Dent disease is a rare X-linked tubulopathy characterized by low molecular weight proteinuria, hypercalciuria, nephrocalcinosis and/or nephrolithiasis, progressive renal failure, and variable manifestations of other proximal tubule dysfunctions. It often progresses over a few decades to chronic renal insufficiency, and therefore molecular characterization is important to allow appropriate genetic counseling. Two genetic subtypes have been described to date: Dent disease 1 is caused by mutations of the CLCN5 gene, coding for the chloride/proton exchanger ClC-5; and Dent disease 2 by mutations of the OCRL gene, coding for the inositol polyphosphate 5-phosphatase OCRL-1.
View Article and Find Full Text PDFThe etiologies of early onset nephrocalcinosis in consanguineous families include five major inherited recessive disorders: primary hyperoxaluria (PH), familial hypomagnesemia with hypercalciuria and nephrocalcinosis (FHHNC), distal renal tubular acidosis (dRTA), hereditary hypophosphatemic rickets with hypercalciuria (HHRH) and antenatal Bartter syndrome. In this paper, we describe two girls from consanguineous parents with early onset nephrocalcinosis. Based on both clinical and biochemical assessment in combination with molecular genetics, we have shown that the etiology of nephrocalcinosis is different in each girl: one had FHHNC and her sister had dRTA.
View Article and Find Full Text PDFMutations in the ATP6V1B1 and ATP6V0A4 genes, encoding subunits B1 and 4 of apical H(+) ATPase, cause recessive forms of distal renal tubular acidosis (dRTA). ATP6V1B mutations have been associated with early sensorineural hearing loss (SNHL), whereas ATP6V0A4 mutations are classically associated with either late-onset SNHL or normal hearing. The phenotype and genotype of 39 new kindreds with recessive dRTA, 18 of whom were consanguineous, were assessed.
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