Uric acid nephrolithiasis: A systemic metabolic disorder

Michael R. Wiederkehr, Orson W. Moe

Research output: Contribution to journalArticle

27 Scopus citations

Abstract

Uric acid nephrolithiasis is characteristically a manifestation of a systemic metabolic disorder. It has a prevalence of about 10% among all stone formers, the third most common type of kidney stone in the industrialized world. Uric acid stones form primarily due to an unduly acid urine; less deciding factors are hyperuricosuria and a low urine volume. The vast majority of uric acid stone formers have the metabolic syndrome, and not infrequently, clinical gout is present as well. A universal finding is a low baseline urine pH plus insufficient production of urinary ammonium buffer. Persons with gastrointestinal disorders, in particular chronic diarrhea or ostomies, and patients with malignancies with a large tumor mass and high cell turnover comprise a less common but nevertheless important subset. Pure uric acid stones are radiolucent but well visualized on renal ultrasound or computer tomography. A 24 h urine collection for stone risk analysis provides essential insight into the pathophysiology of stone formation and may guide therapy. Management includes a liberal fluid intake and dietary modification. Potassium citrate to alkalinize the urine to a goal pH between 6 and 6.5 is essential, as undissociated uric acid deprotonates into its much more soluble urate form.

Original languageEnglish (US)
Pages (from-to)207-217
Number of pages11
JournalClinical Reviews in Bone and Mineral Metabolism
Volume9
Issue number3-4
DOIs
StatePublished - Dec 1 2011

    Fingerprint

Keywords

  • Acid urine
  • Alkaline
  • Ammonium
  • Gout
  • Hyperuricosuria
  • Metabolic syndrome
  • PH
  • Potassium citrate
  • Uric acid nephrolithiasis
  • Urine buffer

ASJC Scopus subject areas

  • Endocrinology, Diabetes and Metabolism
  • Orthopedics and Sports Medicine
  • Endocrinology

Cite this