CLCN5

CLCN5 is a gene that encodes the protein chloride channel 5, which is a member of the CLC family of chloride channels and transporters. This protein is primarily expressed in the kidney and plays a crucial role in the reabsorption of chloride ions in the proximal tubules.

Function

The CLCN5 protein is involved in the regulation of chloride ion transport across cell membranes. It functions as an electrogenic antiporter, exchanging chloride ions for protons. This activity is essential for maintaining the proper ionic balance and pH within the kidney cells, which is critical for the reabsorption of various solutes and water.

Clinical Significance

Mutations in the CLCN5 gene are associated with Dent's disease, a rare X-linked recessive disorder characterized by low molecular weight proteinuria, hypercalciuria, nephrocalcinosis, and progressive renal failure. Patients with Dent's disease often present with symptoms such as kidney stones, bone demineralization, and renal tubular acidosis.

Pathophysiology

The mutations in CLCN5 disrupt the normal function of the chloride channel, leading to impaired reabsorption of filtered proteins and other solutes in the proximal tubules. This results in the characteristic features of Dent's disease, including proteinuria and hypercalciuria. The accumulation of calcium in the kidneys can lead to nephrocalcinosis and eventually to chronic kidney disease.

Diagnosis

The diagnosis of Dent's disease is typically based on clinical features, family history, and genetic testing to identify mutations in the CLCN5 gene. Urinalysis may reveal low molecular weight proteinuria, and imaging studies can detect nephrocalcinosis.

Treatment

There is currently no cure for Dent's disease, and treatment is primarily supportive. Management strategies include maintaining adequate hydration, using thiazide diuretics to reduce hypercalciuria, and monitoring and treating complications such as kidney stones and bone demineralization.

See Also

• Dent's disease
• Chloride channel
• Kidney
• Renal tubular acidosis
• Nephrocalcinosis

External Links

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