Influence of alkaline solutions on chemolitholysis and lithotripsy of uric acid stones. An in vitro study.

OBJECTIVES

This study was performed to look for an improvement of therapeutic strategies with regard to the treatment of uric acid stones using artificial stones made of uric acid (BON(N)-STONES) which are comparable to their natural counterparts.

MATERIALS AND METHODS

Using an experimental arrangement simulating the physiological conditions in the upper urinary tract the efficacy of different alkaline solutions and artificial urine in dissolving artificial uric acid stones (BON(N)-STONES) was investigated. The dissolution of natural uric acid stones was measured and investigations on shock wave lithotripsy (SWL) combined with initial chemolytic treatment of the stones were performed.

RESULTS

The efficacy of alkaline solutions, especially THAM at a pH of 10, in dissolving artificial uric acid stones was demonstrated. The investigations on SWL showed a significant improvement on stone comminution of artificial uric acid stones after initial chemolytic treatment with THAM.

CONCLUSIONS

New basics to improve dissolution of uric acid stones have been developed by performing standardized in vitro investigations. The suggestion was confirmed that stone fragility and thus SWL can be improved by varying the physical properties of uric acid stones through initial treatment with THAM solution.