA-binding domain. Both parents had a normal phenotype and were found to be heterozygous for this mutation. We report a Chinese Han family with one individual affected with HVDRR. A homozygous missense mutation c.122G 〉 A （p.C41Y） in the VDR gene was found to be responsible for the patient＇s syndrome. In contrast to the results of treatment of HVDRR in other patients, our patient responded well to a supplement of oral calcium and a low dose of calcitriol.
基金supported by the National Natural Science Foundation of China(nos.81070687 and 81170805)Beijing Natural Science Foundation(no.7121012)+2 种基金Ministry of Science and Technology of the People’s Republic of China(National Science and Technology Major Projects for‘Major New Drugs Innovation and Development 2008ZX09312-016)Scientific Research Foundation of Beijing Medical Development(no.2007-3029)National Key Program of Clinical Science(WBYZ2011-873)
文摘Familial hypocalciuric hypercalcemia （FHH） is caused by inactivating mutations in the calcium-sensing receptor （CaSR） gene. The loss of function of CaSR presents with rickets as the predominant skeletal abnormality in mice, but is rarely reported in humans. Here we report a case of a 16-year-old boy with FHH who presented with skeletal manifestations of rickets. To identify the possible pathogenic mutation, the patient was evaluated clinically, biochemically, and radiographicaUy. The patient and his family members were screened for genetic mutations. Physical examination revealed a pigeon breast deformity and X-ray examinations showed epiphyseal broadening, both of which indicate rickets. Biochemical tests also showed increased parathyroid hormone （PTH）, 1,25-dihydroxyvitamin D, and elevated ionized calcium. Based on these results, a diagnosis of FHH was suspected. Sequence analysis of the patient＇s CaSR gene revealed a new missense mutation （c.2279T 〉 A） in exon 7, leading to the damaging amino change （p.I760N） in the mature CaSR protein, confirming the diagnosis of ~H. Moreover, the skeletal abnormities may be related to but not limited to vitamin D abnormity. Elevated ~H levels and a rapid skeletal growth period in adolescence may have also contributed. Our study revealed that rickets-like features have a tendency to present atypically in FHH patients who have a mild vitamin D deficiency, and that CaSR mutations may have a partial role in the pathogenesis of skeletal deformities.
文摘One of the major causes of congenital hypophosphatemic rickets is the X-linked hypophosphatemic rickets (XHR), due to a defect on PHEX gene. The XHR increases the renal elimination of phosphate, that condition leads a defective mineralization of bones and also affects the growth in children. Clinical diagnosis should be suspected in children with signs of rickets and hypophosphatemia with normal calcium levels. We describe clinical characteristics and genetic results of four patients diagnosed and treated in our Nephrology Section. All patients have a “de novo” XHR as none familiars are affected. Early diagnosis should be suspected before the bone deformities have been submitted and the growth would have been impaired.
文摘目的以一个临床表型为低血磷性佝偻病(hypophosphatemic rickets,HR)的家系为研究对象,通过全外显子组测序寻找该家系的致病变异基因,并分析变异的致病性。方法收集HR家系临床资料,进行生化检测。提取先证者DNA,进行临床全外显子组测序,并针对可疑致病变异对家系所有成员进行PCR扩增,Sanger测序验证。预测变异的致病性及对蛋白质空间结构的影响。结果该家系共3代,先证者是一位26岁女性,先证者母亲、先证者及其儿子和女儿为患者,临床表现为O型腿、鸡胸、低磷血症,骨骼X线检查、生化检测、成纤维细胞生长因子23(fibroblast growth factor 23,FGF23)检测结果提示低血磷性佝偻病。临床全外显子组测序发现PHEX(NM_000444)c.2193dupT的插入移码杂合变异,该变异可导致编码第732位的天冬酰胺变异为终止密码子(p.N732*),从而出现了蛋白质截短。先证者的母亲、儿子及女儿PHEX基因均存在该变异。根据美国医学遗传学与基因组学学会(American College of Medical Genetics and Genomics,ACMG)对变异的分类标准,分级为可能致病性变异。经查阅文献及查找人类基因突变数据库,该变异均未被报道或收录。结论本研究发现了一个PHEX新致病变异,为该家系的临床诊断和治疗及遗传咨询提供了实验依据。
基金This study was supported by National Natural Science Foundation of China （NSFC） （No. 30370781） and Doctoral Fund of Ministry of Education of China （No. 20040023055） The authors state that there are no conflicts of interest in this study.
文摘Background Hypophosphatemic rickets/osteomalacia is a group of diseases characterised by defective mineralization of bone due to hypophosphatemia and low 1,25-dihydroxy vitamin D. To explore the role of fibroblast growth factor 23 （FGF-23） in the regulation of phosphate homeostasis, we measured the circulating concentrations of this growth factor in healthy individuals and in patients with hypophosphatemic rickets/osteomalacia. Methods Nineteen patients with hypophosphatemic rickets/osteomalacia were included in hypophosphatemic group （HP, 12 female and 7 male, mean age was 30 years）, and 19 healthy age-matched individuals served as the control group. Full length FGF-23 fragments were measured by two-site enzyme-linked immunosorbent assay.Results Mean FGF-23 concentrations were significantly higher in the HP group （（87.4±43.6） pg/ml） compared with the control group （（19.2±6.16） pg/ml; P 〈0.001）. In 1 patient with tumour-induced osteomalacia, serum FGF-23 concentrations were 84.1 pg/ml; these concentrations were normalized 2 hours after a hemangiopericytoma resection （7.8 pg/ml）. Subsequently, serum 1,25（OH）2 vitamin D3 concentrations significantly increased from 21.3 pg/ml to 89.3 pg/ml, and serum phosphorus levels were normalized. Conclusions Serum FGF-23 concentrations were markedly elevated in patients with hypophosphatemic rickets. FGF-23 plays an important role in the pathogenesis of hypophosphatemic rickets/osteomalacia.
文摘Hypophosphatemic vitamin D-resistant rickets or X-linked hypophosphatemia （XLH） is a rare hereditary metabolic disease manifesting marked hypophosphatemia, short stature and rickets. Its prevalence is approximately 1 in 20 000. Except early exfoliation of the teeth, there are a few oral findings of XLH described in China. Here we present two cases in one family.
