Hasani-Ranjbar Shirin, Amoli Mahsa M, Ebrahim-Habibi Azadeh, Dehghan Ehsan, Soltani Akbar, Amiri Parvin, Larijani Bagher
Tehran University of Medical Sciences, Endocrinology and Metabolism Research Institute, Tehran, Iran.
J Clin Res Pediatr Endocrinol. 2012 Jun;4(2):89-93. doi: 10.4274/jcrpe.601.
Hereditary hypophosphatemic rickets with hypercalciuria (HHRH) is an autosomal recessive form of hypophosphatemia with hyperphosphaturia, hypercalciuria, and hypercalcemia. In two reports on six affected kindreds with HHRH, the disease was mapped to chromosome 9q34, which contains the SLC34A3 gene that encodes the renal type 2c sodium-phosphate cotransporter. Our objective was to define the clinical course of these cases in a family with HHRH and to screen for SLC34A3 gene in order to determine whether these mutations are responsible for HHRH.
After clinical and biochemical evaluations, the entire SLC34A3 gene was screened using PCR amplification followed by direct sequencing technique. In this paper, we describe a new kindred with HHRH and a case of progressive and complicated HHRH presenting at age 27 years.
We found 101-bp deletion in intron 9 of the SLC34A3 gene. The index patient was homozygous for this mutation which has been previously reported in a Caucasian population. This is the first report for presence of SLC34A3 intron 9 deletion in an Iranian population.
These data showed that HHRH can be easily missed or underdiagnosed. Genetic evaluation of patients with familial hypercalciuria, hypophosphatemia and nephrolithiasis is needed for further information on the prevalence and management of this rare disorder.
遗传性低磷血症伴高钙尿症（HHRH）是一种常染色体隐性形式的低磷血症，伴有高磷尿症、高钙尿症和高钙血症。在两篇关于六个患HHRH家系的报告中，该疾病被定位到9号染色体长臂3区4带，该区域包含编码肾2c型钠磷协同转运蛋白的SLC34A3基因。我们的目的是明确一个HHRH家系中这些病例的临床病程，并筛查SLC34A3基因，以确定这些突变是否是HHRH的病因。
在进行临床和生化评估后，采用聚合酶链反应（PCR）扩增及直接测序技术对整个SLC34A3基因进行筛查。在本文中，我们描述了一个新的HHRH家系以及一例27岁时出现的进行性复杂性HHRH病例。
我们在SLC34A3基因的内含子9中发现了101个碱基对的缺失。先证者对此突变呈纯合状态，该突变先前已在白种人群中报道过。这是伊朗人群中存在SLC34A3内含子9缺失的首次报告。
这些数据表明，HHRH很容易被漏诊或诊断不足。对于家族性高钙尿症、低磷血症和肾结石患者，需要进行基因评估，以获取关于这种罕见疾病的患病率和治疗的更多信息。
