Predictive value of kidney stone composition in the detection of metabolic abnormalities

Am J Med. 2003 Jul;115(1):26-32. doi: 10.1016/s0002-9343(03)00201-8.


Purpose: To determine if kidney stone composition can predict the underlying medical diagnosis, and vice versa.

Methods: We studied 1392 patients with kidney stones who underwent a complete ambulatory evaluation and who submitted one or more stones for analysis. We ascertained the associations between medical diagnosis and stone composition.

Results: The most common kidney stones were composed of calcium oxalate (n = 1041 patients [74.8%]), mixed calcium oxalate-calcium apatite (n = 485 [34.8%]), and calcium apatite alone (n = 146 [10.5%]). The most common medical diagnoses were hypocitraturia (n = 616 patients [44.3%]), absorptive hypercalciuria (n = 511 [36.7%]), and hyperuricosuria (n = 395 [28.4%]). Calcium apatite and mixed calcium oxalate-calcium apatite stones were associated with the diagnoses of renal tubular acidosis and primary hyperparathyroidism (odds ratios >/=2), but not with chronic diarrheal syndromes. As the phosphate content of the stone increased from calcium oxalate to mixed calcium oxalate-calcium apatite, and finally to calcium apatite, the percentage of patients with renal tubular acidosis increased from 5% (57/1041) to 39% (57/146), and those with primary hyperparathyroidism increased from 2% (26/1041) to 10% (14/146). Calcium oxalate stones were associated with chronic diarrheal syndromes, but not with renal tubular acidosis. Pure and mixed uric acid stones were strongly associated with a gouty diathesis, and vice versa. Chronic diarrheal syndromes and uric acid stones were associated with one another, and brushite stones were associated with renal tubular acidosis. As expected, there was a very strong association between infection stones and infection, and between cystine stones and cystinuria.

Conclusion: Stone composition has some predictive value in diagnosing medical conditions, and vice versa, especially for noncalcareous stones.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Acidosis, Renal Tubular / epidemiology
  • Acidosis, Renal Tubular / metabolism*
  • Adolescent
  • Adult
  • Aged
  • Ambulatory Care
  • Apatites / analysis
  • Calcium / urine
  • Calcium Oxalate / analysis
  • Citrates / urine
  • Diarrhea / epidemiology
  • Female
  • Gout / epidemiology
  • Gout / metabolism*
  • Humans
  • Hyperparathyroidism / epidemiology
  • Hyperparathyroidism / metabolism*
  • Kidney Calculi / chemistry*
  • Kidney Calculi / diagnosis*
  • Kidney Calculi / epidemiology
  • Male
  • Middle Aged
  • Phosphates / analysis
  • Predictive Value of Tests
  • Spectroscopy, Fourier Transform Infrared
  • Uric Acid / urine


  • Apatites
  • Citrates
  • Phosphates
  • Calcium Oxalate
  • Uric Acid
  • Calcium