Abstract
Renal tubular acidosis (RTA) comprises a group of disorders characterized by low capacity for net acid excretion and persistent hyperchloremic metabolic acidosis, despite preserved glomerular filtration rate. RTA are classified into chiefly three types (1, 2 and 4) based on pathophysiology and clinical and laboratory characteristics. Most patients have primary RTA that presents in infancy with polyuria, growth retardation, rickets and/or hypotonia. Diagnosis requires careful evaluation, including exclusion of other entities that can cause acidosis. A variety of tests, administered stepwise, are useful for the diagnosis and characterization of RTA. A genetic or acquired basis can be determined in majority of patients through focused evaluation. Management involves correction of acidosis and dyselectrolytemia; patients with proximal RTA with Fanconi syndrome and rickets require additional supplements of phosphate and vitamin D.
Similar content being viewed by others
References
Soriano JR. Renal tubular acidosis: the clinical entity. J Am Soc Nephrol. 2002;13:2160–70.
Guo YM, Liu Y, Liu M, et al. Na+/HCO3− cotransporter NBCn2 mediates HCO3−reclamation in the apical membrane of renal proximal tubules. J Am Soc Nephrol. 2017;28:2409–19.
Curthoys NP, Moe OW. Proximal tubule function and response to acidosis. Clin J Am Soc Nephrol. 2014;9:1627–38.
Wagner C, Devuyst O, Bourgeois S, Mohebbi N. Regulated acid–base transport in the collecting duct. Eur J Phys. 2009;458:137–56.
Chambrey R, Trepiccione F. Relative roles of principal and intercalated cells in the regulation of sodium balance and blood pressure. Curr Hypertens Rep. 2015;17:538.
Weiner ID, Verlander JW. Ammonia transporters and their role in acid-base balance. Physiol Rev. 2017;97:465–94.
Mioni R, Mioni G. Titratable acidity: a Pitts concept revisited. Scand J Clin Lab Invest. 2014;74:408–13.
Trepiccione F, Prosperi F, de la Motte LR, et al. New findings on the pathogenesis of distal renal tubular acidosis. Kidney Dis (Basel). 2017;3:98–105.
Foreman JW. Fanconi syndrome. Pediatr Clin N Am. 2019;66:159–67.
Cherqui S, Courtoy PJ. The renal Fanconi syndrome in cystinosis: pathogenic insights and therapeutic perspectives. Nat Rev Nephrol. 2017;13:115–31.
Ehlayel AM, Copelovitch L. Update on dent disease. Pediatr Clin N Am. 2019;66:169–78.
Rungroj N, Nettuwakul C, Sawasdee N, et al. Distal renal tubular acidosis caused by tryptophan-aspartate repeat domain 72 (WDR72) mutations. Clin Genet. 2018;94:409–18.
Jobst-Schwan T, Klämbt V, Tarsio M, et al. Whole exome sequencing identified ATP6V1C2 as a novel candidate gene for recessive distal renal tubular acidosis. Kidney Int. 2020;97:567–79.
Enerbäck S, Nilsson D, Edwards N, et al. Acidosis and deafness in patients with recessive mutations in FOXI1. J Am Soc Nephrol. 2018;29:1041–8.
Batlle D, Arruda J. Hyperkalemic forms of renal tubular acidosis: clinical and pathophysiological aspects. Adv Chronic Kidney Dis. 2018;25:321–33.
Batlle D, Moorthi KM, Schlueter W, Kurtzman N. Distal renal tubular acidosis and the potassium enigma. Semin Nephrol. 2006;26:471–8.
Strife CF, Clardy CW, Varade WS, Prada AL, Waldo FB. Urine-to-blood carbon dioxide tension gradient and maximal depression of urinary pH to distinguish rate-dependent from classic distal renal tubular acidosis in children. J Pediatr. 1993;122:60–5.
Kim S, Lee JW, Park J, et al. The urine-blood PCO2 gradient as a diagnostic index of H+-ATPase defect distal renal tubular acidosis. Kidney Int. 2004;66:761–7.
Alexander RT, Cordat E, Chambrey R, Dimke H, Eladari D. Acidosis and urinary calcium excretion: insights from genetic disorders. J Am Soc Nephrol. 2016;27:3511–20.
Hamm LL. Renal handling of citrate. Kidney Int. 1990;38:728–35.
Fuster DG, Moe OW. Incomplete distal renal tubular acidosis and kidney stones. Adv Chronic Kidney Dis. 2018;25:366–74.
Alonso-Varela M, Gil-Peña H, Santos F. Incomplete distal renal tubular acidosis in children. Acta Paediatr. 2020. https://doi.org/10.1111/apa.15269.
