CLINICAL CASE: DENT DISEASE IN A CHILD

The article presents a clinical case of an extremely rare orphan pathology of the kidneys: Dent’s disease (DD). It is a rare X-linked recessive proximal tubulopathy characterized by low molecular weight (LMW) proteinuria, hypercalciuria, nephrolithiasis, and slowly progressive renal failure. According to the few literature data, 30-80% of male patients have progression of renal failure to the terminal stage at the age of 30-50 years. A little over 15 years ago, Dent’s disease was not diagnosed in Russia, and the pathology was often described as nephrotic syndrome due to high proteinuria. According to the limited literature data, 30-80% of male patients experience progression of renal failure to the terminal stage at the age of 30-50 years. The question of hereditary kidney pathology arises if a child has urinary syndrome: increased levels of albumin, red blood cells, leukocytes, and cylindruria in the urine. Patients may also be short, but this is more common with Dent’s disease type 2. Diagnosis of congenital and hereditary kidney diseases, when they are not accompanied by bone or other external symptoms, is quite difficult. In addition, when the skeletal system is affected, Dent’s disease is often confused with hypophosphatemic rickets. To confirm the diagnosis of Dent’s disease, a molecular genetic study is necessary. Treatment is mainly aimed at preventing stone formation. Dent’s disease was first described by C.E. Dent and M. Friedman in 1964. In most cases, the disease is caused by mutations in the CLCN5 gene (type 1 Dent’s disease) and the OCRL1 gene (type 2 Dent’s disease). Due to the clinical heterogeneity of this disease, the epidemiology is unknown. Around the world, about 250 families with this pathology have been described. Many phenotypic variants of Dent’s disease are described as a separate entity, for example, X-linked recessive nephrolithiasis with renal failure, X-linked recessive hypophosphatemic rickets, familial idiopathic low-weight proteinuria (LMW) with hypercalciuria in the Japanese population. Early diagnosis of Dent’s disease is problematic; detection of low molecular weight proteinuria is not available in every laboratory, and it is not always possible to trace a genetic connection. Therefore, the fact of prolonged urinary syndrome in children, especially accompanied by a family predisposition to renal pathology, should always be alarming.

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