Chap52N Evaluation of stone formation

  1. Basic laboratory analysis for renal stones? [EAU]
    • Dipstick test of spot urine sample
    • • red cells;
    • • white cells;
    • • nitrite;
    • • approximate urine pH;
    • • urine microscopy and/or culture.

    • Blood
    • Serum blood sample
    • • creatinine;
    • • uric acid;
    • • (ionised) calcium;
    • • blood cell count;
  2. Abbreviated Evaluation of Single-Stone
    • History
    • Underlying predisposing conditions
    • Medications (calcium, vitamin C, vitamin D, acetazolamide, steroids)
    • Dietary excesses, inadequate fluid intake, excessive fluid loss

    • Multichannel blood screen
    • Basic metabolic panel (sodium, potassium, chloride, carbon dioxide, blood urea nitrogen, creatinine)
    • Calcium
    • Intact parathyroid hormone
    • Uric acid

    • Urine
    • Urinalysis
    • pH > 7.5: infection lithiasis
    • pH < 5.5: uric acid lithiasis
    • Sediment for crystalluria
    • Urine culture - Urea-splitting organisms: suggestive of infection lithiasis
    • Qualitative cystine

    • Radiography
    • Radiopaque stones: calcium oxalate, calcium phosphate, magnesium ammonium phosphate (struvite), cystine.
    • Radiolucent stones: uric acid, xanthine, triamterene
    • Intravenous pyelogram: radiolucent stones, anatomic abnormalities

    Stone analysis
  3. Abbreviated Protocol for low risk single stone formers?
    • • A complete medical history should be obtained from all stone formers.
    • • Patients should be screened for medical diseases that predisposeto calculi.
    • • Serum metabolic panel and urinalysis tests should beperformed.
    • • Urine microscopy for crystals may provide clues todiagnosis.
    • • Stone analysis may improve the accuracy of furtherevaluation.
    • • Basic radiography (plain films) should screen for existingcalculi.
  4. Extensive diagnostic evaluation?
    • • A complete metabolic evaluation may be obtained as anoutpatient.
    • • Calcium fast and load tests can discriminate between thevarious forms of hypercalciuria.
    • • Routine performance of calcium fast and load tests is notrequired to complete a metabolic evaluation
  5. Use of stone analysis to determine metabolic abnormalities?
    • • Stone analysis may obviate the need for a complete metabolic evaluation.
    • • Stone composition can direct metabolic investigation
  6. Metabolic evaluation of stone formation? *
    • ABG, Serum uric acid, S. calcium, PTH
    • 24 hour - urine calcium, oxalate, uric acid, citrate, Na/K+
    • Urine pH
  7. Recommendations related to stone analysis? [EAU]
    Perform stone analysis in first-time stone formers using a validated procedure (X-ray diffraction or infrared spectroscopy).

    • Repeat stone analysis in patients:
    • • presenting with recurrent stones despite drug therapy;
    • • with early recurrence after complete stone clearance;
    • • with late recurrence after a long stone-free period because stone composition may change.
  8. Most common non-metabolic disorders facilitating stone formation in children?
    • Vesicoureteral reflux
    • UPJ obstruction
    • Neurogenic bladder
    • Other voiding difficulties.
  9. Pain management in renal colic? [EAU]
    Non-steroidal anti-inflammatory as the first drug of choice. e.g. metamizol (dipyrone); alternatively, paracetamol or, depending on cardio-vascular risk factors, diclofenac*, indomethacin or ibuprofen.

    Offer renal decompression or ureteroscopic stone removal in case of analgesic refractory colic pain.
  10. Management of sepsis and anuria in the obstructed kidney? [EAU]
    Urgently decompress the collecting system in case of sepsis with obstructing stones, using percutaneous drainage or ureteral stenting.

    Delay definitive treatment of the stone until sepsis is resolved.
  11. Indication of MET therapy? [EAU]
    For (distal) ureteral stones > 5 mm.
Card Set
Chap52N Evaluation of stone formation
Metabolic evaluation