New chemolysis for urological calcium phosphate calculi – a study in vitro

BACKGROUND: Advances in techniques have left very few indications for open surgical extraction of urinary stones currently. These advances notwithstanding, the search continues for medical approaches to urinary stone management. In this study, we perform an in vitro study analyzing the efficiency and prospect of two new complex solutions in urological calcium phosphate calculi dissolution. METHODS: Eighteen stones composed mainly of calcium phosphates were taken from patients who underwent kidney stone surgery. These stones were large enough (weight range 0.514–0.928 g) to be fragmented and matched equally into six groups. Chemolysis of phosphate stones was done with six different solvents and was repeated 3 times with 6 stones for each solution. At 24, 48 and 72 h, reduction in weight, percentage weight change, and dissolution rate; the dissolution rates at pH 5.0, 7.0 and 8.5 for each solution, using different cations (Na(+), K(+ )or Ca(2+)), according to different dilutions (1:1, 1:2, 1:3, 1:4) of S1 and S2 were simultaneously determined. RESULTS: Calcium phosphate calculi were poorly dissolved by Phys and Art, and they had a low dissolution rate in pH 8.5 EDTA. The most effective solutions were S1, S2 and R, with 72 h mean dissolution rates: 5.75 ± 0.44 mg/hr (S1), 5.2 ± 0.63 mg/hr (S2), 4.55 ± 0.46 mg/hr (R) ([Image: see text] ± s, p < 0.01 R, S1 and S2 vs Phys, Art and EDTA; p < 0.05, S1 vs R, LSD-test). The mean percentage weight loss at 72 h was: 52.1 ± 15.75 % (S1), 44.4 ± 7.37 % (S2) and 40.5 ± 3.67 % (R) ([Image: see text] ± s, p < 0.01 R, S1 and S2 vs Phys, Art and EDTA, LSD-test). Diluted twice, S1 and S2 had even better effectiveness than their initial solution. The additive of Na(+), K(+ )or Ca(2+ )greatly reduced the dissolution rates of S1, S2. CONCLUSION: Our data indicate that test solutions S1 and S2 are effective solvents in the chemolysis of calcium phosphate stones. At twice dilutions, these solutions are even more useful in the treatment of stone disease

Recurrence of lithiasis after extracorporeal lithotripsy, percutaneous surgery, and open surgery for calculi of the upper urinary tract

The safety and short-term effectiveness of percutaneous nephrolithotomy (PCNL) and extracorporeal shock wave lithotripsy (ESWL) have already been well established. However, long-term follow-up studies are essential to prove that the recurrence rate after PCNL and/or ESWL is equal or even better than that of surgery. We reviewed 57 patients treated with ESWL monotherapy, 45 patients treated by PCNL (or by PCNL combined with ESWL for complete staghorn stones) and 59 patients treated by open surgery who all had at least three years of follow-up. The overall recurrence rate for ESWL was 37% for PCNL and for open surgery 39%. ESWL, PCNL and open surgery all showed a higher rate of recurrence and persistent bacteriuria when associated with residual stones. Therefore every effort should be made to remove residual fragments following stone treatment. We conclude that because of its efficacy and low morbidity ESWL should be the treatment of choice for most of renal calculi. Complete staghorn calculi are best treated with open surgery because the complete elimination of all calculous material and the eradication of infection are achieved at a higher rate than by PCNL and ESWL