Inherited Defects in Distal Tubular Acidification

Excerpt

The pathognomonic defect of classic, or type I, renal tubular acidosis is an inability of the distal tubule to maintain the normal hydrogen ion gradient between tubular urine and plasma, and so secrete a maximally acid urine (1, 2). The full syndrome includes, by definition, a systemic acidosis, but the development of acidosis depends on many factors, including the severity of the acidification defect, urinary excretion of hydrogen ion acceptors such as ammonia and phosphate, and the load of endogenously produced hydrogen ion requiring excretion. As might be expected, some patients do not have systemic acidosis despite the presence of