Management of Kidney Stones

Initial Evaluation

The American Urological Association recommends obtaining stone analysis at least once when a stone is available to guide specific preventive measures 1
The American Urological Association suggests reviewing available imaging studies to quantify stone burden and identify patients at higher risk of recurrence 1
The American Urological Association recommends performing metabolic testing with 24-hour urine collections in high-risk or interested first-time stone formers and all recurrent stone formers 1
The American Urological Association recommends analyzing 24-hour urine for total volume, pH, and other factors such as calcium, oxalate, uric acid, citrate, sodium, potassium, and creatinine 1
The American Urological Association suggests obtaining serum intact parathyroid hormone level if primary hyperparathyroidism is suspected 1

The American Urological Association recommends increasing fluid intake to achieve urine volume of at least 2.5 liters daily 2
For patients with calcium stones, the American Urological Association suggests maintaining normal dietary calcium intake of 1,000-1,200 mg per day and limiting sodium intake to 2,300 mg daily 3
The American Urological Association recommends consuming ample fruits and vegetables to counterbalance acid load for patients with calcium stones 4
For patients with cystine stones, the American Urological Association suggests targeting higher fluid intake of at least 4 liters per day to decrease urinary cystine concentration 4

For patients with calcium stones and hypercalciuria, the American Urological Association recommends thiazide diuretics and continuing dietary sodium restriction to maximize hypocalciuric effect 4
For patients with calcium stones and hypocitraturia, the American Urological Association suggests potassium citrate therapy 4
For patients with uric acid stones, the American Urological Association recommends potassium citrate to increase urinary pH to approximately 6.0 5

The American Urological Association recommends obtaining 24-hour urine specimen within six months of initiating treatment to assess response to therapy 5
The American Urological Association suggests monitoring for adverse effects in patients on pharmacological therapy, such as hypokalemia with thiazides and hyperkalemia with potassium citrate 4, 5

The American Urological Association recommends thiazides combined with potassium citrate for calcium stones with hypercalciuria, as this combination may be used when other metabolic abnormalities are absent or adequately addressed but stone formation persists 6
Potassium citrate therapy is recommended for patients with low or relatively low urinary citrate, with Grade B evidence from prospective RCTs 6
Potassium citrate is preferred over sodium citrate because sodium load increases urinary calcium excretion, according to the American Urological Association 7
Allopurinol is recommended for patients with hyperuricosuria (>800 mg/day) and normal urinary calcium, with Grade B evidence from prospective RCTs 6
The American Urological Association recommends potassium citrate as first-line therapy to raise urinary pH to approximately 6.0 for uric acid stones, as most patients have low urinary pH rather than hyperuricosuria 6
Acetohydroxamic acid (AHA) may be considered as a urease inhibitor in patients at high risk for recurrence of struvite stones or when surgery is not feasible, though extensive side effects may limit use 7
Potassium citrate therapy is recommended if hypocitraturia is present for calcium phosphate stones, as citrate is a potent inhibitor of calcium phosphate crystallization 6
Exercise caution with excessive alkalinization for calcium phosphate stones, as calcium phosphate solubility decreases at higher pH, according to the American Urological Association 7