II. Risk Factors: General

  1. Increases with advancing age up to 65 years
  2. Male gender (men account for 66% of cases)
  3. Geographic location (hot, arid climates)
    1. Southeastern United States ("stone belt")
    2. Mediterranean countries
    3. Middle Eastern countries
    4. Northern Australia

III. Risk Factors: Anatomic Abnormalities

  1. Horseshoe Kidney
  2. Medullary Sponge Kidney
  3. Ureteral Stricture
  4. Ureterocele
  5. Vesicoureteral reflux
  6. Ureteropelvic junction obstruction

IV. Risk Factors: Inherited Conditions

  1. Polycystic Kidney Disease
  2. Renal Tubular Acidosis Type I
  3. Cystinuria
  4. Hypocitraturia
  5. Hypercalciuria
  6. Prmary hyperoxaluria
  7. Lesch-Nyhan Syndrome
  8. 2,8-dihydroxyadenine
  9. Cystic Fibrosis
  10. Xanthinuria

V. Risk Factors: Gastrointestinal Disorders

  1. Inflammatory Bowel Disease (Crohns Disease, Ulcerative Colitis)
    1. Higher risk of Calcium Oxalate Stones
  2. Urinary diversion (enteric hyperoxaluria)
  3. Intestinal resection
  4. Jejunoileal Bypass (Bariatric Surgery)
  5. Intestinal malabsorption

VI. Risk Factors: Miscellaneous

VII. Risk Factors: Medications

VIII. Risk Factors: Dietary and Hydration Factors

  1. Low Urine Volume
    1. Inadequate access to hydration or restrooms
    2. Athlete
    3. Heat exposure
    4. Bowel Disease
      1. Bowel Surgery (e.g. Ileostomy)
      2. Infammatory bowel disease (e.g. Crohn's Disease)
      3. Chronic Diarrhea
      4. Peptic Ulcer Disease
  2. Other dietary factors
    1. Animal Protein intake (see aciduria below)
      1. Purine Containing Foods and other Protein intake
    2. High Oxalate Containing Foods (hyperoxaluria)
    3. Excessive Sodium intake (Hypercalciuria risk)
    4. Excessive Carbohydrate intake (esp. high sugar beverages)
  3. Hypercalciuria (high Urine Calcium, 70% of stone formers)
    1. Type 1: Increased PTH (resorptive Hypercalciuria)
      1. Hyperparathyroidism
      2. Sarcoidosis
    2. Type 2: Increased Calcium absorption from gut
    3. Type 3: Increased Urinary Phosphorus loss
    4. Type 4: Increased Urinary Calcium loss
  4. Hyperoxaluria (high urine oxalate)
    1. Citrate deficiency (not oxalate metabolism problem)
  5. Hypocitraturia (low urine citrate, e.g. Distal Renal Tubular Acidosis)
  6. Hyperuricosuria (high Urine Uric Acid)
  7. Alkaline urine (pH>6.5) is a risk factor for Calcium Phosphate Stones
  8. Acidosis and aciduria (results in loss of citrate, higher risk of Uric Acid stones)
    1. Acetazolamide (Diamox)
    2. Renal Tubular Acidosis
    3. Protein loading (especially with animal Protein)
    4. Bowel disease (see above)

IX. Risk Factor: Other risks for recurrent stone

  1. Early onset Urolithiasis (child or teen onset)
  2. Family History of stone formation
  3. Infection associated stones (Struvite Stones, carbonate apatite stones)
  4. Calcium Phosphate Stones
  5. Uric Acid stones

Images: Related links to external sites (from Bing)

Related Studies