From the Research
The ATP6V1B1 gene plays a crucial role in regulating acid-base balance in the body, and mutations in this gene can cause distal renal tubular acidosis with sensorineural deafness (dRTA), a condition characterized by the kidney's inability to properly acidify urine, leading to metabolic acidosis, growth retardation, rickets, nephrocalcinosis, and hearing loss. The ATP6V1B1 gene encodes the B1 subunit of the V-ATPase pump, which functions primarily in the kidney's collecting ducts and inner ear 1. According to the most recent study, heterozygous variants affecting Arg394 in the ATP6V1B1 gene are associated with a dominant disease mechanism, leading to dRTA with a lower prevalence of hearing loss compared to the recessive form 1.
Clinical Presentation and Treatment
Patients with ATP6V1B1 mutations typically present with:
- Metabolic acidosis
- Growth retardation
- Rickets
- Nephrocalcinosis
- Hearing loss Treatment involves alkali therapy, usually with potassium citrate or sodium bicarbonate at doses of 1-3 mEq/kg/day divided into multiple daily doses, adjusted based on blood pH monitoring 2, 3, 4, 5.
Importance of Early Diagnosis and Treatment
Early diagnosis and treatment are essential to prevent complications like kidney stones, bone disease, and growth impairment. The gene's critical role in maintaining proper pH balance explains why its dysfunction leads to systemic acid-base disturbances and hearing problems, as the same proton pump is vital for endolymph pH regulation in the inner ear 1.
Key Findings
- The ATP6V1B1 gene is crucial for regulating acid-base balance in the body
- Mutations in ATP6V1B1 can cause dRTA with sensorineural deafness
- Heterozygous variants affecting Arg394 are associated with a dominant disease mechanism
- Early diagnosis and treatment are essential to prevent complications
- Alkali therapy is the primary treatment for dRTA, with potassium citrate or sodium bicarbonate being the most commonly used medications 1.