Uric acid nephrolithiasis

Uric acid or urine pH?

Research output: Chapter in Book/Report/Conference proceedingChapter

Abstract

The prevalence of uric acid nephrolithiasis in the general US population is approximately 8∈%. However, the prevalence of uric acid stones among diabetic and obese populations has been reported to be significantly high, approaching 3.5-fold greater than the general population. Although three main etiologic factors, including low urine volume, hyperuricosuria, and unduly urine acidity, have been implicated in the pathogenesis of uric acid nephrolithiasis, abnormal urine pH has been shown to play a key pathogenic role in uric acid precipitation and uric acid stone formation. Uric acid is a weak organic acid with an ionization constant (pKa∈=∈5.5); hence, at a urinary pH∈≤∈5.5 the urinary environment becomes supersaturated with highly insoluble undissociated uric acid, which greatly imposes the risk of uric acid development and precipitation. Under normal circumstances, uric acid solubility is limited to 96 mg/L; thus, humans with urinary uric acid excretion of approximately 600-800 mg/day must be at risk for uric acid precipitation. However, urinary pH plays a dominate role in keeping uric acid in the solution. Careful studies have demonstrated that at urinary pH between 6.2 and 6.4, the urinary environment becomes undersaturated with respect to undissociated uric acid content. Such an environment has been shown to be associated with a significantly reduced risk of uric acid stone formation. Given this predominate role of urinary pH, urinary uric acid must exceed 1,100 mg/day in order to promote uric acid precipitation. This condition rarely occurs in the majority of patients with idiopathic nephrolithiasis in whom urinary acid excretion was reported to be normal. Uric acid-lowering drugs must only be tried in some patients with primary gout, with genetic abnormalities in uric acid pathways including inborn errors in metabolism, uric acid metabolism, and those with accelerated tissue turnover.

Original languageEnglish (US)
Title of host publicationPractical Controversies in Medical Management of Stone Disease
PublisherSpringer New York
Pages91-103
Number of pages13
Volume9781461495758
ISBN (Print)9781461495758, 1461495741, 9781461495741
DOIs
StatePublished - Nov 1 2013

Fingerprint

Nephrolithiasis
Uric Acid
Urine
Population
Inborn Errors Metabolism

Keywords

  • Metabolic syndrome
  • Nephrolithiasis
  • Uric acid
  • Urine pH

ASJC Scopus subject areas

  • Medicine(all)

Cite this

Sakhaee, K. (2013). Uric acid nephrolithiasis: Uric acid or urine pH? In Practical Controversies in Medical Management of Stone Disease (Vol. 9781461495758, pp. 91-103). Springer New York. https://doi.org/10.1007/978-1-4614-9575-8_7

Uric acid nephrolithiasis : Uric acid or urine pH? / Sakhaee, Khashayar.

Practical Controversies in Medical Management of Stone Disease. Vol. 9781461495758 Springer New York, 2013. p. 91-103.

Research output: Chapter in Book/Report/Conference proceedingChapter

Sakhaee, K 2013, Uric acid nephrolithiasis: Uric acid or urine pH? in Practical Controversies in Medical Management of Stone Disease. vol. 9781461495758, Springer New York, pp. 91-103. https://doi.org/10.1007/978-1-4614-9575-8_7
Sakhaee K. Uric acid nephrolithiasis: Uric acid or urine pH? In Practical Controversies in Medical Management of Stone Disease. Vol. 9781461495758. Springer New York. 2013. p. 91-103 https://doi.org/10.1007/978-1-4614-9575-8_7
Sakhaee, Khashayar. / Uric acid nephrolithiasis : Uric acid or urine pH?. Practical Controversies in Medical Management of Stone Disease. Vol. 9781461495758 Springer New York, 2013. pp. 91-103
@inbook{7ff3ac7ecccc4c09879395beea1fe313,
title = "Uric acid nephrolithiasis: Uric acid or urine pH?",
abstract = "The prevalence of uric acid nephrolithiasis in the general US population is approximately 8∈{\%}. However, the prevalence of uric acid stones among diabetic and obese populations has been reported to be significantly high, approaching 3.5-fold greater than the general population. Although three main etiologic factors, including low urine volume, hyperuricosuria, and unduly urine acidity, have been implicated in the pathogenesis of uric acid nephrolithiasis, abnormal urine pH has been shown to play a key pathogenic role in uric acid precipitation and uric acid stone formation. Uric acid is a weak organic acid with an ionization constant (pKa∈=∈5.5); hence, at a urinary pH∈≤∈5.5 the urinary environment becomes supersaturated with highly insoluble undissociated uric acid, which greatly imposes the risk of uric acid development and precipitation. Under normal circumstances, uric acid solubility is limited to 96 mg/L; thus, humans with urinary uric acid excretion of approximately 600-800 mg/day must be at risk for uric acid precipitation. However, urinary pH plays a dominate role in keeping uric acid in the solution. Careful studies have demonstrated that at urinary pH between 6.2 and 6.4, the urinary environment becomes undersaturated with respect to undissociated uric acid content. Such an environment has been shown to be associated with a significantly reduced risk of uric acid stone formation. Given this predominate role of urinary pH, urinary uric acid must exceed 1,100 mg/day in order to promote uric acid precipitation. This condition rarely occurs in the majority of patients with idiopathic nephrolithiasis in whom urinary acid excretion was reported to be normal. Uric acid-lowering drugs must only be tried in some patients with primary gout, with genetic abnormalities in uric acid pathways including inborn errors in metabolism, uric acid metabolism, and those with accelerated tissue turnover.",
keywords = "Metabolic syndrome, Nephrolithiasis, Uric acid, Urine pH",
author = "Khashayar Sakhaee",
year = "2013",
month = "11",
day = "1",
doi = "10.1007/978-1-4614-9575-8_7",
language = "English (US)",
isbn = "9781461495758",
volume = "9781461495758",
pages = "91--103",
booktitle = "Practical Controversies in Medical Management of Stone Disease",
publisher = "Springer New York",

