The Excretion of Acid in Unilateral Renal Disease in Man*

Abstract

The excretion of acid by the diseased kidney was studied in unilateral renal disease in man by comparing the diseased kidney with the "normal" kidney. Eight patients with parenchymal disease and 4 with stenosis of the main renal artery were examined. In the patients with parenchymal renal disease (pyelonephritis, infarcation atrophy) the excretion of ammonium and titratable acid in the diseased kidney was decreased in proportion to the decrease in functioning nephron mass as estimated from glomerular filtration rate (GFR). Even after ammonium chloride loading urine pH and ammonium and titratable acid excretion per unit of GFR remained similar in the diseased and the normal kidneys. Hence, in the diseases studied no specific tubular defect could be demonstrated for either the secretion of hydrogens ions or the production of ammonia. The proportionality between GFR and the tubular capacity to excrete acid observed in unilateral renal artery stenosis in whom the urine from the affected kidney was acidified to a greater extent than that from the contralateral kidney.