A new classification for renal defects in net acid excretion
| Autor: | Kamel S. Kamel, Sang Whay Kooh, J. Williamson Balfe, Peter D. Yorgin, Luis F. Briceno, Marta I. Sanchez, Mitchell L. Halperin, Luis Brenes |
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| Rok vydání: | 1997 |
| Předmět: |
Adult
Male medicine.medical_specialty Renal function Nephron Kidney Renal tubular acidosis Excretion Chlorides Internal medicine medicine Humans Child Acidosis business.industry Metabolic acidosis Acidosis Renal Tubular Hydrogen-Ion Concentration medicine.disease Quaternary Ammonium Compounds Bicarbonates medicine.anatomical_structure Endocrinology Nephrology Female medicine.symptom Net acid excretion business |
| Zdroj: | American journal of kidney diseases : the official journal of the National Kidney Foundation. 29(1) |
| ISSN: | 0272-6386 |
| Popis: | The traditional classification of the group of disorders called renal tubular acidosis (RTA) into proximal and distal subclasses is based on which nephron segment is thought to have an abnormal function. Nevertheless, such a distinction may not be correct and also does not characterize the pathophysiology of the renal acidosis in each patient. In this article, we propose an alternative classification, one that is based on the component of net acid excretion that is abnormal. We also suggest expanding the definition of net acid excretion to include a term that describes the renal handling of metabolizable organic anions because their loss in the urine represents the loss of "potential bicarbonate." Because a low rate of excretion of ammonium (NH4+) is present in patients with both distal and isolated proximal RTA, our initial clinical step in patients with hyperchloremic metabolic acidosis (HCMA) is to evaluate the rate of excretion of NH4+. The basis for a low rate of excretion of NH4+ is shown by examining the urine pH. If the urine pH is low, further studies are performed to determine why the availability of NH3 is low; if the urine pH is high, further investigations are initiated to examine if the defect in H+ secretion involves the proximal or the distal nephron. Conversely, if the rate of excretion of NH4+ is high in a patient with HCMA, a component of the degree of acidosis could be attributable to a high rate of excretion of metabolizable organic anions. Case examples are provided to illustrate the approach and its implications for future molecular studies. |
| Databáze: | OpenAIRE |
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