}

TY - CHAP

T1 - Uric acid nephrolithiasis

T2 - Uric acid or urine pH?

AU - Sakhaee, Khashayar

PY - 2013/11/1

Y1 - 2013/11/1

N2 - The prevalence of uric acid nephrolithiasis in the general US population is approximately 8∈%. However, the prevalence of uric acid stones among diabetic and obese populations has been reported to be significantly high, approaching 3.5-fold greater than the general population. Although three main etiologic factors, including low urine volume, hyperuricosuria, and unduly urine acidity, have been implicated in the pathogenesis of uric acid nephrolithiasis, abnormal urine pH has been shown to play a key pathogenic role in uric acid precipitation and uric acid stone formation. Uric acid is a weak organic acid with an ionization constant (pKa∈=∈5.5); hence, at a urinary pH∈≤∈5.5 the urinary environment becomes supersaturated with highly insoluble undissociated uric acid, which greatly imposes the risk of uric acid development and precipitation. Under normal circumstances, uric acid solubility is limited to 96 mg/L; thus, humans with urinary uric acid excretion of approximately 600-800 mg/day must be at risk for uric acid precipitation. However, urinary pH plays a dominate role in keeping uric acid in the solution. Careful studies have demonstrated that at urinary pH between 6.2 and 6.4, the urinary environment becomes undersaturated with respect to undissociated uric acid content. Such an environment has been shown to be associated with a significantly reduced risk of uric acid stone formation. Given this predominate role of urinary pH, urinary uric acid must exceed 1,100 mg/day in order to promote uric acid precipitation. This condition rarely occurs in the majority of patients with idiopathic nephrolithiasis in whom urinary acid excretion was reported to be normal. Uric acid-lowering drugs must only be tried in some patients with primary gout, with genetic abnormalities in uric acid pathways including inborn errors in metabolism, uric acid metabolism, and those with accelerated tissue turnover.

AB - The prevalence of uric acid nephrolithiasis in the general US population is approximately 8∈%. However, the prevalence of uric acid stones among diabetic and obese populations has been reported to be significantly high, approaching 3.5-fold greater than the general population. Although three main etiologic factors, including low urine volume, hyperuricosuria, and unduly urine acidity, have been implicated in the pathogenesis of uric acid nephrolithiasis, abnormal urine pH has been shown to play a key pathogenic role in uric acid precipitation and uric acid stone formation. Uric acid is a weak organic acid with an ionization constant (pKa∈=∈5.5); hence, at a urinary pH∈≤∈5.5 the urinary environment becomes supersaturated with highly insoluble undissociated uric acid, which greatly imposes the risk of uric acid development and precipitation. Under normal circumstances, uric acid solubility is limited to 96 mg/L; thus, humans with urinary uric acid excretion of approximately 600-800 mg/day must be at risk for uric acid precipitation. However, urinary pH plays a dominate role in keeping uric acid in the solution. Careful studies have demonstrated that at urinary pH between 6.2 and 6.4, the urinary environment becomes undersaturated with respect to undissociated uric acid content. Such an environment has been shown to be associated with a significantly reduced risk of uric acid stone formation. Given this predominate role of urinary pH, urinary uric acid must exceed 1,100 mg/day in order to promote uric acid precipitation. This condition rarely occurs in the majority of patients with idiopathic nephrolithiasis in whom urinary acid excretion was reported to be normal. Uric acid-lowering drugs must only be tried in some patients with primary gout, with genetic abnormalities in uric acid pathways including inborn errors in metabolism, uric acid metabolism, and those with accelerated tissue turnover.

KW - Metabolic syndrome

KW - Nephrolithiasis

KW - Uric acid

KW - Urine pH

UR - http://www.scopus.com/inward/record.url?scp=84930030990&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84930030990&partnerID=8YFLogxK

U2 - 10.1007/978-1-4614-9575-8_7

DO - 10.1007/978-1-4614-9575-8_7

M3 - Chapter

SN - 9781461495758

SN - 1461495741

SN - 9781461495741

VL - 9781461495758

SP - 91

EP - 103

BT - Practical Controversies in Medical Management of Stone Disease

PB - Springer New York

ER -