DISTAL RENAL TUBULAR ACIDOSIS SCREENING BY URINARY ACIDIFICATION TESTING IN MEXICAN CHILDREN

作者：Guerra Hernandez Norma E^*; Ordaz Lopez Karen V; Escobar Perez Laura; Gomez Tenorio Circe; Garcia Nieto Victor M

来源：Revista de Investigacion Clinica-Clinical and Translational Investigation, 2015, 67(3): 191-198.

• Acidosis
• Distal renal tubular acidosis
• Nephrocalcinosis
• Proximal renal tubular acidosis
• Urinary acidification
• Urinary acidification test

Background: Primary distal renal tubular acidosis is a clinical disorder characterized by hyperchloremic metabolic acidosis, hypercalciuria, hypocitraturia, urinary acidification impairment, hypokalemia, metabolic bone disease, and nephrocalcinosis. Urinary acidification ability may be evaluated by an acidification test or maximum urinary pCO(2) assessment with alkaline urine. The maximum urinary pCO(2) test using acetazolamide and sodium bicarbonate is an easy test to confirm the lack of urine acidification in distal renal tubular acidosis in children. Objective: To determine the urinary acidification ability using the maximum urinary pCO(2) assessment in a group of children with a distal renal tubular acidosis diagnosis. Material and methods: Thirty children were evaluated (13 males and 17 females); 23 children had been diagnosed with distal renal tubular acidosis by other physicians and were under alkali treatment with potassium and sodium citrates (21) and bicarbonate (2), and five children were not under alkali treatment. Two children had been diagnosed with primary distal renal tubular acidosis by our medical group. The maximum urinary pCO(2) was determined by the oral intake of acetazolamide and sodium bicarbonate. Results: Two cases with primary distal renal tubular acidosis were found, and they had a history of dehydration episodes during infancy and showed hyperchloremic metabolic acidosis with hypokalemia. They also exhibited urine acidification impairment with furosemide and reduced urinary pCO(2) (< 60 mmHg), and the urine-blood pCO(2) gradient was reduced in both cases (< 30 mmHg). One of them developed bilateral sensorineural deafness, while the other showed severe hypocitraturia. One case of proximal or type 2 renal tubular acidosis with hyperaminoaciduria was identified. Twenty-eight children displayed normal urinary acidification and did not show signs of distal renal tubular acidosis. Conclusions: The urinary acidification test with furosemide and urinary pCO(2) assessment are reliable tests to identify the renal excretion of hydrogen ions (H+) and allow confirmation of the lack of urine acidification in distal renal tubular acidosis.

• 出版日期2015-6