Distal renal tubular acidosis (RTA) is a biochemical syndrome as a deficiency of hydrogen in secretion by the distal tubule and collecting duct. Owing to the nature of the defect, hyperchloremic non-anion gap metabolic acidosis and high urine pH
despite
severe systemic acidosis is characterized.
Typical manifestations of distal RTA are growth retardation, rickets, polyuria and nephrocalcinosis.
We experienced a case of distal renal tubular acidosis in a 4 years old female child who complained of growth retardation and gait disturbance. She showed typical hyperchloremic non-anion gap metabolic acidosis and persistent high urine pH. In
radiographic examination. we found delayed bone age and severe rachitic changes of wrist, elbow, and knee as well as nephrocalcinosis. In ammonium chloride loading test, high urine pH persisted despite the lowering blood HCO3- concentration.
After alkali therapy, she is in well condition with excellent growth velocity and absence of rachitic changes.
|