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Calcium NephrolithiasisAka: Calcium Oxalate Stone, Calcium Phosphate Stone, Calcium Oxalate Calculi, Calcium Phosphate Calculi

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  1. See Also
    1. Nephrolithiasis
    2. Nephrolithiasis Risk Factors
  2. Epidemiology
    1. Represents 75-90% of Nephrolithiasis
  3. Evaluation: General
    1. Do not perform evaluation during hospitalization
    2. Single Stone episodes with no residual stones
      1. Serum Calcium
      2. Consider 24 hour urine
        1. Urine volume
        2. Urine Calcium
    3. Recurrent, Residual or Family History of stones
      1. Urine Volume
      2. Conside Creatinine Clearance
      3. Urine Calcium (Hypercalciuria >300 mg/day)
      4. Urine Sodium
      5. Urine Uric Acid (Hyperuricosuria >750 mg/day)
      6. Urine Oxalate (Hyperoxaluria >40 mg/day)
      7. Urine Citrate (Hypocitraturia <320 mg/day)
  4. Evaluation: Stone Type
    1. Mixed Calcium Oxalate and Phosphate (See above)
      1. Hypercalciuria (50%)
      2. Low urine volume (30-50%)
      3. Hyperoxaluria (20-30%)
      4. Hypocitraturia (20-30%)
      5. Hyperuricosuria (20%)
    2. Pure Calcium Phosphate Stones (uncommon)
      1. Causes
        1. Distal Renal Tubular Acidosis
        2. Primary Hyperparathyroidism
        3. Excessive alkalinization
        4. Sarcoidosis
      2. Obtain Serum Electrolytes
        1. Hyperkalemia
        2. Serum Bicarbonate increased
        3. Hyperchloremia
  5. Evaluation: Specific Populations
    1. Hmong patients more commonly have increased Uric Acid
    2. African americans rarely form calcium stones
      1. Evaluate if Hypercalciuria and Hypercalcemia
      2. Underlying causes
        1. Sarcoidosis
        2. Primary Hyperparathyroidism
  6. Management
    1. See Nephrolithiasis
    2. Increase fluid increase >2.5 Liters per day
    3. Hypercalcemia
      1. Evaluate for Hyperparathyroidism
    4. Normocalcemia and uncomplicated calcium stone disease
      1. Normocalciuria
        1. Potassium Citrate (Urocit-K) 20 meq PO tid
      2. Hypercalciuria (>250 mg/day)
        1. Increase Dietary Calcium >1000 mg/day
          1. Take calcium only with meals
          2. Take calcium as food not calcium supplement
        2. Follow low sodium diet (<150 meq/day)
        3. Decrease dietary meat intake
        4. Avoid Loop Diuretics (e.g. Lasix)
        5. Medications: Thiazide Diuretic with potassium
          1. Hydrochlorothiazide 25 to 50 mg PO daily and
          2. Potassium supplement
            1. Normocitraturia:
              1. Potassium chloride
            2. Hypocitraturia:
              1. Potassium citrate 20 meq PO tid
    5. Hyperoxaluria
      1. Mild Hyperoxalauria (40-60 mg/day)
        1. Normal Dietary Calcium
        2. Low Oxalate Diet
        3. Decrease Ascorbic acid <1-2 grams/day
      2. Enteric Hyperoxaluria (60-80 mg/day)
        1. Calcium Supplements with meals
        2. Low Fat Diet
        3. Trial of Cholestyramine 2-4 grams per meal
      3. Primary Hyperoxaluria (>80 mg/day)
        1. Trial Pyridoxine (Vitamin B6)
        2. Monitor Renal Function frequently
        3. Referral to Hepatology
  7. Prognosis
    1. Recurrence risk within 2 years: 35%

Calcium nephrolithiasis (C1855801)

ConceptsFinding (T033)
EnglishCalcium nephrolithiasis
SourcesOMIM
Derived from the NIH UMLS (Unified Medical Language System)



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