Distal renal tubular acidosis (distal acidosis primary, familial, dRTA, type 1 RTA) is a disorder that affects the kidneys and results in too much acid in the blood stream. Normally, the kidneys filter excess fluid and waste from the body through the urine, however, in individuals with distal renal (kidney) tubular acidosis, the kidneys are unable to remove enough acid and therefore acid levels in the blood become are too high. When the blood has high levels of acid, it is called metabolic acidosis. Symptoms of metabolic acidosis include confusion, fatigue, kidney stones, muscle weakness, and increased breathing rate. Other symptoms include a deficiency in vitamins leading to soft and weak bones (nephrocalcinosis, osteomalacia, rickets), decreased urine output, muscle cramps, back or abdominal pain, and an irregular heartbeat. Distal renal tubular acidosis can be complete or incomplete depending upon whether or not the person develops symptoms of metabolic acidosis or not despite the decrease in kidney function. In some individuals, blood cell abnormalities are also present such as hemolytic anemia. Distal renal tubular acidosis is diagnosed through a blood or urine test. People with this condition usually have a good outlook and can manage the symptoms well if they take prescribed medications. If you or a family member has been diagnosed with renal tubular acidosis, talk with your doctor and specialists about the most current treatment options.
Distal renal tubular acidosis can be inherited either in an autosomal dominant manner or autosomal recessive manner. The recessive form is more likely to have the associated blood cell abnormalities. This condition is most common in Southeast Asia, especially Thailand. A genetic counselor can provide an understanding of the underlying genetic causes as well as the recurrence risks.