Shah GN, Bonapace G, Hu PY, Strisciuglio P, Sly WS. Carbonic anhydrase II deficiency syndrome (osteopetrosis with renal tubular acidosis and brain calcification): novel mutations in CA2 identified by direct sequencing expand the opportunity for genotype-phenotype correlation. Hum Mutat. 2004;24:272.
Gupta S, Gao JJ, Emmett M, Fenves AZ. Topiramate and metabolic acidosis: an evolving story. Hosp Pract (1995). 2017;45:192–5.
Besouw MTP, Bienias M, Walsh P, et al. Clinical and molecular aspects of distal renal tubular acidosis in children. Pediatr Nephrol. 2017;32:987–96.
Gopal-Kothandapani JS, Doshi AB, Smith K, et al. Phenotypic diversity and correlation with the genotypes of pseudohypoaldosteronism type 1. J Pediatr Endocrinol Metab. 2019;32:959–67.
Mabillard H, Sayer JA. The molecular genetics of Gordon syndrome. Genes (Basel). 2019;10:986.
Bökenkamp A, Ludwig M. The oculocerebrorenal syndrome of Lowe: an update. Pediatr Nephrol. 2016;31:2201–12.
Watanabe T. Improving outcomes for patients with distal renal tubular acidosis: recent advances and challenges ahead. Pediatric Health Med Ther. 2018;9:181–90.
Park E, Cho MH, Hyun HS, et al. Genotype-phenotype analysis in pediatric patients with distal renal tubular acidosis. Kidney Blood Press Res. 2018;43:513–21.
Uduman J, Yee J. Pseudo-renal tubular acidosis: Conditions mimicking renal tubular acidosis. Adv Chronic Kidney Dis. 2018;25:358–65.
Kraut JA, Madias NE. Serum anion gap: its uses and limitations in clinical medicine. Clin J Am Soc Nephrol. 2007;2:162–74.
Winter SD, Pearson JR, Gabow PA, Schultz AL, Lepoff RB. The fall of the serum anion gap. Arch Intern Med. 1990;150:311–3.
Batlle D, Ba Aqeel SH, Marquez A. The urine anion gap in context. Clin J Am Soc Nephrol. 2018;13:195–7.
Batlle D, Chin-Theodorou J, Tucker BM. Metabolic acidosis or respiratory alkalosis? Evaluation of a low plasma bicarbonate using the urine anion gap. Am J Kidney Dis. 2017;70:440–4.
Palmer BF, Clegg DJ. The use of selected urine chemistries in the diagnosis of kidney disorders. Clin J Am Soc Nephrol. 2019;14:306–16.
Elkinton JR, Huth EJ, Webster GD Jr, McCance RA. The renal excretion of hydrogen ion in renal tubular acidosis. I. Quantitative assessment of the response to ammonium chloride as an acid load. Am J Med. 1960;29:554–75.
Batlle D, Grupp M, Gaviria M, Kurtzman NA. Distal renal tubular acidosis with intact capacity to lower urinary pH. Am J Med. 1982;72:751–8.
Batlle DC. Segmental characterization of defects in collecting tubule acidification. Kidney Int. 1986;30:546–54.
Walton RJ, Bijvoet OL. Nomogram for derivation of renal threshold phosphate concentration. Lancet. 1975;2:309–10.
Imel EA, Econs MJ. Approach to the hypophosphatemic patient. J Clin Endocrinol Metab. 2012;97:696–706.
Choi MJ, Ziyadeh FN. The utility of the transtubular potassium gradient in the evaluation of hyperkalemia. J Am Soc Nephrol. 2008;19:424–6.
Walsh SB, Shirley DG, Wrong OM, Unwin RJ. Urinary acidification assessed by simultaneous furosemide and fludrocortisone treatment: an alternative to ammonium chloride. Kidney Int. 2007;71:1310–6.
Shavit L, Chen L, Ahmed F, et al. Selective screening for distal renal tubular acidosis in recurrent kidney stone formers: initial experience and comparison of the simultaneous furosemide and fludrocortisone test with the short ammonium chloride test. Nephrol Dial Transplant. 2016;31:1870–6.
Palazzo V, Provenzano A, Becherucci F, et al. The genetic and clinical spectrum of a large cohort of patients with distal renal tubular acidosis. Kidney Int. 2017;91:1243–55.
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
Conflict of Interest
None.
Additional information
Publisher’s Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
About this article
Cite this article
Bagga, A., Sinha, A. Renal Tubular Acidosis. Indian J Pediatr 87, 733–744 (2020). https://doi.org/10.1007/s12098-020-03318-8
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12098-020-03318-8