INTRODUCTION. Dent disease is X-linked recessive proximal tubulopathy, due to
mutations in the CLCN5 gene. It is characterized by low molecular weight
proteinuria, hypercalciuria, nephrocalcinosis and progressive renal failure.
CASE OUTLINE. A seven-year-old boy was referred after endocrinological
examination where abdominal ultrasound showed nephrocalcinosis. There were
anamnestic data neither of oedema, macrohaematuria, nor polyuria or
hypertension. There were also no data of chronic renal failure in the family.
We determined: proteinuria (1.8 g/day), elevated urinary excretion of Beta 2
microglobulin, microscopic haematuria, hypercalciuria (8-10 mg/kg/day),
nephrocalcinosis, decreased tubular reabsorption phosphate (65%). Values of
growth hormone, parathormone on thyroid hormone were normal. Except
hypercalciuria, which was registered in the patient?s mother, all other
analyses performed in family members were betwen reference values. Diagnosis
was finalized by mutation analysis, which showed S244L substitution on CNCL5.
Mutation carrier was mother with normal phenotype. CONCLUSION. Dent disease
is rare X-linked nephrocalcinosis. Definitive diagnosis of this proximal
tubulopathy which leads to progressive renal damage is not possible without
evidence of gene mutation in renal chlorine channel.
From protein uptake to Dent disease: An overview of the CLCN5 gene