PARTIAL DEFECT OF RENAL ACIDIFICATION CAP ACITY IN PATIENTS WITH RENAL LITHIASIS

Renal acidification capacity was studies in 35 adult patients with a h istory of 1 or more episodes of renal lithiasis. All of the patients' urinary pH was lower than 5.35 in the acidification test performed wit h ammonium chloride as well as that performed after furosemide adminis tration. The patients were divided into two groups: One with hypercalc iuria, the other without. Although urinary pH was lowered adequately, the total excretion of hydrogen ions in both tests was lower for both groups, as compared with controls. In addition, significatly lower val ues of plasma bicarbonate were found in both groups. Our results showe d that in patients with renal lithiasis there was partial acidificatio n defect, despite adequate lowering of urinary pH, and that these find ings were independent of the metabolic etiology of the lithiasis.